1999 Blazer ignition problem
skyzend
07-24-2009, 08:31 AM
I've recently had trouble starting my blazer intermittantly
Seems like if the weather is damp or rainy it won't start.
I do not even get a misfire when attempting to start
I've checked the fuel pressure and I have aprox 58 psi prior to turning the key.
I did get going during damp weather ... must have been a fluke ... lol
I noticed that I had a nice spark dancing between the ignition coil wire boot at the base and the ignition coil heavy metal "magnet" piece that runs through the center of the coil.
Aha ... that would definately cause starting failure if things are damp :)
I've replaced the spark plug wires, Distributor cap and rotor (general maintenance, need to be done anyway).
And the sparking still happens.
I replaced the ignition coil and the spark is still there ... although not as pronounced.
I've done my best to ensure that the coil connection wire boot is fully seated ... and still I get a spark that comes from the bottom of the boot to the coil magnet. It jumps about 3/8 inch.
Any suggestions on how I can stop this from happening?
Has anyone seen this sort of thing before?
Seems like if the weather is damp or rainy it won't start.
I do not even get a misfire when attempting to start
I've checked the fuel pressure and I have aprox 58 psi prior to turning the key.
I did get going during damp weather ... must have been a fluke ... lol
I noticed that I had a nice spark dancing between the ignition coil wire boot at the base and the ignition coil heavy metal "magnet" piece that runs through the center of the coil.
Aha ... that would definately cause starting failure if things are damp :)
I've replaced the spark plug wires, Distributor cap and rotor (general maintenance, need to be done anyway).
And the sparking still happens.
I replaced the ignition coil and the spark is still there ... although not as pronounced.
I've done my best to ensure that the coil connection wire boot is fully seated ... and still I get a spark that comes from the bottom of the boot to the coil magnet. It jumps about 3/8 inch.
Any suggestions on how I can stop this from happening?
Has anyone seen this sort of thing before?
old_master
07-24-2009, 03:03 PM
Factory spec for fuel pressure is 60psi to 66psi, key on, engine off, fuel pump running. At 58psi the fuel mixture is lean and could cause a secondary ignition voltage spike like you're experiencing.
As far as tune up parts, AC Delco 41-932 plugs, D328A distributor cap, D465 rotor, AC Delco 9746KK or Autolite 96871 Pro Series wires. These are the best parts you can get, (at any price), and will give the best performance. Anything else, and you're bound to experience trouble. Make sure you use silicone dielectric on all terminals, both inside and out, of the cap, and at the spark plugs.
As far as tune up parts, AC Delco 41-932 plugs, D328A distributor cap, D465 rotor, AC Delco 9746KK or Autolite 96871 Pro Series wires. These are the best parts you can get, (at any price), and will give the best performance. Anything else, and you're bound to experience trouble. Make sure you use silicone dielectric on all terminals, both inside and out, of the cap, and at the spark plugs.
skyzend
07-24-2009, 08:02 PM
OK, now you've sparked my curiosity.
How can lean fuel mixture possibly generate any extra secondary electrical charge that shows up at the coil. This seems to defy principles of physics.
I am an Electrical Engineer with 25 years of experience and would keenly like for someone to explain how this could happen.
Now if you told me that an incorrect sparkplug connection, bad wire or spark plug would hinder the charge from finding its way back to ground through the sparkplug. and that the charge would try to find the easiest path which might be via the coil wire boot, I would accept this as a plausible explanation ... and I would go back and check connections, look for a misfire, bad plug etc. I need to do some work here ... As this IS a plausible explanation ... glad I thought of it :)
Your comment on the silicone dielectric is likely a good suggestion. Not just likely ... it is a good suggestion. I'll try this as it will likely help to interupt the arc path I see during damp weather.
As for the comment about the parts...
I have already stated that I have already made the upgrades to distributor and wiring. Nothing more to do here.
The parts you list are for higher end replacements and are quite exceptional in performance. I do find it irresponsible to state that anything less is inadequate. There are many makes and manufacturers that make quality parts at a reasonable price.
I have been using run of the mill (not high end) parts for 10 years and have only experienced normal wear and tear, and never the trouble you almost guarantee. Even cheap parts like crappy brake pads work well over their much limited lifespan. They don't give you trouble ... install exactly the same as the expensive ones, and are equally as effective, and they have the same symptoms when they wear out. My blazer is now 360,000 kms and usually runs as though it is just broken in. I'm sure it will again.
The only exception to my comment is front wheel hub assembly.
Dealer parts suck and so do any other replacement I have tried.
GM engineers failed terribly when designing this part for durability.
Manufacturers share an equal responsibility for designing in the early obsolesence that enforce frequent expense of early replacement.
I'm glad they don't design artificial hips.
How can lean fuel mixture possibly generate any extra secondary electrical charge that shows up at the coil. This seems to defy principles of physics.
I am an Electrical Engineer with 25 years of experience and would keenly like for someone to explain how this could happen.
Now if you told me that an incorrect sparkplug connection, bad wire or spark plug would hinder the charge from finding its way back to ground through the sparkplug. and that the charge would try to find the easiest path which might be via the coil wire boot, I would accept this as a plausible explanation ... and I would go back and check connections, look for a misfire, bad plug etc. I need to do some work here ... As this IS a plausible explanation ... glad I thought of it :)
Your comment on the silicone dielectric is likely a good suggestion. Not just likely ... it is a good suggestion. I'll try this as it will likely help to interupt the arc path I see during damp weather.
As for the comment about the parts...
I have already stated that I have already made the upgrades to distributor and wiring. Nothing more to do here.
The parts you list are for higher end replacements and are quite exceptional in performance. I do find it irresponsible to state that anything less is inadequate. There are many makes and manufacturers that make quality parts at a reasonable price.
I have been using run of the mill (not high end) parts for 10 years and have only experienced normal wear and tear, and never the trouble you almost guarantee. Even cheap parts like crappy brake pads work well over their much limited lifespan. They don't give you trouble ... install exactly the same as the expensive ones, and are equally as effective, and they have the same symptoms when they wear out. My blazer is now 360,000 kms and usually runs as though it is just broken in. I'm sure it will again.
The only exception to my comment is front wheel hub assembly.
Dealer parts suck and so do any other replacement I have tried.
GM engineers failed terribly when designing this part for durability.
Manufacturers share an equal responsibility for designing in the early obsolesence that enforce frequent expense of early replacement.
I'm glad they don't design artificial hips.
old_master
07-24-2009, 10:36 PM
There is a wealth of information here on AF. There are several experienced and knowledgable members that have been certified master technicians diagnosing and repairing vehicles for well over 30 years, myself included. With experience, a technician learns what brand of parts work, and what brand doesn't, in each situation. Other members come here looking to tap into that experience and information. Some are looking for technical information, and others for step by step instructions on how to diagnose a problem or the proper procedure to replace a part. It's up to each member to decide whether to use the information or not. If he has questions, most of us here are glad to explain.
I can tell you from experience that a lean fuel mixture requires more voltage to ignite than a rich mixture. It's very obvious when the engine is on an ocilloscope, it sticks out like a sore thumb. Pretty simple scenario: little fuel needs big spark, lotta fuel, little spark. Manufacturers specify a certain gap for the spark plugs to give the correct spark. The injector and popet system used on your engine will cause a lean mixture if the fuel pressure is below 60psi. Same thing goes for a clogged injector...lean mixture and a misfire.
I totally agree that high secondary resistance, (plugs, wires, cap, rotor and coil) absolutely will cause an increase in coil output, and can also cause a misfire.
In response to your comment about parts: "I do find it irresponsible to state that anything less is inadequate." If the engine does not perform properly with a certain brand of part, most people would agree that the part is inadequate. If you look around the forum, you'll find countless times where certain brands of parts are totally inadequate. Bosch spark plugs and fuel pumps are great, but not on a GM 4.3L, you'll have problems... guaranteed. Bosch oxygen sensors, on the other hand, are one of the best you can buy. As you mentioned, OEM hub assemblies are inferior, you learned that from experience. Timken and BCA National are a far better choice for quality.
If a member recommends a certain brand of part, it's from experience, and he's trying to save you a headache and save you some money. Hope this helps.
I can tell you from experience that a lean fuel mixture requires more voltage to ignite than a rich mixture. It's very obvious when the engine is on an ocilloscope, it sticks out like a sore thumb. Pretty simple scenario: little fuel needs big spark, lotta fuel, little spark. Manufacturers specify a certain gap for the spark plugs to give the correct spark. The injector and popet system used on your engine will cause a lean mixture if the fuel pressure is below 60psi. Same thing goes for a clogged injector...lean mixture and a misfire.
I totally agree that high secondary resistance, (plugs, wires, cap, rotor and coil) absolutely will cause an increase in coil output, and can also cause a misfire.
In response to your comment about parts: "I do find it irresponsible to state that anything less is inadequate." If the engine does not perform properly with a certain brand of part, most people would agree that the part is inadequate. If you look around the forum, you'll find countless times where certain brands of parts are totally inadequate. Bosch spark plugs and fuel pumps are great, but not on a GM 4.3L, you'll have problems... guaranteed. Bosch oxygen sensors, on the other hand, are one of the best you can buy. As you mentioned, OEM hub assemblies are inferior, you learned that from experience. Timken and BCA National are a far better choice for quality.
If a member recommends a certain brand of part, it's from experience, and he's trying to save you a headache and save you some money. Hope this helps.
blazee
07-25-2009, 03:55 AM
I know that it may seem like a purist approach, but I can confirm what Old Master has said in regards to the quality of parts. The Vortec engines are temperamental, and using certain parts insure their reliability. As Old Master mentioned Bosch for example, make great plugs, but they can't be used in a Vortec as they are prone to fouling. Many other spark plugs cause problems as well. I've used Autolite Platinum plugs before with no problems and other times they've caused hesitation, rough idle and lower fuel economy. Aftermarket distributor caps are one of the most common problem causers after a tune up, they simply don't have the same tolerances as the AC Delco caps, causing poor spark transfer which affects performance, and many don't seat as they should allowing moisture to enter the cap causing issues in damp and rainy conditions. For the rotors, I haven't personally seen anyone have trouble with the aftermarket ones, however considering the quality of the caps, I also use AC Delco rotors as well, because the price isn't much different. The wires.... AC Delco makes great wires, however the price is way too high, considering that you can get a set of Autolites with similar performance for 1/3 - 1/4 of the price. For the price, Autolite wires are the best value. You get an excellent electrical connection, more than adequate insulation, and boots that will seal and last a long time. Many of the other aftermarket ones simply don't perform the way they should, and the new cheapies may actually be worse than the ones you are taking off.
Note: The above was in reference to the parts for the vehicles in general, and not a diagnosis of your problem (other than checking the fitment of your cap) or a recommendation to change any parts considering I have no idea what parts/brands that you bought.
As for the spark jumping, any cracks in the boot or the coil will allow the spark to jump. Other than faulty equipment, the connection is the next suspect. Not only do you have to make sure that boot fits snugly all the way down, but also that the terminal snaps into place. As Old Master stated dielectric grease should be applied to all connections before making them.
I can't confirm that lean fuel conditions will cause a spike in the voltage of the secondary ignition system though, I haven't heard of it..... also, like you, I have an electrical engineering background and don't understand it, either. I have seen Old Master's contributions to this forum for the last few years, though, and know that he isn't the type to make stuff up.
Note: The above was in reference to the parts for the vehicles in general, and not a diagnosis of your problem (other than checking the fitment of your cap) or a recommendation to change any parts considering I have no idea what parts/brands that you bought.
As for the spark jumping, any cracks in the boot or the coil will allow the spark to jump. Other than faulty equipment, the connection is the next suspect. Not only do you have to make sure that boot fits snugly all the way down, but also that the terminal snaps into place. As Old Master stated dielectric grease should be applied to all connections before making them.
I can't confirm that lean fuel conditions will cause a spike in the voltage of the secondary ignition system though, I haven't heard of it..... also, like you, I have an electrical engineering background and don't understand it, either. I have seen Old Master's contributions to this forum for the last few years, though, and know that he isn't the type to make stuff up.
skyzend
07-25-2009, 11:51 AM
To old_master.
I can appreciate that you have 30 years of experience, but you need to change your approach. Telling me to use certain parts or I will undoubtably have problems. This whole discussion may have been avoided if you had phrased the comment as a suggestion rather than a statement of fact. I re-emphasize that I have used many different non high end parts and when properly installed have served me well.
Your comment on the amount of voltage to ignite a fuel mixture is totally bogus ... you need to go back to school. The ability for fuel to ignite whether lean or rich is strictly related to the quality of the spark. A crappy spark plug will not ignite either with any voltage large or small as well as a good plug with just enough voltage to get a clean spark. More voltage is an overcompensation that may be required to overcome poor wiring or connection before the current makes its way to the plug. If your coil is functioning properly and you have functional wires and distributor to ignite any fuel mixture that an injector can provide (if the injector is clean and functional) ... remember that if minimum fuel pressure requirements are not met then the injecctor will not fire and all bets are off. Of course my comments are made for a domestic engine and not one with performance compression RPM and cam configurations.
Also, I have checked the plugs and I am not running with a lean fuel mixture ... plugs don't lie ... my fuel mixture is good, the fuel pressure and injectors are regularly cleaned and have run fine for a long time and they continue to do so.
To Blazee,
Thank you ... your comments come across as more of a suggestion with options. I can appreciate your support for old_master, but I'm sorry, I like to tell it like it is and to start jumping to a cause right away (lean fuel), tell me a totally false secondary charge that shows up at the coil story and finally tell me I will absolutely have trouble without certain parts when its not true sounds irresponsible when coming from a seasoned technician.
Your comment about certain parts fouling up prematurely, I can see this but more often than not a good technician will look further to the root cause rather than just replacing with a more fault tolerant part.
My experience has shown that other demons are usually at work in cases like this.
To both of you and anyone else interested.
I took my own advice and investigated the possibility of high voltage not reaching a spark plug thus causing the high voltage to find an alternate route to ground (from under the coil boot). Success, The spark plug boot that is deep behind the steering column was not properly seated ... difficult to get a hand in there ... even when trying from underneith or going through the driver side wheel area. Reseated and now all is well. I did not use the silicone dielectric grease but I should have and will get some and redo the connections. Thankyou this is a really good suggestion as it will also protect from moisture getting in as well.
Another issue cleared up ...
Prior to correcting the original spark issue I had a major hesitation when accellerating. I atributed this to the ignition problem but the symptoms were exactly like a transmission starting to wear out and having the start of early slipage when starting until things warmed up. Surprizingly the hesitation is gone (I expected this) but the slippage is also gone as well. I did not expect this.
I can appreciate that you have 30 years of experience, but you need to change your approach. Telling me to use certain parts or I will undoubtably have problems. This whole discussion may have been avoided if you had phrased the comment as a suggestion rather than a statement of fact. I re-emphasize that I have used many different non high end parts and when properly installed have served me well.
Your comment on the amount of voltage to ignite a fuel mixture is totally bogus ... you need to go back to school. The ability for fuel to ignite whether lean or rich is strictly related to the quality of the spark. A crappy spark plug will not ignite either with any voltage large or small as well as a good plug with just enough voltage to get a clean spark. More voltage is an overcompensation that may be required to overcome poor wiring or connection before the current makes its way to the plug. If your coil is functioning properly and you have functional wires and distributor to ignite any fuel mixture that an injector can provide (if the injector is clean and functional) ... remember that if minimum fuel pressure requirements are not met then the injecctor will not fire and all bets are off. Of course my comments are made for a domestic engine and not one with performance compression RPM and cam configurations.
Also, I have checked the plugs and I am not running with a lean fuel mixture ... plugs don't lie ... my fuel mixture is good, the fuel pressure and injectors are regularly cleaned and have run fine for a long time and they continue to do so.
To Blazee,
Thank you ... your comments come across as more of a suggestion with options. I can appreciate your support for old_master, but I'm sorry, I like to tell it like it is and to start jumping to a cause right away (lean fuel), tell me a totally false secondary charge that shows up at the coil story and finally tell me I will absolutely have trouble without certain parts when its not true sounds irresponsible when coming from a seasoned technician.
Your comment about certain parts fouling up prematurely, I can see this but more often than not a good technician will look further to the root cause rather than just replacing with a more fault tolerant part.
My experience has shown that other demons are usually at work in cases like this.
To both of you and anyone else interested.
I took my own advice and investigated the possibility of high voltage not reaching a spark plug thus causing the high voltage to find an alternate route to ground (from under the coil boot). Success, The spark plug boot that is deep behind the steering column was not properly seated ... difficult to get a hand in there ... even when trying from underneith or going through the driver side wheel area. Reseated and now all is well. I did not use the silicone dielectric grease but I should have and will get some and redo the connections. Thankyou this is a really good suggestion as it will also protect from moisture getting in as well.
Another issue cleared up ...
Prior to correcting the original spark issue I had a major hesitation when accellerating. I atributed this to the ignition problem but the symptoms were exactly like a transmission starting to wear out and having the start of early slipage when starting until things warmed up. Surprizingly the hesitation is gone (I expected this) but the slippage is also gone as well. I did not expect this.
Schrade
07-25-2009, 06:34 PM
I've recently had trouble starting my blazer intermittantly
Seems like if the weather is damp or rainy it won't start.
I do not even get a misfire when attempting to start
I've checked the fuel pressure and I have aprox 58 psi prior to turning the key.
I did get going during damp weather ... must have been a fluke ... lol
I noticed that I had a nice spark dancing between the ignition coil wire boot at the base and the ignition coil heavy metal "magnet" piece that runs through the center of the coil.
Aha ... that would definately cause starting failure if things are damp :)
I've replaced the spark plug wires, Distributor cap and rotor (general maintenance, need to be done anyway).
And the sparking still happens.
I replaced the ignition coil and the spark is still there ... although not as pronounced.
I've done my best to ensure that the coil connection wire boot is fully seated ... and still I get a spark that comes from the bottom of the boot to the coil magnet. It jumps about 3/8 inch.
Any suggestions on how I can stop this from happening?
Has anyone seen this sort of thing before?
Arcing is likely caused by to much resistance somewhere in the coil-to-plug(s) circuits. It's just like water in a line - if it can't flow, it's gonna' MAKE a hole in the line somewhere, so that it can get OUT.
Your wires HAVE TO be routed properly too. New wires that are misrouted could definitely cause this problem, as well as old wires. AND, this arcing will cause EMI, which will cause false codes, same as a nuke will. Wouldn't have believed it if I hadn't read it in my vette FSM (after chasin' 3 false codes for 9 weeks summer '08, fully documented photo-diags too :eek::eek::eek: )
Seems like if the weather is damp or rainy it won't start.
I do not even get a misfire when attempting to start
I've checked the fuel pressure and I have aprox 58 psi prior to turning the key.
I did get going during damp weather ... must have been a fluke ... lol
I noticed that I had a nice spark dancing between the ignition coil wire boot at the base and the ignition coil heavy metal "magnet" piece that runs through the center of the coil.
Aha ... that would definately cause starting failure if things are damp :)
I've replaced the spark plug wires, Distributor cap and rotor (general maintenance, need to be done anyway).
And the sparking still happens.
I replaced the ignition coil and the spark is still there ... although not as pronounced.
I've done my best to ensure that the coil connection wire boot is fully seated ... and still I get a spark that comes from the bottom of the boot to the coil magnet. It jumps about 3/8 inch.
Any suggestions on how I can stop this from happening?
Has anyone seen this sort of thing before?
Arcing is likely caused by to much resistance somewhere in the coil-to-plug(s) circuits. It's just like water in a line - if it can't flow, it's gonna' MAKE a hole in the line somewhere, so that it can get OUT.
Your wires HAVE TO be routed properly too. New wires that are misrouted could definitely cause this problem, as well as old wires. AND, this arcing will cause EMI, which will cause false codes, same as a nuke will. Wouldn't have believed it if I hadn't read it in my vette FSM (after chasin' 3 false codes for 9 weeks summer '08, fully documented photo-diags too :eek::eek::eek: )
skyzend
07-27-2009, 06:23 AM
Thanks cbec1999 ... you are exactly correct. The original arcing and starting problems were atributed to old wires, distributor or rotor. All were replaced. The similar arcing problem I experienced after the replacement was the incorrectly seated spark plug boot.
Again, a scenario that you proposed.
As for rooting the wires ... correct rooting can be tedious but luckily my chevy blazer engine has the original rooting guides ... many of them with good condition wire holders. They do a nice job of ensuring a nice wiring path with no abnormal kinks. These just took all the guesswork out of wire placement.
Again, a scenario that you proposed.
As for rooting the wires ... correct rooting can be tedious but luckily my chevy blazer engine has the original rooting guides ... many of them with good condition wire holders. They do a nice job of ensuring a nice wiring path with no abnormal kinks. These just took all the guesswork out of wire placement.
534BC
07-28-2009, 08:50 AM
Did the loose boot cure an intermittent no-start?
drdd
07-28-2009, 12:45 PM
are you related to BlazerLT ?
To old_master.
I can appreciate that you have 30 years of experience, but you need to change your approach. Telling me to use certain parts or I will undoubtably have problems. This whole discussion may have been avoided if you had phrased the comment as a suggestion rather than a statement of fact. I re-emphasize that I have used many different non high end parts and when properly installed have served me well.
Your comment on the amount of voltage to ignite a fuel mixture is totally bogus ... you need to go back to school. The ability for fuel to ignite whether lean or rich is strictly related to the quality of the spark. A crappy spark plug will not ignite either with any voltage large or small as well as a good plug with just enough voltage to get a clean spark. More voltage is an overcompensation that may be required to overcome poor wiring or connection before the current makes its way to the plug. If your coil is functioning properly and you have functional wires and distributor to ignite any fuel mixture that an injector can provide (if the injector is clean and functional) ... remember that if minimum fuel pressure requirements are not met then the injecctor will not fire and all bets are off. Of course my comments are made for a domestic engine and not one with performance compression RPM and cam configurations.
Also, I have checked the plugs and I am not running with a lean fuel mixture ... plugs don't lie ... my fuel mixture is good, the fuel pressure and injectors are regularly cleaned and have run fine for a long time and they continue to do so.
To Blazee,
Thank you ... your comments come across as more of a suggestion with options. I can appreciate your support for old_master, but I'm sorry, I like to tell it like it is and to start jumping to a cause right away (lean fuel), tell me a totally false secondary charge that shows up at the coil story and finally tell me I will absolutely have trouble without certain parts when its not true sounds irresponsible when coming from a seasoned technician.
Your comment about certain parts fouling up prematurely, I can see this but more often than not a good technician will look further to the root cause rather than just replacing with a more fault tolerant part.
My experience has shown that other demons are usually at work in cases like this.
To both of you and anyone else interested.
I took my own advice and investigated the possibility of high voltage not reaching a spark plug thus causing the high voltage to find an alternate route to ground (from under the coil boot). Success, The spark plug boot that is deep behind the steering column was not properly seated ... difficult to get a hand in there ... even when trying from underneith or going through the driver side wheel area. Reseated and now all is well. I did not use the silicone dielectric grease but I should have and will get some and redo the connections. Thankyou this is a really good suggestion as it will also protect from moisture getting in as well.
Another issue cleared up ...
Prior to correcting the original spark issue I had a major hesitation when accellerating. I atributed this to the ignition problem but the symptoms were exactly like a transmission starting to wear out and having the start of early slipage when starting until things warmed up. Surprizingly the hesitation is gone (I expected this) but the slippage is also gone as well. I did not expect this.
To old_master.
I can appreciate that you have 30 years of experience, but you need to change your approach. Telling me to use certain parts or I will undoubtably have problems. This whole discussion may have been avoided if you had phrased the comment as a suggestion rather than a statement of fact. I re-emphasize that I have used many different non high end parts and when properly installed have served me well.
Your comment on the amount of voltage to ignite a fuel mixture is totally bogus ... you need to go back to school. The ability for fuel to ignite whether lean or rich is strictly related to the quality of the spark. A crappy spark plug will not ignite either with any voltage large or small as well as a good plug with just enough voltage to get a clean spark. More voltage is an overcompensation that may be required to overcome poor wiring or connection before the current makes its way to the plug. If your coil is functioning properly and you have functional wires and distributor to ignite any fuel mixture that an injector can provide (if the injector is clean and functional) ... remember that if minimum fuel pressure requirements are not met then the injecctor will not fire and all bets are off. Of course my comments are made for a domestic engine and not one with performance compression RPM and cam configurations.
Also, I have checked the plugs and I am not running with a lean fuel mixture ... plugs don't lie ... my fuel mixture is good, the fuel pressure and injectors are regularly cleaned and have run fine for a long time and they continue to do so.
To Blazee,
Thank you ... your comments come across as more of a suggestion with options. I can appreciate your support for old_master, but I'm sorry, I like to tell it like it is and to start jumping to a cause right away (lean fuel), tell me a totally false secondary charge that shows up at the coil story and finally tell me I will absolutely have trouble without certain parts when its not true sounds irresponsible when coming from a seasoned technician.
Your comment about certain parts fouling up prematurely, I can see this but more often than not a good technician will look further to the root cause rather than just replacing with a more fault tolerant part.
My experience has shown that other demons are usually at work in cases like this.
To both of you and anyone else interested.
I took my own advice and investigated the possibility of high voltage not reaching a spark plug thus causing the high voltage to find an alternate route to ground (from under the coil boot). Success, The spark plug boot that is deep behind the steering column was not properly seated ... difficult to get a hand in there ... even when trying from underneith or going through the driver side wheel area. Reseated and now all is well. I did not use the silicone dielectric grease but I should have and will get some and redo the connections. Thankyou this is a really good suggestion as it will also protect from moisture getting in as well.
Another issue cleared up ...
Prior to correcting the original spark issue I had a major hesitation when accellerating. I atributed this to the ignition problem but the symptoms were exactly like a transmission starting to wear out and having the start of early slipage when starting until things warmed up. Surprizingly the hesitation is gone (I expected this) but the slippage is also gone as well. I did not expect this.
skyzend
07-28-2009, 01:04 PM
response to 534BC ...
No, the original problem was an intermittant no start. Accompanying symptom was visible sparking from the bottom of the coil boot. More prominant in damp weather. I attribute the sparking to aged wiring and/or worn distributor rotor, or possibly the coil its-self. I'd never seen this before from under a boot and was suspecting a crack maybe... still not sure.
I corrected the above which corrected the intermittant no start, but there was still a sparking although not as prominant. I analyzed out loud (here) and investigated further ... This was attributed to the loose sparkplug boot connection.
To drdd ... not related to BlazerLT ... don't know how to take this question ... could be a dis??? :)
No, the original problem was an intermittant no start. Accompanying symptom was visible sparking from the bottom of the coil boot. More prominant in damp weather. I attribute the sparking to aged wiring and/or worn distributor rotor, or possibly the coil its-self. I'd never seen this before from under a boot and was suspecting a crack maybe... still not sure.
I corrected the above which corrected the intermittant no start, but there was still a sparking although not as prominant. I analyzed out loud (here) and investigated further ... This was attributed to the loose sparkplug boot connection.
To drdd ... not related to BlazerLT ... don't know how to take this question ... could be a dis??? :)
534BC
07-28-2009, 02:45 PM
I'm a bit more unclear than before, It seems it is no, but yes. Anyways, glad it is fixed.
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