Hard start '92 v6 3.1L

[paulsantangelo]

Hey All:

I wonder if someone could Help me with some suggestions here.

After replacing cap, rotor and cables last year, I'm having an issue with Hard starting.

Let say the Rodeo is driving for 10 - 20 minutes. I shut it off to fill the tank or its just off for 5 minutes (both conditions, this has occured), The engine has a hard time starting.

The only way I can get it to start is, to time the key with the gas pedal. What I mean is that I crank the engine, until it starts cranking twice as fast as normal, (a few seconds more than normal), Then release the key and push the gas petal to the floor. What happens is that the engine will be rough at 0 -500 RPMs for about a second. Then it will either die, or the RPMS will increase.

If I do not use the gas petal, it takes longer to start.

Its interminent, but mostly reproducable if the conditions above are met.

I dont even know where to start, I replaced the parts because of white spots on the cables. Someone told me those were caused by arcing.


The issue misterously went away in summer and fall, but seems to be back.


Any ideas would be great!

-paul

[bengalsfan]

Originally Posted by paulsantangelo

Hey All:

I wonder if someone could Help me with some suggestions here.

After replacing cap, rotor and cables last year, I'm having an issue with Hard starting.

Let say the Rodeo is driving for 10 - 20 minutes. I shut it off to fill the tank or its just off for 5 minutes (both conditions, this has occured), The engine has a hard time starting.

The only way I can get it to start is, to time the key with the gas pedal. What I mean is that I crank the engine, until it starts cranking twice as fast as normal, (a few seconds more than normal), Then release the key and push the gas petal to the floor. What happens is that the engine will be rough at 0 -500 RPMs for about a second. Then it will either die, or the RPMS will increase.

If I do not use the gas petal, it takes longer to start.

Its interminent, but mostly reproducable if the conditions above are met.

I dont even know where to start, I replaced the parts because of white spots on the cables. Someone told me those were caused by arcing.


The issue misterously went away in summer and fall, but seems to be back.


Any ideas would be great!

-paul

perhaps your timing maybe off, i know very little about cars but my tensioner was going bad on my rodeo and it caused my belt to loosen...and then the belt slipped and then the timing went off. when i tried to start it...the situation is similar to yours.

bengalsfan

[paulsantangelo]

Well thanks for that, but I have a timing chain, not a belt, but you do bring up something and thats when I got a new timing chain, they set the timing at 0 degrees, The spec was 10 so, my brother and I changed it to 10, maybe we missed!

Its an easy check.

[Cat Fuzz]

Sounds like ignition timing.

[94twacker]

I was having the same problems with my 92 rodeo, try the fuel filter. Seriously mine was running real bad too, and I changed the fuel filter and it is all better now. Its like 20F outside right now and when I went out to start it and let it warm up it starts right up, no pushing the gas or anything. Its worth a shot anyways,cant hurt right?

[paulsantangelo]

Did you have any problems starting when cold or when warm? I only have trouble when warm. When replacing the filter, did you run into any problems, like gas spilling everywhere?

-thanks
paul

[94twacker]

all of the time, with the fuel filter you are going to get some gas coming out of the lines, you cant really help that because I dont believe there is a way to relieve the fuel pressure on the 3.1 since it is throttle body injected, so expect a little leakage.

[paulsantangelo]

I got my hands on a timing light, out it into bypass mode, but did not plug the EGR or purge vacuum lines, I didn't have plugs. My brother told me afterwards I can use electrical tape. Anyway I got 8 degrees instead on 10.

My question is how many degrees is changed when plugging those vacuum lines?

-thanks!

[paulsantangelo]

Ok, I plugged the vacuum lines, It made no difference, I tell you, those haynes books suck!

Not only do they give contradicting information (in the same chapter) but they got you doing things that are needless.

So, My brother and I changed the timing from 8 to 10 degrees, What a difference two degrees makes, wow. The rough idling went away and when I climb hills the pinging sound isnt as loud.

He even went to 12 degress which the car just purred, it was amazing, we left it at 10 because of factory.

I tried to reproduce the issue, Running the engine for a while and then shutting down for a few minutes. Twice I could not reproduce the issue, but there is something interestingly different and I'm not saying that this is solved, but the time to get the car started is different. Like .25 sec longer from when I turn the key to when I release it. Its quite interesting, I use to pop it and go, now I have to hold the key for a little longer, dont know if that means anything or not!

-paul

[brattygirl72]

Originally Posted by paulsantangelo

Ok, I plugged the vacuum lines, It made no difference, I tell you, those haynes books suck!

Not only do they give contradicting information (in the same chapter) but they got you doing things that are needless.

So, My brother and I changed the timing from 8 to 10 degrees, What a difference two degrees makes, wow. The rough idling went away and when I climb hills the pinging sound isnt as loud.

He even went to 12 degress which the car just purred, it was amazing, we left it at 10 because of factory.

I tried to reproduce the issue, Running the engine for a while and then shutting down for a few minutes. Twice I could not reproduce the issue, but there is something interestingly different and I'm not saying that this is solved, but the time to get the car started is different. Like .25 sec longer from when I turn the key to when I release it. Its quite interesting, I use to pop it and go, now I have to hold the key for a little longer, dont know if that means anything or not!

-paul

Paul,

I'm having the same problem with my Rodeo. I read a post that if you turn the key on and off 8-10 times and wait 3 seconds between each turn it will start right up. It's been working for me right now (until I take the truck to the shop on Saturday) but it's annoying to have to start my truck that way.
It's been a few days since your last post. Did changing to timing to 10 degrees solve your problem?

Thanks.

[paulsantangelo]

Hi there:

I haven't had a problem yet, but I go to get gas tomorrow, wednesday its .5 Cents cheaper, so thats why I'm waiting.

Interesting workaround you found, If you do the math 8-10 * 3 = 24 to 30 seconds not including the length of time is was off nor the time to turn the key, 1 second or 2.

When you say turn on and off, does that include cranking? Because I can tell you that I had to pop start her a couple of times, so I was out there for a while.

I'll be glad to post results tomorrow, but I wont consider this fixed for at least a month of trying to replicate it.

Did you have any work done on your engine, before this started happening? What engine do you have?

[paulsantangelo]

One other note, I didn't arbertraily pick 10 degrees, under the hood it the factory spec which reads that it should be set to 10 degrees, if you have the 3.1L GM V6 thats were you should be or higher, but not much higher, we had it at 12 and I'm almost willing to reset it at 12. But I need to be sure that the problem is fixed, first. The fact the it takes a little longer to start makes sense to me as to why sometimes she would not start, just hope I'm right!

[brattygirl72]

Originally Posted by paulsantangelo

Hi there:

I haven't had a problem yet, but I go to get gas tomorrow, wednesday its .5 Cents cheaper, so thats why I'm waiting.

Interesting workaround you found, If you do the math 8-10 * 3 = 24 to 30 seconds not including the length of time is was off nor the time to turn the key, 1 second or 2.

When you say turn on and off, does that include cranking? Because I can tell you that I had to pop start her a couple of times, so I was out there for a while.

I'll be glad to post results tomorrow, but I wont consider this fixed for at least a month of trying to replicate it.

Did you have any work done on your engine, before this started happening? What engine do you have?

I'm sorry I ment to say turn the key (only w/ out starting) on and off and wait 3 seconds w/ the key turned in the on position. I'm assuming that this trick is starting the fuel pump to prime the carb. Because I hear the fuel pump click on when I turn the key on. I'm not sure but it works. I have the 3.1 V6 as well. I just bought the truck last weekend so I haven't done any work to it yet and I'm not sure what the previous owner did to it. I going to get it checked out this weekend. Let me know how things go when you fill 'er up! Thanks!

[paulsantangelo]

Hi there:

Does the phrase swing and a miss tell you something about my success? I had the hard start again. The good news, it didn't last as long, but I did find out some good things during this episode.

First disconnected the bypass wire behind the kick panel by the driver side left foot (its a white/black wire, to be done with the key off). Tried to start but it did not. That was a good sign because that would have meant that the coil needs replacing.

I then removed the ignition coil wire that goes to the center of the distributor cap. The idea was to see if the coil was charging, it sounds like the strobe in a camera, a high pitched wine should be heard when charged. I didn't but it was very noisy at the gas station, not like my garage, so I had someone else crank the engine and I noticed that the exposed connection point on the coil was arcing. I've never seen that before, because I'm usally in the car cranking away, with of course the wire on the contact. What I can deduce from this, is that either the wire itself is bad or its not a spark problem. I did change the wire back to the original that was on there, its a bit shorter than the new one, I wonder if that might have something to do with it.

I also purchased today, Fram fuel filter. Its interesting to what you said! Prime the pump, I do hear the fuel pump operating when the car does not start, but I just wonder if the self cleaning fuel filter is done. In the 11 years that I had her, I dont believe I've ever changed the fuel filter. Perhaps its just coincidence that it all happen at the same time, well I wont be able to install the fuel filter until this weekend, so I will be testing the old cable in the meantime.

Please let me know what your mechanic finds out!

-Paul

[paulsantangelo]

I could not install the fuel filter, so I'm seeking help from my local service guy, I know, wimp, but its cold out there.

I did last week replace the coil wire to the distributer with the original (I saved them when I did the change out) and went to get fuel tonight. The engine did start although it was rough for the first second. I'm not sure what that means but I took a ohm reading off the new wire which came to 4700 Ohms. The original wire which is still on the vehicle, I'm not sure, but I can tell you that the original one is much shorter, than the one that I was having a problem with. This is a Conrad wire. There seems to be black deposits in the plug, not sure what that means either. I will Ohm the original wire out this weekend, I couldnt do it tonight because I had to repair the dishwasher!

-paul