My Blazer has another thing wrong

[Nodakskip]

Ok. We had gotten the glasspack muffler taken off and put a new one on. With in a few days it was riding ruff and shaking. My uncle drove it and said the timing was bad "It's missing a bit." Also the sparkplugs were not all working so my new muffler tail pipe was black.

We changed the sparkplugs in a tune up. The guys said that who ever did it the last time only changed one side since the other side was hard to get to. So now I have all new plugs. It seems to run fine....

However twice now its done something wierd.

It seems to want to take off is the best way to describe it. It has times where it will run fast then get stuck in mid reving (not sure if thats even a word.) But I will hear a "vroom, vroom, vroom" then it takes off a bit and is hard to push the brake and coasts a bit.

Anyone know what this is?

94 Blazer.

[rlith]

Do a full tune up. Pull and clean the EGR. Check all vac hoses for dryrot of cracks. See if that helps. l

[blazee]

Clean you IAC valve. If it sticks it will cause your engine to rev like that. Are you getting any codes?

[Nodakskip]

Originally Posted by blazee

Clean you IAC valve. If it sticks it will cause your engine to rev like that. Are you getting any codes?

I am not that big of a car person. How would I know if I am getting a code? I have seen it talked about here on the boards, but I have no idea where a Blazer would say a code.

Also should mention that my uncle (before this) had gotten a new air filter and pcv valve.

Also I have skimmed the board here and some talk about air hoses being a problem. I just want to tell you guys everything that is going wrong to better be able to fix it.

The heat/cool controls no longer work on high. Also I have heard two large hissing noises comming from that area of the dash in the last day or so. May mean something, may not.

[blazee]

The check engine light comes on to let you know that there are codes.

Yeah, it sounds like you have a vacuum leak. I was hopeing that it was just the IAC valve, because vacuum leaks can be hard to find. See if you can tell where the leak is and repair it.

[Nodakskip]

Just wanted to do an update. Last night I tried driving it to my dads house and it killed on me and was running rough and missing. My dad drove it to a car place across town and found that when it would start to rumble and die... he had to add a little gas and it would stay on. (it would only nearly die on when going slow towards a stop sign or traffic light)

But my step mom who followed us said she could smell gas as we drove and the check engine light came on and stayed on.

Plus Ive talked to the place we brought it to and they say that the scanner they have to tell what code it has is not working so I might as well come and pick it up.

Also they say its running fine, but it sure was not last night. We are going to get it and take it to a place that has a working scanner.

[BlazerLT]

Listen......

Do a tuneup.

Set the timing with a timing gun and the timing wire unattached.

Replace cap and rotor, fuel filter, air filter, PCV valve, plug wires.

And change your oil ASAP, your oil will be full of fuel and that is destroying your engine.

[Schrade]

Originally Posted by Nodakskip

I am not that big of a car person. How would I know if I am getting a code? I have seen it talked about here on the boards, but I have no idea where a Blazer would say a code.

Also should mention that my uncle (before this) had gotten a new air filter and pcv valve.

Also I have skimmed the board here and some talk about air hoses being a problem. I just want to tell you guys everything that is going wrong to better be able to fix it.

The heat/cool controls no longer work on high. Also I have heard two large hissing noises comming from that area of the dash in the last day or so. May mean something, may not.

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This is your vacuum leak!!! Will cause yo-yo, or loping, or surging RPM's...

Gosh guys! I'm surprised you missed this one. That's what I usually do!

Ya' gotta fix this vacuum leak, Noda. Some vehicles have vacuum- actuated heat/cool controls. Yours not working, and a hiss, I think addresses both of these problems. Depending on how the vacuum hoses are damaged, you might just clip off an eighth of an inch, and re-connect it. If you're lucky, it's just disconnected. I think also there's NOT two hisses, as in simultaneously - I don't know how you'd be able to tell that. When you say two hisses, do you mean in sequence? Maybe two hisses, or more, coinciding with the motor loping?

Come back on this one, Noda...

Also did you say that the code light wasn't working? When you turn on the key, before you crank the engine, is one of the dashlights a 'SERVICE ENGINE SOON' light? This should be near the top of the list to fix, if broken...

[Nodakskip]

Ok an update. It seems that the service engine light is the ERG or EGR. I always get the name mixed up. We've had it cleaned before. But from what I was told second hand (I was not the guy to take it to the shop) that it needed a new one and would be around 800 to get and replace.

Anyone know of any websites to get a new part cheaper?

I am also going to ask about the leak in the vacume tubes with the heat/air.

<<When you say two hisses, do you mean in sequence? Maybe two hisses, or more, coinciding with the motor loping?>>

No, i heard them when I shut the blazer off at times. It was always just one hiss at a time, not together.

[blazee]

You need to go to that shop and kick that grease monkey's ass for being such a scum bag. Depending on which EGR valve you have, the price will between $40 - $150. And it takes about 4 minutes to install. Usually they can just be cleaned.

After reading your old threads...this seems to be a recurring problem. I suggest you check to see if your CPI is leaking.

10-24-2004

Originally Posted by Nodakskip

Ok, first my EGR had to be opened with a computer and then taken out and cleaned after the problem didnt go away. Also some wires were sparking and the mechanic said I was losing horsepower.

They replaced the wires and I do notice a lot of more power, but I am having trouble with the breaks.

The first two days the breaks were very tight. Then they were loose, then tight for a day. Then loose. Now they are very tight again. Also I noticed that when I slow down to turn onto a new street, but dont stop at a stop sign just turn, it seems to speed up when I am going around the turn with out me hitting the gas.

04-23-2005

Originally Posted by Nodakskip

Ok, I have a 94 blazer. We've been putting a lot of money into it already so I hope I dont have to put more in.

One of the things in the past I have had done is the erg thing since it had a bit of carbon stuck in it. It would drive fine then shake like crazy and shut off at a stoplight. I had to restart it at least twice. They hooked up the computer to the dash and said they fixed it, then the next day it did it again. They took it out and cleaned it and havent had any trouble.

That was months ago.

Now...

I have two startings.
1. A smooth start that runs mostly fine.
2. A jerk start that seems to start before I fully turn the key.

The Blazer seems to shake a lot. Not as bad when the erg was going bad, but shaking. Some times when hardly any breaks are used. Also when I get to a stop (stop sign or stop light) it is fine for about 25 seconds then it starts to shake a lot.

Also in the last two days I have noticed that sometimes it drives in a lull then suddenly revs up and jerks a tiny bit after I go after stoping at a light or stop sign.

And I have not watched it too much, but I think I might be loosing gas milage.

My brother had this blazer before me and put on a glasspack mufler and I have allways thought any shaking was do to that thing. Could this mean the glasspack is going bad or clogged up?

[Nodakskip]

Originally Posted by blazee

You need to go to that shop and kick that grease monkey's ass for being such a scum bag. Depending on which EGR valve you have, the price will between $40 - $150. And it takes about 4 minutes to install. Usually they can just be cleaned.

Ok I talked to my mom (step dad took it in) and she said they found other stuff along with the EGR. She only told me the EGR the first time I talked to her. And there is a computer print out list off all the stuff. But the place is closed till tueday because of the holiday.

I will post the list when I get it.

[BlazerLT]

Originally Posted by Nodakskip

Ok an update. It seems that the service engine light is the ERG or EGR. I always get the name mixed up. We've had it cleaned before. But from what I was told second hand (I was not the guy to take it to the shop) that it needed a new one and would be around 800 to get and replace.

Anyone know of any websites to get a new part cheaper?

I am also going to ask about the leak in the vacume tubes with the heat/air.

<<When you say two hisses, do you mean in sequence? Maybe two hisses, or more, coinciding with the motor loping?>>

No, i heard them when I shut the blazer off at times. It was always just one hiss at a time, not together.

That guy is a piece of shit.

$800? Hell it is only $150 here.

[Schrade]

Vacuum leak Noda!!!!!!!!!!!!! Vacuum leak is causing the surge!!!!!!!!!!!!!!!!!! Listen for the hiss while you're still in the driveway. Since you say you hear a hiss(es), and the heat/cool controls are vacuum actuated, and they're not working, YOU HAVE A VACUUM LEAK!!!!!!!!!!!!!!!!!!!!!!!!!!!

[BlazerLT]

Originally Posted by cbec1999

Vacuum leak Noda!!!!!!!!!!!!! Vacuum leak is causing the surge!!!!!!!!!!!!!!!!!! Listen for the hiss while you're still in the driveway. Since you say you hear a hiss(es), and the heat/cool controls are vacuum actuated, and they're not working, YOU HAVE A VACUUM LEAK!!!!!!!!!!!!!!!!!!!!!!!!!!!

Back slowly away from the caffeine bro.......

Put the coffee down.........

[Nodakskip]

Ok another update. We've got the Blazer hooked up to a scanner and this what they say I need...

1. ACDELCO EGR VALVE
Remove & Replace EGR Valve
1. Victor Valve Cover Gskt Set
1. Victor INT Manifold Set
Remove & Replace Intake Manifold Gasket
+Cruise Control interferes add
+Elect Eng Sys interferes add
Change Oil and Oil Filter
1. Filter Fleet
5. VAL10-30V

I am going to make sure the topic of a vacume leak is looked at.

And the sheet says my Blazer is...
1994 Chevy S10 Blazer V6-262 4.3L