Question about 1992 GMC Sonoma

2 Answers

1992 gmc sonoma pick up egr system diagnostic procedures. help?!

My truck just quit on me getting off the freeway. I jumped it and it started but I had to keep my foot on the gas because it kept trying to die. When I got home the truck wouldnt start again without a jump. All the pressures were fine. I fixed the starting problem by cleaning the battery posts and no more need for jumps. I've been told the problem is the EGR system. Truck symptoms as of now are smooth fast idle on cold start, rough serging idle when hot and when throttling up. So how do i fix it?? Help! Please?

The system types are:
engine tag:: 4.3 liter n3g4 3tbxe b2 nbo- 3e
house routing tag:: catalyst egr/twc/ho2s
vin # :: 1 g dcs14w8no820230

thank you.

Posted by on

  • Anonymous Jan 21, 2009

    same problem.... I have cleaned the EGR and replaced the O2 sensor, still having issues. My truck has been acting like this for 2 weeks. The only code that our GM TECH1 scanner will read is that the exhaust is fuel rich. I work in a Chevrolet dealership service dept. and we are having trouble finding the problem. BTW, I have noticed a rotten egg smell and drasticaly increased fuel consumtion. Early morning cold start the truck runs fine, once it gets warmed up, the surging and stalling begin. Also, it seems as though mine is also dropping spark, as if the ignition system is completely cutting off then refiring.



2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Top Expert:

    An expert who has finished #1 on the weekly Top 10 Fixya Experts Leaderboard.


    An expert that got 20 achievements.


    An expert that got 10 achievements.

  • GMC Master
  • 77,169 Answers

Exhaust Gas Recirculation systems do not cause you symtoms, when the EGR fails it leaks exhaust gases into the cylinders, this causes a very very rough idle and a stall, the valve gets hot when it leaks at idle. Run a self test on the ECM and try to get any trouble codes stored in it, Kragen auto I hear does this for free.

Posted on Oct 19, 2008

  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert that got 5 achievements.


    An expert whose answer got voted for 20 times.


    An expert who has written 20 answers of more than 400 characters.

  • Expert
  • 38 Answers

To trouble shoot your rotten egg smell... have you checked your coolant level. Usaully when you smell a rotten egg smell from the exhaust it indicates that your engine is ingesting coolant. Possible causes are: blown head gasket, cracked waterjackets in one or more cylinders, intake manifold cracked or leaking manifold gasket at the heads. My buddy and I just got done changing out his intake manifold along with waterpump gasket, cooler line O-rings and oil pan gasket. He was finding that he was slowly loosing coolant, but nothing on the ground. I went to his exhaust and smelled it as it was running and it smelled like rotten eggs. That told me that he was ingesting his coolant. We checked around the intake manifold (plentum) gaskets and could see that things were looking damp. My friend did some checking around at the dealer and he found out tha GM has a lawsuit against DexCool (orange coolant) because their product was eating away the seals and mixing with the oil. My friend is driving a 2002 GMC Seirra (96,000 mi - 2nd owner) with the 5.7 liter (Aluminum heads). We pressure tested the coolant system and found that some of the coolant was coming out around the water pump seal as well. GM said that his truck wasn't on the list yet, but it could make the list soon so he's instructed to keep in touch. We also noticed the O-ring on the cooler line showed signs of failing because of the white crusty stain that tracked down the base of the head to the manifold. During all of this his truck seemed to be running fine. Before things got worse we decided to pull the Plastic (on his engine) intake manifold to look at the clip-on style gaskets. They looked bad. They are made of a type of silicone rubber and they looked like they were chemically melted or just like they were getting mishapen (kind of wavey looking in area's). We went to ADVANCED AUTOPARTS store (where we have received years of outstanding advise and quality parts) and queried the parts specialist who told us to also (because it's plastic and there have been known problems with the OEM intake manifold) check with a straight edge, the levelness of the mating surface on the intake manifold (gaskets removed of course). Numbers 2 & 4 intake ports had about a 0.040" gap under the straight edge. Even the silicone style gaskets when compressed can't bridge that gap effectively while under pressure. We searched the intake for cracks as well and found none, but to correct the intake problem we had to order a new intake from ADVANCED AUTOPARTS STORE and the new OEM standard replacement comes with a solution to the known problem and had thicker mating surfaces and the gaskets were embedded in the new design. while having the water pump off, and the intake manifold off we took the oportunity at and changed out his timing chain and gears along with his oilpan gasket that came with the FRAM water pump gasket kit. After making sure that his timing chain sprokets where aligned we put everything back together but opted to change out the AC Delco plugs for NGK Irridiums and OMG... Brother, there was no more leaks, no more throttle hesitation which is standard with OEM plugs and the truck set you back IN YOUR SEAT. The backend got started to float from left to right a rolling start of about 15mph to get out ahead of traffic that was just leaving the light and because of the recommendation of the reps at ADVANCED the truck runs like a Raped Ape. I litterally found myself searching for a break pedal on the passenger floor. LOL My buddy said that truck has NEVER run like that in the all the years that he has owned it. It always ran very clean and nice, but HOLY COW!!! He was grinning like the little school boy that just got his first kiss out on the school playground by cute little Lisa. Best of all... No more leaks and no more rotten egg smell.

You may not have all of these things going on with yours or maybe you do, but to address the smell I would look the engine over and pressure test the engine cooling system and if you're using the Orange coolant, GET RID OF IT before you spend approx $800.00 like my buddy. The coolant could also be causing your rough running engine. Coolant will choke up a cylinder causing your vehicle to run rough or irratic. We did the work in 2 days taking our time and making it right and he hasn't been happier ever since.

Ford Guy

Posted on Mar 14, 2009


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

2 Answers

97 sonoma 4.3 csefi hesitates slightly when cruising at freeway speeds stops hesitating when accelerating

A bad EGR would probably set a code. You may have a dirty throttle body.

Jan 30, 2015 | 1997 GMC Jimmy

1 Answer

Where is the EGR valve located on 2002 gmc Sonoma 2.2 engine

Do you notice problem like vehicle stalls,low idle, then it can be due to faulty EGR valve.
Also is there check engine light ON.If yes,then get the vehicle scanned.It will tell what is the problem as per error codes.

For EGR valve location and more details,click the link below:---
These will help.

Oct 21, 2012 | Cars & Trucks

1 Answer

Code 21 for a 92 gmc snoma

It really depends on WHICH ENGINE your GMC is equipped with. The possible engines for GMC Sonoma for the 1992 model year are:
2.5L, 2.8L, 4.3L(VIN code "W"), and 4.3L (VIN code "Z").

This is really need-to-know information if you would like help diagnosing and repairing your engine control system.

Anyway, you probably have a problem with your TP sensor or TP sensor circuits, but I am not sure without looking it up by application.

Mar 05, 2012 | 1992 GMC Sonoma

1 Answer

I have a 1992 GMC Sonoma 4.3L, and once in awhile, when I go to take off, the truck will start to sputter and die. It starts back up after I actuallu floor the gas pedel, then the idle is really high?...

It is possible and also a cheap easy place to start. I would also test your fuel pump by perfoming a fuel pressure test by using a fuel pressure gauge. When was the last time you tuned up your truck? You may also have an EGR valve that may be sticking open. You may have other sensors that may be causing your problem but you will need to be plugged into a scanner to help troubleshoot those.

May 02, 2011 | 1992 GMC Sonoma

1 Answer

1996 gmc sonoma 2.2 engine

For 1996 GMC Truck Sonoma 2WD 2.2L SFI OHV 4cyl
The EGR Valve is located under hood, center, rear engine area, mounted top rear driver side of engine.


Fig. 11: Unfasten the EGR valve retaining bolts...


Fig. 12: ...then remove the EGR valve from the vehicle

I really hope help with this (remember rated and comment this post).

Mar 10, 2010 | 1996 GMC Sonoma

1 Answer

1992 GMC Sonoma - 4.3l cannot start after stall and knocking.

Sounds like an engine sensor, EGR valve or O2 sensor has failed. First thing to do is to look at the engine trouble codes to pin down the failure. You can usually borrow an OBD1 code checker from your local parts store.

Mar 11, 2017 | 1992 GMC Sonoma

1 Answer

92 GMC EXT Cab chugs after it warms up

Its the EGR valve. My personal solution was just to disconnect the vacuum line from the EGR solenoid. Take the breather off. Looking at the motor from the front of the truck, look to the left of the throttle body(injectors) and find a small electronic device with two vacuum lines attached to it. Take the vacuum line on the very back and unplug it.

Feb 16, 2009 | 1992 GMC Sonoma

Not finding what you are looking for?
1992 GMC Sonoma Logo

871 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts


Level 3 Expert

77169 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22258 Answers

Ronny Bennett Sr.
Ronny Bennett Sr.

Level 3 Expert

6927 Answers

Are you a GMC Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides