15th Apr 2007, 10:28

I have a 95 S10 LS with a high output engine (multi-port) changed the EGR valve and the thing won't run? Any ideas?


14th Jun 2007, 13:03

I have a 93 chevy blazer Vortec engine, check engine light just came on, I've been driving it for over a week, just now had this pop up? Any ideas? I was driving fast today trying to get somewhere in a hurry?

6th Jul 2007, 21:12

I have a 2003 gmc envoy can any one please tell me where the EGR valve is located???

Thanks feel free to email me dh11670@charter.net.

7th Jul 2007, 14:00

I have a 2000 S10 4.3. Have some driving issues, but idles fine and no problem with breaking. I noticed most complaints are 0n 94 - 95 - 97 motors, has GM changed the design or what. I saw no post on 2000 or newer.

23rd Aug 2007, 10:38

I own a 94' S10 Blazer with the Vortec engine. I have owned 2 blazers, the 1st had the TBI 4.3, never had a problem.

My Vortec has had all the same problems listed in the forum. I've replaced the fuel pump twice, the CPI, spark plugs, EGR x 2 and have cleaned the upper plenum and EGR several times. I have not tried the mesh gasket or using a higher grade fuel, but after all the reading I definitely will.

The problem I have had lately is my engine running hot, and coolant spraying out of the upper radiator hose. I have tried replacing the hose and it did not fix the problem and just recently I changed out the Thermostat thinking it was not opening. After all this work the coolant still leaks, thinking the radiator now. Also my truck will not start now, It had been acting sluggish when starting recently. The plugs are new, about 3 months old, but I did not replace the distributor cap, could this cause the problem of not starting?

22nd Sep 2007, 19:38

I have a 94 Jimmy 4.3 with some of the same problems. My idle is great and it seems to run great for about 20 min. When I stop and accelerate it dies and stalls out. I have to get out in traffic and shoot starting fluid in throttle body. It starts up, but very sluggish. Only happens when I give it the gas. Thanks brureb28@aol.com.

25th Oct 2007, 15:07


Time to clean the egr again.

14th Feb 2008, 18:40

OK I have a 94 gmc jimmy it seems to have a egr going bad. But I have a stupid question. do I have to remove the intake to get a better hold on this and should I use this fancy fiber filter gasket?

25th Feb 2008, 20:36

2/25/08 I also have a 94 4.3 blazer with many of the same problems listed in this forum, I must say I'm a little discouraged by all the bad luck everybody is having. Would like to see more info on the egr upgrade in the ECM that one follow talked about.

13th Mar 2008, 20:43

I have a 1994 S10 blazer, and I just removed the egr valve again. I put a blank plate on and it runs great. 2 years until emission testing. Have to go get my egr valve and my sledgehammer now, its the only way to fix this problem.

14th Mar 2008, 07:27

This page is helpful.

24th Apr 2008, 22:01

1997 GM 1/2 ton 4.3L. Starts okay, but it runs very rough especially when cold. If I accelerate hard it runs good. When I get to cruising speed it runs like garbage. It has a 5 speed so you can really feel the jerking motion of the engine running rough. IT eats distributor caps. The contacts get corroded almost instantly. Replacing sometimes makes the rough running go away. I bought it for $1500, and only drive it once or twice on the week-ends, so I guess fixing it is my new hobby. Could be worse, I could be drinking instead.

I think I might make an EGR cover plate as mentioned earlier. I might create more NOx, but hey, I only drive it 10km/year.

8th Nov 2008, 16:59

94 Blazer 4.3 Vortec. When idle, the motor revs up so high I have turn it off. Any help?

9th Nov 2008, 09:31

I have a 95 S10 Blazer that has the EGR problem of clogging. I'm going to use some SS screen and press it into my gasket. I hope it works. The screen is about the same size as a Tomco gasket.

14th Nov 2008, 00:05

First of all, you can buy a $2000 car that will run better than any S10 with a 4.3 Vortex with CPI problems, especially if you have to take it to a mechanic.

I have plenty of mechanical experience, and these designs can drive you crazy, not to mention the cost.

I can list all of the problems I have fixed on my S10, but that seems to prove only how stubborn I am about a mechanical problem I can't fix. Donate the car and buy a junker that runs OK.

19th Mar 2009, 22:25

I bought this 94 Blazer 4.3 CPI... nothing.. I mean NOTHING but problem after problem after problem... you wanna list? Here it is..

Heater core

A/C compressor + went ahead and made it all new.. (wasted $$)

Rebuilt heads.. cracked heads burning water.

CPI unit + spider.. it hurt so bad... $$$.

TPS sensor.

Fuel pump + pickup.

Fuel pressure regulator.

It would make it about a month between problems.. then I would get the call.. and now.. EGR problems, I owe $800 on this pile of crap.. I have never been so angry in my life at a vehicle.. it is super clean and nice fully loaded, but I can't handle the problems anymore..

My Sonoma 4.3 TBI had 332,000 miles on it, reliable as taxes always... I thought they improved the design... they FAILED so bad.. I am at my wits end here and this thing is GONE.. can't handle it anymore.. could buy a 500 Honda and it would be 10 times as reliable. Blazer has 210,000 miles... Buyer beware!! I feel all of the posters pain here. Chevrolet needs a lawsuit over this one with the lemon law. GL my problems are going away ASAP.

PS Anyone wanna buy a good Blazer? Real reliable.. aahh humor is not helping...

25th Apr 2009, 19:31

I just came in from fixing this same thing.

I was reading where this guy said to go out and start the truck, then keep tapping the EGR at the base till the piece of carbon comes out, you can hear it getting a little better every time you tap it, I did about 15 taps and the idle smoothed out, for how long I don't know, you can get to the base on the passenger side with a small ballpen, and for those who don't know where the EGR valve is, it is right under the air intake behind the A/C pump.

5th May 2009, 22:37

94 Jimmy VIN W here, had all of these problems and found a post about the TOMCO screen filter which worked great! I appreciate everyone for sharing that info.

Don't try kicking the throttle as suggested though, I used to do that and blew up and engine doing it, now I'm on a second used engine with Tomco Screen.

When EGR problems occur, it had a very rough idle and poor performance at low speeds. At higher speeds, it actually wasn't too bad since I guess the EGR valve goes open 100% anyway.

I've had some strange problems with it, but it sure is a nice vehicle, especially with the 4 new Michelins on it!