1997 S-Blazer stalling

EGR valve.

~KJ/TLGM

acceleration

That's the part that I was suspecting.

I'll replace it this weekend, and hopefully fix the problem.

Is it common for these to fail?

Thanks! Matt

"KJ" wrote

Don't go throwing $200 parts at it until you're sure what it is. This shorgun approach never works. Have the codes read at your local Autozone.

Doc

Hi Doc, The check engine light goes off again as soon as we shut the key off and restart the engine. I guess this sort of led me to believe that there weren't any codes being posted. Does the check engine light sometimes not light up for certain codes?

-Matt

Whenever the SES light comes on a code has been set. The light turns off because the light only remains on when the problem is present, shutting her off and restarting resets the duty cycle and keeps the light off until the problem is present again. Get thee to Autozone or Napa and have it scanned before you purchase anything. The light will not illuminate for certain codes.

Doc

You might wanna talk to a dealer first. There was a recall on the EGR valve and a free replacement offered. My Blazer (95) ate two of them in a year....and they ain't cheap. But poor design causes them to get choked with carbon. You can clean one (Techron gas additive will do it) and get another year or more out of it also. Symptoms are, wanting to stall out unless you keep foot on gas, and a definite loss of power. Every stop light and stop sign are an adventure!! .

Hello again, I took a trip over to Autozone this evening. The truck stalled 4 times during the round trip, but the scanner revealed nothing. It said that everything was OK, which set me back to square one.

I explained the problem to the guy that ran the scan for me. He said that it seemed to him like it was idling a little rough, and that a new set of plugs and wires might be all it needs.

The Blazer has about 80,000 miles on it. I've only owned it since 50,000 (about 2 years ago), so I don't know if they're the originals or not. I guess new plugs and wires aren't out of the question, but it almost seems too simple.

Any thoughts?

-Matt

No codes? That's weird as hell. When the SES light comes on it sets a code and it's stored in memory until it clears itself after a predetermined # of duty cycles or is erased.

Could just need a tune up if it's 80k on the originals. Pull a few plugs and have a look. If they're shot replace them. Run the engine at night in a DARK place with the hood lamp off and look for a fireworks show. If you see one, the plug wires are shot and need replaced.

Doc

I still think he has an EGR problem. There not *too* hard to pull, I'd try a u-pull-it-yard or trying a friends known working. The latter would probably be the best. That should get him someplace.

~KJ/TLGM

Yours is a vacuum actuated valve that runs $50, his is an electronic, linear valve that runs $200. $50 is worth a gamble, $200 is not.

Doc

I don't like a $5 guess. That's why I'd try someone's known-working EGR to see if it fixes the problem....

~KJ/TLGM