This problem needs to end!!

[sasmosphere]

I'm gonna start from the begining...
16 yrs old & parents bought me 95 Lumina, 3.1 L. Low mileage & had no problems for almost a yr. Then the SES light started to show up about 1 outta the 15 times I would be driving. I didn't think much of it b/c it ran ok & wasn't on consistently. In the past 10 months, it's been coming on more & more. Took it to the dealer last fall & they told me they couldn't pull codes b/c it's too old & doesn't have the memory bank until 96's model, bullcrap. So I tried to get it to come on for them & to no avail.
@ this point it appears 70% of the time...& the kicker is that it specifically shows up between 40-60 mph; when the car's coasting w/out cruise or my foot touching the gas pedal, & also right as the brakes are applied. I started working @ a shop 10 months ago, so I had a co-worker look @ it earlier this yr in spring. He pulled an EGR malfunction {can't remember code #} & recommended a new 1. So assuming he knew what he's talking about, purchased the $200-something valve & replaced it. It's been coming on more than ever since it's been replaced & we're all stumped & don't wanna replace every possible problem...
When the light is on, the engine runs like garbage; it takes more gas to accelerate like it normally would & just really sluggish. It's never died on me tho either & it's never on when I 1st start it up, only between 40-60 mph. I know EGR codes are common for showing up in these things...but what is the deal w/mine??!? Somebody has to know something...!!!!!!!

[jd-autotech]

ok retreiving the code and sharing that info is job # 1 -when then the light comes back on ethier have it scanned or poke a paper clip between the two top right terminals on your aldl connector under left side of dash and watch the check engine light flash and count the flashes,qiuck flashes represent 1 and long flashes represent 10 heres a sample long, quick quick would be code 12. and there is often more than one so write them down and post em and we will see whats what.after they are done they will repeat so you double check. key on engine off. so when the light comes on shut off the engine but dont let the key go back too off. just turn the key back enough to kill the engine and then foward as far as it will stay by itself with out engauging the starter. i hope that makes sense.

[maxwedge]

Originally Posted by jd-autotech

ok retreiving the code and sharing that info is job # 1 -when then the light comes back on ethier have it scanned or poke a paper clip between the two top right terminals on your aldl connector under left side of dash and watch the check engine light flash and count the flashes,qiuck flashes represent 1 and long flashes represent 10 heres a sample long, quick quick would be code 12. and there is often more than one so write them down and post em and we will see whats what.after they are done they will repeat so you double check. key on engine off. so when the light comes on shut off the engine but dont let the key go back too off. just turn the key back enough to kill the engine and then foward as far as it will stay by itself with out engauging the starter. i hope that makes sense.

For everyones info here, the above procedure will not work on most 95 GM cars as this is the transitional year from obd1 to obd 11, a proper scanner with the appropriate adapter will be required to get the codes. BTW, welcome to AF, young man.

[jd-autotech]

yeah i thought some 95's were obd 1 and since the dealer couldnt retrieve history codes i figured it wasnt obd 2

[Supergumby]

The EGR code (on a 1995, it's probably code 77), is pretty common; there are three pintle valves that make up the EGR valve assembly, and the ECM checks the operation of the valve by turning all three of the valves on during extended zero throttle above (about) 50-55 MPH (like coasting down an interstate hill), and looking at intake manifold vacuum. If the vacuum remains high, the valve must not be working, so the ECM sets a code. However, 99 out of 100 times, the intake manifold passage has become clogged, removing the throttle body and EGR valve to clear it with solvent and a coat hanger fixes it.

[richtazz]

Welcome to AF sasmoshere. Max is correct that the paper clip trick won't work on 95 (and most 94) GM vehicles. As Supergumby suggested, try cleaning the passage leading to the EGR, and check it for kinks or cracks. IF your intake gaskets are starting to go (VERY common on the 3100's), it can cause a vacuum leak which will cause driveability problems and can cause EGR, MAP and oxygen sensor codes to come and go.

[sasmosphere]

Originally Posted by Supergumby

The EGR code (on a 1995, it's probably code 77), is pretty common; there are three pintle valves that make up the EGR valve assembly, and the ECM checks the operation of the valve by turning all three of the valves on during extended zero throttle above (about) 50-55 MPH (like coasting down an interstate hill), and looking at intake manifold vacuum. If the vacuum remains high, the valve must not be working, so the ECM sets a code. However, 99 out of 100 times, the intake manifold passage has become clogged, removing the throttle body and EGR valve to clear it with solvent and a coat hanger fixes it.

Supergumby you're right, it was code 77, you jogged my memory. I am going to do as you suggest & clean the passage to the intake manifold. It might take me a week to get around to that but I will let you know what the outcome is. Thanks guys for all your help!!