Picked up my "new" project car lastnight 134k on the clock, but taken care of.


Driving her home, she gave me a taste of her personality...or just what she thinks of me Anyways, She runs rough, was bucking down the road, and was hard starting once I got her home in the driveway. The car runs cool and temp was fine with the A/C on(to confirm the fan kicked on) too.

Read quite a few threads so far on problems with 2.8/3.1 cars...When I popped the hood at the gas station to put some 93 in i noticed 2 things.





1-Exhaust gases coming out of the EGR valve area. Not sure where exactly but right in that area.

I assume its the original EGR valve and the whole thing has got complete carbon build up. Im thinking bout just getting an EGR valve or 2 from the junkyard and swapping them. The only other thing that I was debating it being was something to do with the fuel pressure regulator. Possible allowing to much fuel to pass.

I noticed if i started the car up in the driveway, in park or neutral (no load on the engine) it idled better, once I put it in gear however it's idle manorisms changed. This kinda has me believing the bucking and running rough isn't the EGR valve. As i undertand the EGR, if it were completely junk wouldn't allow the engine to even idle in park any different than in gear. Possible IAC in need or cleaning/replacement?

Im also thinking about taking the EGR off (leaving the harness connected), blocking it off with a plate to see if this changes things.



2-she seems to put out some smoke. Some what grey/white.

I know white smoke= head gasets, i kept my eye on the oil pressure. Seemed fairly consistent. Also she only smoked for the first few minutes, once the car was warmed up she seemed to settle down. Still bucking and runnin rough but stopped smoking. Im assuming its worn valve guides + seals. The injectors, distributor, cap, rotor, plugs & wires, water pump and thermostat were all recently replaced.


I just want to get the 3.1 runnin good and solid like it did for the previous owner (before his mechanic got to her) til I get my 700-R4 built to handle the 357 I've got on my engine stand.








Any thoughts or ideas are much appreciated!

 

i would check the coolant level and oil color if its got white smoke.

 

sure seems like its an EGR related problem. Got home today after playin Joe Air Force and sling autoparts for AZ, went out to the car to see if there were ANY stored codes to be pulled even though the SES light isn't on...got 5!!!

Codes: 13, 33, 34, 35 & 45!

Check them against my '91 Pontiac Firebird GM tech manual. 2 are Oxygen sensor related, 2 are MAP sensor related and the third is IAC related. This coming I get back I plan on doing a ...

*complete engine flush with Seafoam,
*oil + filter & PCV valve change with a bottle of Restore,
*flush the cooling system,
*replaced the O2 sensors,
*install my MAP sensor with a spare i have,
*change the plugs,


Is this normal, do OBD I compu store codes/faults but sometimes "fail" to illuminate to let you know theres a problem?? The computer flashed "12" 3 times in series like it should indicating that the PCM was okay...????
*clean the throttle body and IAC

 

replaceing the map will definatly help. mine died a few weeks ago. had 2 codes for it. hi and low voltage.

code 12 is the handshake code. it lets you know the computer is ok.

i would definatly clean up the iac first. it could be bad cleaning the passages would help tons though.

for the o2 sensor sounds like it might need replaced and check the wireing on it to see if it could be disconnnected or have a broken wire.

as for the ses light it could be burnt out.

sound like your on the right track though. good luck.

 

I appreciate the response enswrob, but the SES light NOT staying illuminated even though I pulled stored codes confuses. With the Light out the computer is saying the problem(s) been fixed, however if you heard the car run you;d know damn well other wise...