Hi guys.

I have an 94 Corsica that has just started idling pretty rough. This vehicle is my girlfriend's, so I don't have much experience with it. I believe I saw 149,000 miles on the odometer today, it is also an automatic. I think that is is a 3.1? I know that it is a a V6 for sure.

She has told me that the vehicle was running fine yesterday, but today it has started idling really rough, and she thinks that it is going to blow up.

Of course, after I got off work, I decided to take it around the block to see what it was doing. I noticed that when pulling up to a stop sign, or a red light, the idle gets low, and seems like it wants to die. If you put it in neutral, or park, it idles fine. Also, when starting off accelerating, it seems like the transmission shifts a little bit harder than you think it would into second gear.

She has told me that she has seen the Check Engine Light flash a couple of times, but I am not able to duplicate this. Since it is an OBD1 vehicle, I cannot figure out how to read them with a paper clip. Not even sure if that works on these vehicles, but nevertheless, I failed.

Do you guys think that this is the fuel filter that may be clogged? Plugs and wires? I'm sure they're old. How about the fuel pressure regulator? Not sure if they're equipped with one or not either.

Any information is greatly appreciated. Thank you.

-Nathan.

 

stop at autozone or a similar place to see if they will scan for codes. There may be a history code set in there and will give you a good place to start

 

Already tried Auto Zone, they were unable to scan because their scanner is an OBDII reader. Thanks for the information anyway.

 

Here is an update to my situation.

Doesn't seem to make that much of a difference, but it has gotten to where it doesn't stall while driving..

Changed fuel filter, spark plugs. I haven't gotten to change the spark plug wires yet, even though I don't think they are at fault. I cleaned what I think is the MAF, the IAT, or I thinkGM calls it the MAT sensor, and have some injector cleaner running through it.

As it turns out, whilst doing some research on this vehicle, I came across this website that was telling me the reason why I couldn't read the codes..

Apparently in '94, GM decided to put parts of OBDI and OBDII together. Albeit they are not using the name (OBD 1.5) This is what it turns out to be. (Where OBDI has a 12 pin connector with pins 5 and 6 having a pin in them. OBD 1.5 has a pin in holes 6 and 12. You need a special tool to read it.)

Which brings me to my next question. Anyone know of a scanner that is able to read these, and read later models as well? I'm lost on this vehicle, and just throwing parts at the problems without the codes.

Thanks for any information...

-Nathan