jimbo0004

1992 pontiac grand am
4 cyl, 2.3 liter, D type engine
automatic, 80K miles

Last week I jumped in my car to go to work. When I started it, it ran real rough at idle when in park, but I didn't think anything of it because it had been sitting for 4 or 5 days in cold weather.

As I started driving, it got progressively worse. It kept stalling when I took my foot off of the gas. In order to prevent it from stalling, I would slam the pedal to the floor and the engine would revv real high, but the car would only respond about 40-50%. On the highway, I couldn't get it past 55mph.

I also heard some rattling coming from what sounded like the bottom of the car. Was able to make it home, but it now won't start. I probably drained the battery from trying to start it too many times.

Also heard a sputtering noise when giving it gas. It kind of sounded like a helicopter. The sound gave me the feeling like the exhaust was fighting to get out.

does anyone have any suggestions? thanks in advance.

Matts3100

I would check to see if your converter was plugged. And driving it with the converter plugged may have ruined something else that wont allow you car to start

Ridenour

Definnately sounds like a plugged cat for sure
-get it replaced (or gutted for the matter) and you shouldn't have anymore problems.

jimbo0004

I was able to get the car started again today. Once it started, it ran very rough. The exhaust seemed to be coming out fine except it kept sputtering since the engine was struggling to stay running. At idle, the engine was shaking vigorously. It ran fine for about 5 minutes until I gave it a little gas. Once I did, it revved up...sounded like a gokart engine. But then as it came back down to idle it would stall.

Today I checked for blockages in the exhaust and was not able to find any. Any ideas? thanks.

P.S. 3 more main questions...
How do I check to see if a catalytic converter is bad?
How do I check to see if the housing around the plugs are bad?
Does anyone know how to read and interpret codes on this car?

Chazman

You will have to remove the cat to check it - they just plug up solid.

Which housing ? the plug boots ? Coil pack ?

A Haynes or Chilton manual will help you interpret the codes.

jimbo0004

chazman...I was referring to the coil pack. They're expensive so I didn't want to have to buy a new one just to test to see if it's bad. thanks

Chazman

There is a test section in the Haynes manual - its a little long for a one finger typer to reproduce here.

It is called "Integrated Direct Ignition (IDI)"

I found it in Chapter five.

jimbo0004

I removed the housing and coils. I took a good look at the housing and it looked OK to my knowledge although I wasn't sure what you meant by looking for minature burn holes, or arcing at the insulators. I didn't see any burn marks or abnormal markings anywhere. When at the auto parts store this morning, I was reluctant to buy a new housing until I know that it's bad (it costs $60). I did buy a new coil though ($30), and tested it in the car with one of the old coils. It didn't seem to work and when I retested it with the other coil, it didn't work either. I'm not sure what to do next.

The car runs at idle right now, although very rough. It stays running in idle or when giving it gas, but then stalls when it slows back down. Sometimes I can keep it going if I gradually ease my foot off the pedal and play with it when I hear the engine start to die.

I noticed something else interesting today. While it was idling, I started to pull some of the little vacuum hoses off of the front of the engine. One of the hoses that I pulled ran to a sensor on top. When I pulled it off, the engine would respond by running normal for a second or two, and then go back to running rough again. I noticed that the hoses are extremely cracked. Could escaping air from the hoses be a possible cause of the problem? If not, what would you suggest to try next.

Chazman

Most definatly !!!

Vacuum leaks can cause nightmares !!!

I would check or just replace all vacuum lines - their cheap.

Could very well solve your problems.