Chevrolet Malibu Forums banner
Cancel

Engine runs rough, in gear, at stop

16573 Views 7 Replies 3 Participants Last post by  FiremanDave, 
F
I have a 1997 Malibu with a 3.1L engine. I just replaced the intake manifold gasket, and now after the engine heats up, it will idle rough while the car is in drive at a stop light or sign. If I slip the transmission into neutral, it runs just fine. There is only one code, but it's for the catalytic converter, which is scheduled to be replaced within a week. It almost feels like there's a detonation when I'm idling at a stop. Any suggestions?

I work for a gas station with an attached garage, and they could only suggest that the torque converter clutch or associated solenoid could be the issue.

Thanks
Save
Like
Status
Not open for further replies.
1 - 4 of 8 Posts
F
It has ~176,000 miles, plugs, wires, coil packs, ignition control module and intake manifold gasket replaced 2,000 miles ago. No, they didn't inspect the vehicle, I simply described the symptoms as I have here. I checked the compression after changing the intake manifold gasket and they were all in tolerance. The plugs are Autolite platinums, 8mm silicone wires. The only DTC is P0420, "Catalyst System Efficiency Below Threshold (Bank 1)". Other than that, the car runs like a champ.

Beyond 12,000 miles ago, I don't know what kind of abuse the car may have suffered, I purchased it used.
Save
Like
F
Fair enough. Thanks for the suggestion. The only reason I was asking is it doesn't run rough at all unless it's in drive or reverse and the car is stopped. I would think a cat getting plugged would cause hesitation throughout the acceleration curve. But IANAM.
Save
Like
F
chevyguy8893: I understand completely. The question was more for my own clarification than anything.

Starship: I'll do that the next time I'm at work. My OBDII scanner needs an update to view freeze frame data from my car and I lost my cable. >_< I'll check the ATF today and have the mechanics check my fuel pressure when I go back to work. Thanks for the suggestions.
Save
Like
1 - 4 of 8 Posts
Status
Not open for further replies.
Chevrolet Malibu Forums
Chevy Malibu Forum is the best place for owners of the sedan to connect with the community and discuss MPG, mods, and more. Join now!
Full Forum Listing
Explore Our Forums
Gen 7 Problems/Service Issues/Troubleshooting Gen 7 General Discussion Gen 5 & 6 Problems/Service Issues/Troubleshooting Gen 7 Modifications Gen 8 Problems/Service Issues/Troubleshooting
Top