Stumped! 1997 Pontiac Grand am Lopes at idle.

Asked by Des1006 Jan 31, 2012 at 05:54 PM about the 1997 Pontiac Grand Am 4 Dr SE Sedan

Question type: Maintenance & Repair

I have a 1997 pontiac grand am that I am trying to fix for a friend. Started out with a coolent leak. Replaced inake gaskets but, that was not the problem. Turned out to be timing cover gasket. Just got it all back together and now it Lopes at idle. If you rev it, it goes away. I have an equus 3160 and I plugged it in and got code po300. Random cylinder misfire. When you look at the freeze frame data it looks ok (not that I understand what I'm looking at) but, the RPM said it was 1711 rpm. I then did the live data and the RPM said the same thing plus it didn't move when I reved the engine. I'm thinking the crank position sensor but, I'd like someone elses thoughts before I do it. I have also replaced the cam position sensor as the wires were skinned. Any help would be appreciated.

Des1006 answered 12 years ago

I FOUND IT! Turns out that the Haynes manual tells you to torque the air plenum to 18 in/lbs. It's not enough. Re torqued mine to 35 and problem went away! Life it good!

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JoshCampana1 answered 12 years ago

My '97 was doing the same thing but when I took mine to the shop they replaced 2 coils, a couple spark plugs and some bad wires and she was running better than I have ever seen her.

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