97 Grand Am 2.4L Multiple misfire


Ronbowtie
05-18-2005, 08:37 PM
While having trouble with my GA I drove it to the closest Auto Zone and found that it has had mutiple cyl. misfire. While at a idle it runs very bad and the exhaust sounds like pop pop pop.I have taken the IAC out and cleaned it, cleaned the throttle body, then tried to see if that helped . It didn't. While driving it down the road it runs fine, lots of power and no misses, but when it idles as I said Auto Zone says it has multple misfires. Can someone give a clue as to where to start to find the problem?

Hoags
05-18-2005, 09:42 PM
You may have a coil pack going bad, I had one act like that and then it finally went, the car began to run rough even at higher RPM's. You may also have a crack in the ignition housing ( I had to replace mine at about 95,000 miles.) Yet another item could be a bad ignition module. Mine went at 115,000 miles but it went quick...from running OK to running like crap. These are a few of the items that gave me a rough running condition. You may also have a plug/wire issue going on as well.

I hope this helps,

Welcome to the forum.

Ridenour
05-19-2005, 11:01 AM
^ ^ I agree with everything dan said, but also one more possible culprit might be a bad o2 sensor.

Ronbowtie
05-19-2005, 06:36 PM
While having trouble with my GA I drove it to the closest Auto Zone and found that it has had mutiple cyl. misfire. While at a idle it runs very bad and the exhaust sounds like pop pop pop.I have taken the IAC out and cleaned it, cleaned the throttle body, then tried to see if that helped . It didn't. While driving it down the road it runs fine, lots of power and no misses, but when it idles as I said Auto Zone says it has multple misfires. Can someone give a clue as to where to start to find the problem?



I made a mistake on the year model it is a 1996, but same goes. Got a scanner today and found that the codes are po172,po300,po302, and po108...While scanning it many times I find that when the po302 code comes up the fan starts to run at that exact time also....wondering getting these codes could I have a blown head gasket as there is a pop pop pop in the exhaust the intire time the cars is running. When I got the po302 code I changed the # 2 plug and that code has not come back up.And neither has the po108 map code.Also when the po300 code comes up the valves are pinging like crazy and the engine knocks bad. Sorry but alot of help is needed here...........but thanks for all the help

jkpacyga
05-19-2005, 07:17 PM
I made a mistake on the year model it is a 1996, but same goes. Got a scanner today and found that the codes are po172,po300,po302, and po108...While scanning it many times I find that when the po302 code comes up the fan starts to run at that exact time also....wondering getting these codes could I have a blown head gasket as there is a pop pop pop in the exhaust the intire time the cars is running. When I got the po302 code I changed the # 2 plug and that code has not come back up.And neither has the po108 map code.Also when the po300 code comes up the valves are pinging like crazy and the engine knocks bad. Sorry but alot of help is needed here...........but thanks for all the help

you might have a bad fuel injector. i just got one of mine replaced ysterday in a 2002 pontiac.

Ridenour
05-19-2005, 09:23 PM
you might have a bad fuel injector. i just got one of mine replaced ysterday in a 2002 pontiac.

Yeh - one of yours could be clogged or leaking also. A can of really good injector cleaner (if I remember right, Lucas is really concentrated) might do it, or if you really wanna do it right, have a professional injector / fuel system purge - roughly 120 $ at your local shop. That may solve it.

Hoags
05-19-2005, 09:47 PM
Check your local Midas shop, they cleaned my injectors for $60.00, Made a big difference.

faboloustw911
05-20-2005, 10:06 AM
well my 95 did the same exact thing....changed the coil cover, spark plugs and plug boots...and it was fine...but if it goes too long unfixed and running it will destroy the misfiring cyliders...coil cover cost me 30 bucks plus the cost of the plug boots and plugs themselves...try changing those and see what happens.

-K.C.

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