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Impala misfire


javier60629
04-26-2014, 08:09 PM
I recently had my mechanic replace the head gasket on my 2002 chevy impala 3.4 v6, when I got it back I noticed a misfire, I had autozone diagnose it and it revealed a misfire on cyl.6, I replaced the spark plugs, wires, and coil pack and its still misfiring, can someone please help? Im running out of options!

Tech II
04-26-2014, 08:27 PM
Was a compression test done? Were both gaskets replaced, or just the 2-4-6 gasket?

If compression is ok on all cylinders, two possibilities....a vac leak at the intake gasket or an injector problem or leak at the injector o-ring..........

j cAT
04-27-2014, 03:38 PM
I recently had my mechanic replace the head gasket on my 2002 chevy impala 3.4 v6, when I got it back I noticed a misfire, I had autozone diagnose it and it revealed a misfire on cyl.6, I replaced the spark plugs, wires, and coil pack and its still misfiring, can someone please help? Im running out of options!

why don't you start from the beginning of your issues. like why the head gasket ?

so after the head gasket was replaced you then had the #6 miss or you always had the #6 miss ?
lets say after this head gasket was done you have this code , now you have the guy who did the head gasket check the compression on all those cylinders they should all be close. when the head gasket is replaced there surely is a lot that he could screw up.....

javier60629
04-29-2014, 07:37 AM
There was no misfire whatsoever before the gaskets where replaced, he replaced both gaskets and I have no idea if he did a pressure test on any of the cylinders, the reason it blew the gasket is over heating, I replaced the radiator,water pump,and thermostat. Also in case your wondering why I don't take it back to him, I moved to texas from Chicago so I cant contact him.

j cAT
04-30-2014, 08:05 AM
There was no misfire whatsoever before the gaskets where replaced, he replaced both gaskets and I have no idea if he did a pressure test on any of the cylinders, the reason it blew the gasket is over heating, I replaced the radiator,water pump,and thermostat. Also in case your wondering why I don't take it back to him, I moved to texas from Chicago so I cant contact him.

the head with the overheating can and most likely is distorted. the mechanic/repair shop should have had the head checked for these issues.

could also be a crack. compression test is needed if it has bad reading then this will need removal and checked out.

operating the vehicle with a miss will destroy the cat converters..

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