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P0300 helpp

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Old Sep 20, 2009 | 04:35 PM
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Default P0300 helpp

Ive been having this code pop up about once every couple of days for misfiring. I changed the plugs and wires and dont know what could be causing it. I have Corsa cat back.

And my car is running really hot compared to my friends vette, mines around 215, what could be causing it to run really hot?
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Old Sep 20, 2009 | 09:23 PM
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cats clogged? headgasket could cause both of those problems.....plugs look ok? no water in the oil???


you have plenty of coolant?
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Old Sep 20, 2009 | 10:15 PM
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Yeah no water in the oil, so not a head gasket and the plugs are good i just changed them maybe a 1000miles ago.

I just dont know what else to check?
I ordered a 160 thermo? Maybe its a messed up thermo, not sure thats why im turning to yall ha
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Old Sep 20, 2009 | 10:50 PM
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u need a tec2 to see what cylinders have the misfire. so- also could be a cloged injector. or a vacuum leak. .. but u have scan it first... and foremost.
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Old Sep 21, 2009 | 12:18 AM
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Alright i appreciate all the help guys, just tryin to figure out whats the dealll

But yeah i think im gonna take it to my tuner this week, so hopefully he can scan and see where the problem is, was just hoping to get a little more info from yall on what to expect!
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Old Sep 21, 2009 | 07:29 PM
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Its cylinders 5 and 7
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Old Sep 22, 2009 | 07:50 PM
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Originally Posted by Nasty99TA
Its cylinders 5 and 7
Probably something going on with the fuel injectors, try running some Techron through it. Might help.

Jimbo
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Old Sep 23, 2009 | 04:21 PM
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im having the same problem with my car but only on cylinder number 1 i looked for vacume leaks found none replaced the intire coil pack new plugs new injectors and new wires new o2 sensors no cats and no egr on my car and its still acting up if u figure it out please let me know what it was this is driving me nuts
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