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The car is a 09 Gt with about 120000 miles. On my way to work, my check engine light came on , so once I made it to work I used my scanner to see wat code popped and it was P0301 (missfire first cylinder). So later that day I changed out all my plugs with new wires and also #1 cylinder coil pack. Still running like garbage. Wat other things should I T/S for. Could it be a vacuum leak, cause it is running rich and can smell fuel and see white smoke coming from exhaust, or maybe fuel injectors. Any help and suggestions are greatly appreciate, this is my only vehicle and I need it for work! Thanks
 

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The car is a 09 Gt with about 120000 miles. On my way to work, my check engine light came on , so once I made it to work I used my scanner to see wat code popped and it was P0301 (missfire first cylinder). So later that day I changed out all my plugs with new wires and also #1 cylinder coil pack. Still running like garbage. Wat other things should I T/S for. Could it be a vacuum leak, cause it is running rich and can smell fuel and see white smoke coming from exhaust, or maybe fuel injectors. Any help and suggestions are greatly appreciate, this is my only vehicle and I need it for work! Thanks
Intake manifold gaskets? Specifically cylinder 1?
 

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Could be numerous things such as a vacuum leak, faulty fuel injector, bad wiring harness (fuel injector/coil pack), or a failed lifter. Basically, it a process of elimination and does the vehicle still have the original dod lifters?
 

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Yes it does have the original lifters and the have been deactivated, I have white smoke coming out the back when I hit the gas. Could it be a head gasket, I really don't want to take the heads off, car is not over heating , or should I go ahead and change the intake manifold gaskets, once again it is only saying cylinder 1 misfire.
 

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Have yet to see a vehicle with a failed head gasket that doesn't overheat, but that's not to say such cannot occur. Check the oil dipstick for signs of water contamination i.e. excessive moisture or a milky looking substance. Bear in mind, the car could still have a head gasket failure and the oil looks perfectly fine. Alternatively, simply monitor the coolant reservoir level on a regular basis or take it to an automotive establishment that can perform a "block" test.
 
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