missfire help
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Teching In
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Join Date: May 2015
Location: Midwest City OK
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missfire help
Ok, I just installed a set of Speed Engineering shorty's on my 03 Sierra 4.8L. Right after installation my engine light came on and I had a rough idle. Come to find out I broke the coolant temp sender and I had 2 plug wires that were jumping fire #5 and #8. I replaced the coolant sender and all plug wires. of course the P0118 went away but now there is a P0300 for a random missfire.
I hooked up a tech II and see that #4 and 5 are the problem cylinders. I have checked and double checked that I got all of the wires on good and can not see any fire jumping.
The last time I had a randome missfire it was my fuel pressure regulator. Anyone think that might be the problem again or should I be looking somewhere else?
I hooked up a tech II and see that #4 and 5 are the problem cylinders. I have checked and double checked that I got all of the wires on good and can not see any fire jumping.
The last time I had a randome missfire it was my fuel pressure regulator. Anyone think that might be the problem again or should I be looking somewhere else?