Mechanics

CHEVY MULTIPLE MISFIRE

2006 Chevrolet Colorado

Engine Mechanical problem
2006 Chevy Colorado 4 cyl Two Wheel Drive Automatic 59000 miles

I had a misfiring problem and brought it to Autozone. They ran a diagnostics on it and said it was a number 1 misfire. I changed all the sparkplugs and the number 1 boot. It started running great and my gas mileage went up to where it should be. I drove it about 300 miles and it started running poorly again. I brought it back to Autozone and they ran another diagnostics on it and said it was a number 1 misfire again. I was told to switch the number 1 boot withthe number 3 boot to see if it changes from number 1 misfire to a number 3 misfire. If so it was a bad boot. I did that and brought it back to them for a third diagnostics check and now it is saying multiple random misfire. I was wondering what I can do to fix the problem myself. And maybe if it could be the box where all 4 wires run to. Please help. Thanks
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Gavin1029
June 16, 2010.




Random misfire is normally caused by vacuum leaks and bad fuel.

Rasmataz
Jun 16, 2010.
So what what I need to check for a vaccum leak?

Tiny
Gavin1029
Jun 16, 2010.
You can use a vacuum gauge, or listen to a hissing sound around the intake manifold and vacuum hoses.

Rasmataz
Jun 16, 2010.
So should I go ahead and change all four coils? Or maybe just the number 1 and 3 coil and see what happens. I know they are like 60 something dollars a piece.

Tiny
Gavin1029
Jun 16, 2010.
Check the no.1 cylinder compression and injector disregard the coils at this time till you rule out this two
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Rasmataz
Jun 16, 2010.
How would I go about checking num 1 cylinder compression and injector. I really don't know too much about engines. Just the simple things.

Tiny
Gavin1029
Jun 16, 2010.
You need to clean your throttle body, it is easy and cheap

Tiny
Byates
Jun 22, 2010.

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