Misfire

rick · Post by **rick** » Tue Mar 11, 2008 10:52 pm

I just replace the lower intake gaskets on my wife’s 2000 Blazer. The intake had a coolant leak. When I put in back together it developed a misfire. Rough idle is intermittent, upon hard acceleration it backfires, slow acceleration its fine. Codes came back as misfire in cylinder 6. I am going to change the plug and wire. I believe the distributor is in right. I had a hard time putting it back in, at top dead on the balancer the distributor never really pointed at #1. I check it with my CC and it appeared to be in the right position. I cleaned the throttle body and sprayed the AIC motor with carb cleaner(?). All wire connections are fine and so are the vacuum lines. It ran perfect before I took it apart. I plan on taking it in to the shop if I cannot diagnosis it first. Any help would be appreciated.

BADs Crew · Post by **BADs Crew** » Wed Mar 12, 2008 5:37 pm

I would take a close look at the cap and rotor. Make sure it is not cracked/worn and see that both are seated properly. Are the plug wires new? I had our Blazer at the dealer 3 times because it was running rough before I gave up on them and tackled it myself. I changed the plug wires and the problem was solved.

rick · Post by **rick** » Thu Mar 13, 2008 3:18 pm

Took it to the shop and had a tech look at it. Found out the problems. Apparently when I was moving the wiring harness to replace the intake gasket the crank sensor harness was dry and brittle from oil leaking on it, so when I moved the harness it damaged it, so they put a new pigtail and crank sensor on it. The shop also replaced the cap and rotor and #6 plug. The also told me than number 6 has a slight lean mixture to it, the new gasket may not be seated correctly or the injector is going bad and it I wanted they could run more test on it. It does run fine for now.