2004 Chevy Trailblazer LS misfire
I have a 2004 Chevy Trailblazer LS 6 cylinder 4.2 with 138k miles on it that developed a misfire in cylinder #4.
I thoroughly cleaned the throttle body....still a misfire.
I changed all plugs, fuel filter, air filter, checked all coils...still a misfire.
I swapped the plug & coil from #4 to other cylinders & had it re-tested...still misfire in #4.
Used fuel injector cleaner...still misfire in #4.
After all of these steps...I did a computer re-set by disconnecting the battery terminals & using my jumper cables to connect the cables for 30-45 minutes.
Am I right in thinking the problem HAS to be either electrical or compression? What should my next step be on a budget?
Thanks in advance!
physically check for spark (see FAQ)