My grandfather gave me this car about a yr ago. No issues at all. Yesterday I was driving down a local street and the car started running rough. Check engine light came on....checked it and have a cylinder 6 misfire. I figure the plugs where due so no big deal. Pulled them and they where preaty beat up. So I changed all plugs and wires. Car is still misfiring. So I checked the coil with a light and all cylinders are firing good.
What should be next on my check list? Fuel injector? Should I pull the valve cover? I've read on here someone having one of the valve arm bolts back itself out.... really stumped here and would appreciate any help. Thanks

 

I'd suggest recheck plug wires for correct rotation i.e correct wire to correct plug, and tight installed i.e both ends snapped on to coil, and plug. Then I'd suggest injector cleaner in the tank. You say the plugs were pretty beat up, with 30K miles, do you know if they are original? I'd also look at the replacement spark plugs being what is called out for that engine.

 

I did one plug and wire at a time and checked them 10 times for being tight. Yea the plugs looked kinda beat up with 40k original plugs. Made sure the plugs where for the car and gapped correctly.

 

How did you check the coil with a light?

 

A ligght tester...one end goes on the coil the other on the wire or spark plug(witch I did both) and a light lights up every time there is a spark sent through it.

 

What did the plugs look like especially #6? Was there any oil fouling? Also what type air filter are you using, does it have an oil prefilter? Do you have any of the old plug wires? If so try one on #6. The only other is fuel treatment, have you done anything to the gas? It would be a VERY LONG SHOT, but it is possible you installed a bad plug, what brand plugs did you use?

 

The light buld does not tell you how much spark you have. It takes less voltage to light that bulb then to fire a spark plug. You need to see if the spark is blue or yellow.

 

yes spark plug did seem foul in #6 maybe from oil. but the guessing game is over...i took it to my mic today and there is no compression, thats right 0, non, nota, in cylinder 6. what the f$$k. well now should i rebuild or replace the engine....i would hate to put an engine in it with double the miles but i dont know whats going to be wrong with the engine once its opened up or let alone another cylinder failing once its rebuilt. Just can not believe the cars engine is done with only 40k. it has beeen sitting for a year or more but can that really do that much damage? ive been driving it for a year now....

 

thank good i didnt sell my turbo charged Subaru with 110,000 on it when i was given this car. id be kicking mysrlf in the ***

 

I had the misfire code on my 03 impala I changed the coil on #3 but it missed under load only .It ended up being control module I bought used one and it runs perfect . Dont run it long with it missing it will trash the cat converter, ask me how I know ? But no compression in the cylinder that is strange .Are you sure ?