ignition coil pack diagnosis?
Thread Starter
Heel & Toe
Joined: Aug 2001
Posts: 18
Likes: 0
From: libertyville illinois
ignition coil pack diagnosis?
Is there an easy way to test the coils individually? I have been experimenting w/ timing light as seen on previous post(s) - so far, maybe one suspect coil/wire... i don't have a scope.... I have atap but the misfires
are not enough to set codes and they seem to migrate. Also based on what i've heard the indicated # may not be the actual # etc...
I have changed all wires and plugs multiple times and as of yesterday there is still a definite miss somewhere, you can feel it at idle (i know this may not be an indication of a problem) but there are some really rough zones between 1000-2000 rpm etc... above 2500 all is smooth...
The service manual seems to only suggest checking for voltage to the coils etc. rather than testing the coils themselves if I was looking at the correct section...
I have tried spray down test...tests on wires w/ dmm ... injector fuses are of course fine. right now i am thinking there is an intermittent/weak coil...
any ideas on the coils or anything else appreciated...
jfc33
are not enough to set codes and they seem to migrate. Also based on what i've heard the indicated # may not be the actual # etc...
I have changed all wires and plugs multiple times and as of yesterday there is still a definite miss somewhere, you can feel it at idle (i know this may not be an indication of a problem) but there are some really rough zones between 1000-2000 rpm etc... above 2500 all is smooth...
The service manual seems to only suggest checking for voltage to the coils etc. rather than testing the coils themselves if I was looking at the correct section...
I have tried spray down test...tests on wires w/ dmm ... injector fuses are of course fine. right now i am thinking there is an intermittent/weak coil...
any ideas on the coils or anything else appreciated...
jfc33
Advanced
Joined: Mar 2003
Posts: 75
Likes: 1
From: Marshalls Creek PA
Re: ignition coil pack diagnosis? (jfc33)
Without a scope it's pretty hard to tell if your misfire is electrical in nature. Using a timing light on each wire one at a time will tell if the plug is getting secondary ignition and since you have replace plugs and wires it's safe to rule them out. I would try to check for a vacuum leak or the EGR opening to soon or not sealing.
Thread Starter
Heel & Toe
Joined: Aug 2001
Posts: 18
Likes: 0
From: libertyville illinois
Re: ignition coil pack diagnosis? (jfc33)
Thanks for the suggestions, i will look at them tonight...
What is the proper way to use propane or some other method to check for vacuum or intake leaks? Would I have to disconnect the throttle control etc?
As for the egr inpsection, should I inspect parts in addition to PCV type valves, the ones that can be checked with a finger to see if the snap back...?
If I can locate (hopefully borrow) a scope (general, not automotive) does anyone know or have experience if a wire by wire type of inspection would possibly show any differences. The cables and equipment for superposition of 8 waveforms etc will not be possible.
thanks,
jfc33
What is the proper way to use propane or some other method to check for vacuum or intake leaks? Would I have to disconnect the throttle control etc?
As for the egr inpsection, should I inspect parts in addition to PCV type valves, the ones that can be checked with a finger to see if the snap back...?
If I can locate (hopefully borrow) a scope (general, not automotive) does anyone know or have experience if a wire by wire type of inspection would possibly show any differences. The cables and equipment for superposition of 8 waveforms etc will not be possible.
thanks,
jfc33
