Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Yes they can, it looks like a few monitors have not ran
All of these monitors can affect misfires.
The reason they set is because the PCM is trying to run a programmed routine and it fails because it "sees" something it doesn't like.
Clearing Codes repeatedly will also show these monitors from setting, because the right conditions have not been met to run them.
A scan tool that graphs live data here would be very beneficial to see what those pre and post CAT sensor are doing.
The Evap monitor has not ran either, the big thing here is to make sure the purge valve isn't leaking.
Not sure if your Innova is capable of graphing, but knowing what the fuel trims at all engine loads is super beneficial.
If your fuel trims are Positive Percent at idle but improve closer to Zero as the RPM is raised is indicative of a vacuum leak, PCV system, Intake, Purge valve, brake booster etc.
Scanner Danner has everything you need to learn how things work and how to do proper testing, He is worth every penny!!!
I have a question about coil packs, how do you test them ?
Was reading on a forum that you use a ohm meter to check continuity ( plug 1 to 6 ) etc
But their must be a better way to test it ?
I am working on an 2003 jeep tj 4.0L, has a misfire on #1 when it warms up .
What I would do is remove the coil pack, ground each coil and check for spark when warm and start misfiring. If you don't get spark in cylinder #1, the coil pack has to be changed or if possible the coil replaced. If you get spark, most lightly not, I would unplug the injector and check for injector pulse and ohm the injector out to check for continuity. There are 3 drivers for the 6 coils. A wiring problem would most likely cause two coils not to contribute. I would also do a cranking compression sound test or do an actual compression test and check for intake manifold leak when cold.
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Did some checking wires, got all the grounds replaced, still got a misfire,
checked continuity on the injector wire ( the ground from PCM ) they test ok.
( unplugged harness from pcm and tested to injector plug )
backed probed the power wire at injector ( engine running ) and got this....
the power runs at 13.7 V and every few seconds it dropped to anywhere from 0.5 V to 5.4 V.
tried to post a video of the multi-meter, but it failed .
the pmc plug lay out i have is not showing the power feed for the injectors ? or they call it something different ?
backed probed the power wire at injector ( engine running ) and got this....
the power runs at 13.7 V and every few seconds it dropped to anywhere from 0.5 V to 5.4 V.
That is not good, if you backprobed the injector power feed, and were on battery negative with your meter, the voltage should read charging system voltage and not drop out.
If you them move from the battery Neg post to the Positive post, whilst backprobing the power feed, you have less than 150mV.
These ASD relay feeds all of this, the contacts might be failing.
Thanks for the info.
Yes the ground from meter was on battery ground.
Changed the ASD relay ( had a spare relay ) made no change. Was sure when I had checked the power wire to coil pack their was no fluctuation in power, but will check it again to be sure. The coil pack and injectors both get power through the ASD relay ?
Looking like a problem in the wiring , checked 4 of the 6 injectors power feeds with same results.
Do you have a diagram for the two big plugs on the fire wall at the back of the engine, thinking the injector wire goes into one of them,
this will be another spot to check for power drop.
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