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Unread 07-22-2014, 06:07 AM   #31
86cj74.2L
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Quote:
Originally Posted by outofrng623
Two round trip drives this week that would normally trigger the p0420...Did not. The only differences are, I put in a new battery (yes I have disconnected and reset prior to changing), so its not the reset, maybe the voltage...and I disconnected my obd2 scanner.
So you hooked the ground strap back up too?

Plus you always has good highway milage. Correct? Just crapy city milage and the P0420 code at times with a new CAT.

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Unread 07-22-2014, 07:39 AM   #32
outofrng623
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Didn't touch the strap yet.
Highway is usually pretty good and the code throws cause that's part of the test parameter to test it. 40-50 mph x rpms x amount of time etc.
Without a doubt both of those trips, round trip, would've set the code 4 times after resetting cel each leg of the trip.
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Unread 09-08-2014, 05:04 PM   #33
outofrng623
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I am sure you (86) have seen it already, but for everyone else, ground strap was replaced again, no change. Injector leakdown and compression test done, both pass with flying colors. Smoke test also done, no leaks...
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Unread 09-08-2014, 05:28 PM   #34
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Quote:
Originally Posted by outofrng623 View Post
I am sure you (86) have seen it already, but for everyone else, ground strap was replaced again, no change. Injector leakdown and compression test done, both pass with flying colors. Smoke test also done, no leaks...
Reflash yet?
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Unread 09-08-2014, 07:48 PM   #35
outofrng623
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The two tests were done today, so...my reflash debate is in my head. Do I spend 125 to reflash and take the chance on the pcm actually being good or do I find a refurb ecm?
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Unread 09-08-2014, 08:43 PM   #36
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Quote:
Originally Posted by outofrng623 View Post
The two tests were done today, so...my reflash debate is in my head. Do I spend 125 to reflash and take the chance on the pcm actually being good or do I find a refurb ecm?
Hmmmm good point. I would imagine if the pcm was bad more would be wrong from what I've read. But you never know. Same goes for if u get a new pcm, will it be updated? I'd hope.
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Unread 09-08-2014, 09:12 PM   #37
SleepyFloyd
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A bit late on the topic but a good way to test coils is to just shoot some water on them with a spray gun during idle. If it bucks and miss-fires then the insulation is flawed and you're arcing.
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