UVCH Or IDM First??

JAP · Mar 16, 2012

http://www.facebook.com/#!/photo.php?v=2843596685392

Unfortunately, not everyone will be able to see this video. But anyone that can, would you think this probablem would be with the IDM? Or with UVCH's?

It's weird how sporadic it is, since it starts on one side, but then moves to another...

JAP · Mar 16, 2012

Can anyone see that?

Arisley · Mar 16, 2012

Nope, but if you put a scanner on it, won't it tell you more?

SDstroker · Mar 16, 2012

Does it run? I was told the IDM either works or it doesn't. I have the same problem and going to start checking the wiring.

JAP · Mar 16, 2012

Arisley said:
Nope, but if you put a scanner on it, won't it tell you more?

That video is of a buzz test.

I'm assuming, as said, that if the IDM is attempting to buzz them all, that my problem is downstream of the IDM. I just didn't know whether the IDM could get "dead spots" or not.

Arisley · Mar 16, 2012

Ahhh. I see (well I don't see, but I understand). Yeah, check where the wire bundle goes over the valve cover. Lots of problems there.

golfer · Mar 16, 2012

There isn't anything with 2, 4, 5, & 8 (the ones that didn't buzz) with regard to the IDM...

obviously...the IDM can fail in the common manner...entire bank 1, 3, 5, 7 and/or 2, 4, 6, 8...

and it can ALSO fail with regard to cyls 1,4,6,7 & 2, 3, 5, 8

but the pattern you have there...2-4-5-8 doesn't match up with an IDM being the issue...or the valve cover wiring...which makes me think it could the injectors...

how many miles are on this truck? any history on it?

JAP · Mar 16, 2012

300K. It's just an old XL Fleet truck. Was told by the PO that it may have low compression due to smoke and a hard start. I'm thinking the injectors not working could have definitely contributed.

Looks like maybe some rats took up home underneath the hood. I'm hoping that I can get away with harnesses and injectors if I have to.

If I find low compression on top of all this, the truck will be parted and scrapped.

PSDEng · Mar 17, 2012

The very first thought I had when I heard the video was the solenoids themselves, just because they didn't sound similar....at all. Does the software/device you're using complete the buzz test with any codes? If the pattern you're getting is 2,4,5,8 then I would start with the wiring harnesses since there's at least one cylinder in each group not buzzing. But I could be wrong....

JAP · Mar 17, 2012

The pattern is 12345678,

2,4,5, and 8 are dead. I'm going to look at it more today.

JAP · Mar 17, 2012

I got it running. No change in the buzz tests.

Chvyrkr · Mar 17, 2012

SDstroker said:
Does it run? I was told the IDM either works or it doesn't. I have the same problem and going to start checking the wiring.

I pulled an IDM out of a crappy runnin truck that was half full of water. Granted, the truck wasn't running well, but it was running. Popped IDM codes on the buzz test, while buzzing all 8 injectors. New IDM and it ran clean and stopped popping codes.

FWIW, I've chased more issues in the wiring between the IDM/PCM and the big valve cover plug, than I've had with UVCH's or IDM's.

SDstroker · Mar 20, 2012

JAP said:
I got it running. No change in the buzz tests.

Same cylinders still buzz like crap?

JAP · Mar 20, 2012

Yeah. As of now. I'm considering just changing the UVCH out as well as the valve cover gaskets. I agree with golfer as far as it seeming like the injectors, but the harnesses probably need to be changed anyway.
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