Ok I'll check it out tomorrow and see if I cant finally figure this thing out. Thanks again for all the help Greg!!

 

I think this fix is going to cost 50 cents.

 

I was thinking the same thing.

 

I will tear into it today and find out. That would be awesome if that's all it was. It would make sense to me "kind of",.....but since the test from the IDM harness is telling me that only the one bank is out then shouldn't that other bank run or at least buzz on a buzz test?? Or will the IDM not run either side if its not getting the correct readings from one??

Im just a little confused on the UVCH's and what will or will not happen if one comes apart.......??

 

That would be nice...

However, the IDM should still run the buzz test even with one bank unplugged.

 

Yeah this still concerns me!!

 

The engine can start with only one good bank but it's tough to get it to pop off. A warm engine will fire up no problem....a stone cold one will be a different story.

I am still learning specifics about the IDM but it sounds like there is a high side and low side as far as primary power is concerned. The high side is controlled by the IDM relay but the low side must have a fuse somewhere. My hope is that you will find a direct short to ground that popped a fuse and that is the reason why the IDM is not running the buzz test or syncing with the PCM. However, if that was the case then we should be seeing a code for IDM feedback signal (which you didn't report getting).

It may sound like I am sending you on a wild goose chase but I learned the hard way that it's best to verify the entire wiring harness before doing anything else. If your pulse width was in range and the buzz test worked then going under the valve cover would be the next thing to try. But we weren't that lucky so we took a different path by going straight to the IDM module. Besides, accessing that module isn't really that hard....sounds like a lot of work but it's easier than it sounds, especially if you have a 4WD truck or chassis cab truck.

Rich (Tugly) took the time to post the pin out for the under hood to engine harness (42 pin connector) so that is a real nice short cut to help folks figure out which valve cover to go after first. Although, I normally pull them both whenever I am helping someone wrench on their truck because spending 50 cents is more effective then only spending 25 cents in the long run.

At any rate....
Our primary goal right now is to get you to the point where you have a verified good wiring harness from the IDM all the way to the injectors. Once that is done then we can clear codes and try the buzz test again. With luck the IDM will sync and the engine will start.

 

Just one instance of this result is enough for me. I speculate they're both gone or flakey, and popping the VCs on both sides won't be a waste of time. I saw this issue on an Ex where vibration alone would change the test results.

Here is the whole story: [LINK]

 

Ok looks like were close. Pulled the 42 pin connector and got the same results:

Pin 22- OL
Pin 7-OL
Pin 19-11.2ohms
Pin 9-20.7ohms

Now that a little different from the IDM harness but I would expect that cause it now has less resistance from the IDM harness correct? But it still tells me that my problem is under the VC, hopefully I just need to dig up some quarters!!

 

Ok how the eff to you get the last bolt off the valve cover, the all the way at the firewall???

I got all the other bolts off easy and was able to move the VC up enough to fell the UVCH......what do you know, it was definitely loose I was able to push it on about a 1/4 inch or so. Im going to retest the 42 pin and see what it says. Even if it tests ok I obviously still need to get the VC's off.....so a good idea on getting that bolt off would be awesome!!

 

TEST RESULTS GOOD!!

Injectors:
#2-2.7ohms
#4-2.3ohms
#6-2.8ohms
#8-2.7ohms

 

I would agree with your thinking here....the readings should change as you move up the harness towards the injectors.

Cool. Don't forget to clear the codes before you rerun the buzz tests. I usually start up the engine with the valve covers off prior to putting everything back together.

 

I would agree with your thinking here....the readings should change as you move up the harness towards the injectors.

On my truck, a long 13mm socket and 3/8" ratchet will loosen that bolt easily enough. I then remove the socket from the ratchet and use the socket to screw out the bolt by hand. About half the time the bolt ends up on the driveway though...

Cool. Don't forget to clear the codes before you rerun the buzz tests. I usually start up the engine with the valve covers off prior to putting everything back together.

 

Ill make sure to clear the codes. Is it ok to start it with the intercooler tubes and intake off as well??

On the bolt I cant get a long 13 in there with any kind of an extension on it. Do you cut away that sound deadener/heat shield stuff??

 

Sounds like you guys nailed it!

Let's hope the IDM tests good when AE is reconnected.