What codes show up if you rescan after clearing without starting the engine?

 

Only ones are P1000 and P0603. Guess I’ll be taking the valve cover off again to check cylinder 6 since that injector is very clearly off. Other than that I’m just stuck.

 

Have you tried checking PERDEL's yet? I'm not sure how helpful it would be but I get the feeling we're entering the grasping at straws territory.

 

I don’t think I have the PERDELs function on the Android ForScan app I’m using. I’ll investigate tomorrow. Thanks

 

I don't remember what it's actually listed as, because it isn't available for the E99's best I can figure, but I do think it's there for the L99 and up.

 

I wonder if #8 injector is bleeding off HPOP oil internally or something. You've done everything else but the injectors.

 

Well, I tried to redo the injector connectors again, but still have the same problems. The truck runs and drives but clearly at least one cylinder is not firing (6 from the data and buzz test). My last resort is to reinstall the OEM engine wiring harness to remove the new one as a potential problem. Too hot and humid to get it done today.

I did find and try to gather data on the PERDELs but nothing ever showed up in the table or graph.

 

I use forscan with android to monitor perdels, if I'm not mistaken the truck needs to be warm and at idle? Someone more knowledgeable about that can chime in. Have you tried oming out the wires from the VC connectors all the way to the IDM?

 

Truck was warm and the reader appeared to be transmitting data throughout the test but nothing appeared on the graph or the tables when I looked. The entries were there for all of the cylinders but they all showed 100%.

 

Swapped out the wiring harness for the OEM and that helped the way it ran but the codes are the same. Cylinder 6 still showing injector issues, but the buzz test sounded normal. I drove it around and off throttle on the ‘normal’ tune, the motor is skipping and jumping but not dying. On throttle it’s strong and sounds normal. No stumbling on throttle on all the tunes. When on the ‘stock’ tune or the towing tune, it’s way smoother off throttle, almost enough to think it’s running correctly.

So what now? I’m out of ideas and need my truck!

 

I forget have you checked the idle validation switch PID or the APP yet?

 

Sorry, I’m not familiar with idle validation. Which is that?

 

It's pretty much the equivalent of a momentary push button that tell the PCM you're on the throttle. Just an on or off signal sent to the PCM but it can throw a wrench in the works if it the wrong signal. It's available to view with Forscan.

 

So I played around with the DP Tunes today. When driving around in ‘stock’ mode or my towing mode, it’s very difficult to tell anything is wrong, on or off throttle. It runs just about perfectly. Switch it to my normal everyday mode (+80 hp, economy) and all hell breaks loose. That’s when off throttle it’s stumbling and sounds terrible. Plus throttle response is almost like a switch - very abrupt either way - on that tune.

I am trying to get it in my local diesel shop next week. Any other suggestions for them to check?

 

Maybe the tune is to blame if it runs "perfectly" in stock mode?