Alright, for the past few weeks the truck has been a little "doggish" when I set the PM on the higher settings (5+). I passed it off as my just being so used to the kick in the rear. Today I noticed that it wasn't kicking down to the next gear when I mashed the skinny guy to the floor around 35-40mph. Usually it will drop, pull to about 2500RPM and then grab 3rd lock up and put me in the back seat. I contemplated the problem and came up with only two things; 1) VP saying goodbye (it has less than 15K and I know, I know, the FP gauge is coming at the end of this month.) or 2) TV cable to the transmission, will be looked at tomorrow as I have to use an ASE shop to change trans fluid and filter to maintain my ATS warranty.

So I run up to Advance Auto Parts since they are the closest to home. They won't let me touch there little OBDII scanner to pull the codes. They have to do it. After the third attempt and same result (Operating System Error), I said my thank you and smoked them as I left the lot for the dealer. Hah, I get to the dealer and the service writer points me to the cabinet where the DRB's are and lets me loose. I pull the DTC's and nothing! Nada, Zip, Zilch!!! Not a single code in 6716 starts since last reset.

So do any of our high horsepower residents have any ideas? Could the VP still be laying down even though I didn't get the dreaded P0216? I still pour smoke, get crazy high EGT's with the stock charger, and of course I'm overboosting to the tune of about 46PSI. Any thoughts are greatly appreciated!!!

 

Your excessive boost is costing you HP. Drop it down to 35 psi and you'll actually have more air getting into the engine.

Yes, your VP can be dying without throwing a code. It's rare, but it's happened.

Your killing your truck with the torch hot EGT and overboost. Keep playing like this and you will have an expensive bill-- maybe sooner than you think.

jlh

 

If you are blowing out the fire from overboost, your EGT's will be colder than normal, and then the boost will drop out like a rock and you will end up down about 19 PSI and running like a slug.

Since you are still running high EGT's, and I assume you mean something in the 1,375 degree F range at the boost you list, I would do a compression test. Either you have burned a piston land down into the ring groove, or you have lifted the head. By my shop dyno table, 46 PSI would equate to 506 horses at 1,250 degrees F, and to 618 horses at 1,375 degrees. Either of those ranges will mean that your head bolts are stretched and the head gasket gone unless you have studs, fire rings, and a solid copper headgasket.

Frankly, I do not understand how you can flow that much fuel through a stock VP44 without a resulting delivery valve failure.

 

Your overboost is superheating your air charge and causing it to expand instead of compress. turn your boost down to within specs of the charger (anywhere between 32 and 36. Plus that much boost and you could explode your charger.

 

What are 360 Bosch injectors?