Engine/Transmission (1998.5 - 2002) Confusion runs amok--PM 3 EGT woes...

[voice of reason]

Howdy members...



So I have this nifty little box, known to y'all as a TST PM3. Great little bugger, love the remote/gauges/idiot-proofing features. Only problems are...



---EGTS are ***waaaay*** outta hand (will reach 1500+ if I let it)

---Boost levels too high? (38 PSI lev 6/stg 2; 45 PSI lev 9/stg 3)

---Grenaded one VP44 (sounded uuuuugly) while... . er, "testing"

---FP at 'test' fitting *drops* as throttle is added (checked on road)



I'm a veteran auto/truck tech, and have a thorough understanding of this stuff--mostly, anyway.



Mods are as follows:

PM3; 4" Turbo --> tail exhaust w/free flow muff; K&N filter on turbo inlet; ATS 3-lok TC



Truck is due for LOF and FF, but not crazy overdue or anything. At first, I resigned that the PM3 box was just more than my stock combo could handle, but thought differently when Mark Chapple responded with silence upon hearing of my VP44's demise with no other bombs. Now (it's been a couple years since the VP44), I am starting to wonder if overboost is a factor..... thoughts? (and no, no codes have ever been set)



Any help is greatly appreciated--and please know that I cannot check this daily, as I drive a (bigger) truck for a living.



(Take humor in knowing that my 52K GVW 2003 IH 7400 4x6 has the "big" engine--the DT530 (yes, cid), rated at 275hp/800tq. I'd bet my little CTD 360 will match or beat it... . muhahaha!)



Thanks in advance!!!



trent...

 

[Briar Hopper]

Trent, what's your fuel pressure at wide open throttle? I'm guessing you know about the lift pump failure problem with these 98. 5-2002 24 valve trucks? It's common to see fuel pressure drop correspondingly with throttle pressure. But a whole lot is not good. Below 7-8 psi at WOT is a no-no.

The Powermax3 or any other fueling box will not directly cause the VP44 to fail. It may, however, accelerate the demise of a flawed VP44 (and they are out there). I've replaced injection pumps on 6 trucks, and four of them were '99 models.

As for your high EGT/ "overboost", I experienced the same thing with both a Power Edge (now marketed as an Edge Pulse) and the Powermax 3. I went to an Hx40 turbo, and it made all the difference.

BTW, I have a 2001, also. At 120,000 miles, 104,000 of those miles at power levels above 450 HP, and running a TST Powermax 3 Comp(duty cycle is 60%-65%, which can wear out the pump solenoid FASTER than the regular Powermax's safe 55% maximum) I'm still on my original VP44. I don't see how... . I've run it out of fuel accidentally three times, too... . The sixth & last lift pump was Cummins PN #3990105, it has lasted over a year.

 

[Huff N Puff]

Dont see anything about size of your turbo charger

I suspect you are over working a small turbo to achieve the boost you have. If you have too small an exhaust housing,you may get enough boost but it will drive your EGTs too high. Hope this helps. Merv

 

[Huff N Puff]

Thought of one more issue

Make sure you are not restricting the incoming air flow to the turbo. See if you are pulling the filter minder down. You also need to pull in cold out side air, as opposed to pulling in hot air from the engine compartment. Merv

 

[voice of reason]

Ready for this? Would you believe my LP died last Friday (3 days ago)?? HMMMMM... I wonder if maybe it's related? Gonna R&R it in the next day or two, do we'll see...



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