Engine/Transmission (1998.5 - 2002) Sudden momentary power loss

[petersonj]

2002 Dodge 4x4, 6 spd, engine never modified except for exhaust brake.



Problem only occurs when ambient temperature is 90 degrees or above. The conditions are: usually 5th or 6th gear, with a light throttle and always a light engine load. It doesn't matter whether the truck is fully loaded or empty.



The symptoms are sudden, as if 75% of power was turned off. The engine still runs smooth and there is still throttle response, just reduced power. It usually lasts about 10 to 20 seconds, sometimes longer. The power fully returns on its own just as suddenly. The problem never occurs under a medium or heavy engine load. If the weather cools down below 90 degrees, the problem never occurs at all. All gauges are always normal and the check engine lamp has never came on. Other than occasionally be driven nuts by this problem, the truck runs fine. Any ideas?

 

[JKinney]

VP44 dieing.....

 

[rweis]

Check your P-ECU codes. I would bet you have a 0216. I would bet the electronics are going in the VP. No choice but to change the VP. Hope you can do it under warrantee.



What's your mileage?



BoB Weis



There is a vote thread about losing the VP for 2nd gen.

 

[CyberRanger]

That's exactly what mine was doin' prior to today. It threw a 0216 code & the pump was replaced this mornin'.

 

[petersonj]

Thanks for your response. The mileage is 85,000. The first time it happened was last year in August on a trip. The mileage was around 65,000 then. After I returned from my trip, I temporarily installed a fuel gauge and left it on for a few days. I had the gauge installed before and after the fuel filter was changed. The lowest pressure I observed was about 4 psi under full throttle at 2500 rpm. Of course, the engine never malfunctioned during the test, or for the next several months.



After your response and reading some other threads, it's looking like the the VP44. I'm going to try to get some codes. Thanks, again for your help. John

 

[rweis]

On a PM from a person that works in a Bosch rebuild facility and what he sees as far as to why the VP's fail:



You need to maintain 15 psi at all times. Virtually without a doubt every VP that has low fuel psi will fail. 10 psi is BAD.



Heat from low tank probably accelerates failure.



Just some ideas,



Bob Weis

 

[RJPotts]

Yeah, I think this fuel setup is garbage, these 24 valves really are looking for any excuse to just die. My VP failed under the same conditions but it wasn't heat related the first time, it was a bad LP a long time before I bought the truck, the next time it will probably be VP electronics, if I haven't sold it for a 12 valve before then.

Rest assured though the "dead pedal" will get much much worse.

-R. J.

 

[rweis]

The only forward movement I see in the VP arena is over on the BD web site. I went looking for it and could not find it immediately, but the gist was that BD has the UPS (or FedEx) VP44 that the company got Bosch to build a tougher VP44. Apparently it has more durable electronics and some aluminum pins / shafts were converted to brass. I think I remember BD wanted $1600 for the upgraded VP with a $1400 core charge. Significantly higher than other VP cost, but might be worth the difference.



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It was Blue Chip Diesel, not BD, go and read their writeup about the FedEx version. BlueChipDiesel.com edited 7/28/2005 Bob Weis

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Somewhere here on TDR in the last couple of days there was a good post about how the VP electronics fail from heat cycles. Something like the board solder joints slowly crystalize from heat cycles and then loose connectivity.



I am going to try to run very cool fuel (80* - 100* regardless of tank level) (fuel cooler, return fuel to filler neck instead of the fuel pickup cannister) to try to keep the VP as cool as possible, and a RASP (FASS etc) to insure 14 psi at the VP inlet at all times and see if that will help the VP longevity.



There is a thread about someone working on a solid state cooler for the VP electronics like the DC chest coolers have in them.



When I shutdown I think more of the coolness of the VP than the coolness of the turbo (both of course, but more of the VP cooling down). A shutdown timer might be more beneficial to the VP than the turbo that is always its marketing point.



Lots of questions, few answers,



Bob Weis

 

[CyberRanger]

I was told my VP44 failure was due to electronics, NOT a defective lift pump. While my lift pump was replaced (3 wks ago) due to low pressure it never got lower than 5psi under a full load & usually ran around 10-11psi at idle.