6.4 Dump truck no power/forced 1400/loss VREF

Aaron · October 23, 2009

I have an asphalt truck here with a diverter box installed right before the tailpipe diffsers, to force exhaust into the box to heat the asphalt. Had a P0272, P0652, 02138 and P2456. Truck had no throttle pedal response.

Found the diverter forcing exhaust to the box, set it to normal tailpipe operation and truck returned to normal with nothing else done.

Truck has had a PCM, pedal, and DPF pressure sensor installed at another facility. Could the 100 cubic foot tailpipe extension be causing the loss of VREF if the DPF pressure sensor goes out of range? It also appears the DPF is damaged - black smoke at a WOT snap.

As per FMC - no modifications of the exhaust is permitted - have spoke with body builder they claim no other reports of this type. Any ideas, ladies and gentlemen?

Been chasing this everywhere, found no chafes at any of the known locations, no spread pins anywhere, and I can't recreate the concern now.

VREF stays constant at all times, truck is at the latest cal, and like I said - has new APP/DPF Pres/PCM parts cannon unloaded on it.

lmorris · July 16, 2012

This is #2 for me. First one was on it's way to California from an auction house just up the road. Stock F350. Same symptoms, had new pedal before we got it. Acted up twice for me then started working fine. No chafes found anywhere. DPF working fine. The current one in my bay has a new DPF in it. But has since been in twice because they don't let it regen properly. Is not currently acting up. They said it quit on the highway.

Could this be a result of very high pressures at the DPF?

Any others found this issue and managed to fix it?