Hi Guys- I hardly ever post - but spend hours reading info on this site. You guys are fantastic about sharing your knowledge.

Here is my issue - 2001 dodge. Last few months had fuel pressure and trans temp gauges put in. Noticed fuel pressure was WAY low - about 2-5 so had a FASS pump put in. Pressure went up to average 15psi.

Got a 5th wheel trailer about 12,000 lbs. Truck pulls great except for long steep grades blows a lot of black smoke and sever loss of power. Came home and had 3 codes I could pull with the key turn method. 0122, 0500 and non-helpful 1693. Took it to mechanic - determined vp44 probably shot due to low pressure for so long. Had that replaced. Brought it home and code 0122 still showing. I did the reset for the apps and now that code is gone. Pulled trailer again today - pulled a lot better but still sever loss of power on steep hills. No codes that I can pull. Any idea? I still have original stock trans. Could that be it? Trans temp got to 210 when it happens. Engine and oil temp are normal.

 

I am only guessing that there is no aftermarket performance device on your truck like an Edge or something. If so then unplug and remove from the truck to assure its not the problem.

The codes you listed pertain to speed sensors and the APPS. Not really related to anything you're having an issue with so maybe, just maybe what you're experiencing is a electrical problem. That being that maybe the batteries are not in the best condition (a dead cell in one), or that the major cables and/or grounds are loose or corroded. Or.....a common issue is the alternator is creating AC noise which is creating an electrical anomaly. Excessive AC noise can cause the APPS to act weird and it can also cause the transmission to freak out.

Other than that, usually excess black smoke under a load is an indication of a boost leak. Do you have a boost gauge?

 

I think your on to something there KATOOM, a boost leak.

Running unloaded there is much less demand on the engine load wise, so boost would be less than towing. A boost leak would be much more noticeable while towing than unloaded.

 

Thank you both! I will have it checked for a boost leak. I do have an Edge EZ chip - but it is always set at level 1.

 

Honestly you should have all the necessary gauges to monitor your truck. That being a boost gauge, a pyrometer for EGT's, a fuel pressure gauge, and a tranny temperature gauge if you have an automatic. This way you always have an understanding of what "normal" is on those gauges, and when somethings not right then you can refer to them for diagnosis because usually when a issue arises one or more of those gauges will read different.

Aside from that, remove the Edge and see if the smoke subsides and the power maintains more steady. I say "steady" because obviously there will be less power but its the sudden drop in power you're not wanting.

And yes, have it boost tested for leaks. With the Edge on there you could have built just enough additional boost to work a rubber boost boot loose at the clamps. Those boot clamps are notorious for coming loose and allowing small leaks. Take a small wrench and crank them tight.

 

I think you are experiencing a "severe use of power". 12,000 lbs and a 8,000 lb truck up a steep grade...

Try that set up with a big block gasser.....