Archived PCodes 0107 & 0073 Engine running rough and hesitation

[GJolicoeur]

04. 5 3500 4wd 83,000 miles.

A couple of days ago, truck started poorly, would have trouble keeping an idle. I drained some water out of the separator and threw some conditioner in the tank. It's running a little better - but the idle has gotten noisy - gravelly and knocking - more like my Gen 2.



The truck hesitates as I give it the gas going through the gears, pauses for 5 seconds, then goes. It runs and sounds great at full throttle.



It threw the codes (P0107 & P0073) this morning - but I don't know if that's related to the problem or not.



Is it safe to drive until I figure this out, or should I park it?



Should I be looking for an air leak? A weak or failing transfer pump? Or an electrical gremlin? Or injectors? Bad fuel?

 

[p-Bar]

P0073 Ambient Temperature Sensor High
P0107 Manifold Absolute Pressure Sensor Low
I was thinking transfer pump since I have same year and mine failed around the same but I know it threw a code in relation to the pump. I would check under the truck at the air conditioning compressor bottom side and see if the small loom of wires has rubbed through grounding out the 5volts for the sensors. Good luck

 

[GJolicoeur]

More diagnostic info

I checked the wiring and everything and I could not find any problems.



I probed the harness to the sensor on the air filter box and the supply voltage was within the specs in the manual. I probed the sensor and read about 280 ohms - also within spec.



I checked all the fuel lines at the tank and running up to the engine for leaks, cracks or tears, and everything looked fine.



I drove the truck to the local dealer, and on the way, it died while I was turning the corner. I restarted the engine, and, now everything is suddenly working OK!



So, I guess I can rule out bad fuel, bad computer or air problems. The dealer said that I might need an FCA?



I thought I might have had a stuck fuel supply check valve (replaced one on my '97).



Any thoughts on what spare part(s) I should start carrying around?

 

[GJolicoeur]

On the road

I puchased an FCA at a Detroit Cummins dealer for $100.



The truck started messing up again today - loping at idle and stalling - hesitating when I press the accelerator, then taking off.



I got home and put in the new FCA - seems to be running fine again.



Other posters were right about the screws, the heads strip easily with a T20 Torx bit. I was able to rescue them by tapping in a T25 bit.



Is there a way to fix the old solenoid?