2000 5.9 fuel pressure fluctuates at idle, stalls, running rich
Legend
Joined: Nov 2014
Posts: 8,098
Likes: 318
The only thing I can think of anymore is, maybe, have you tried old school things like...going back to internal combustion engine basics, suck, crunch, burn, blow? It seems obvious you got spark, but how good and how reliable? Are the cylinders up to par and relatively close on their compression readings? CKP, CPM, and PCV valve n IAC all mopar? Hey you says these beasts don't like aftermkts in these places. How are your grounds, engine, battery, frame n all grounds to computer? Is the battery a reliable 12. something for start? The alternator, a reliable 13-14 something for operation? How clean is your alternator output voltage? Hell, I've even heard/read that only the original copper plugs work consistently in these beasts.
Thread Starter
|
Amateur
Joined: Nov 2017
Posts: 44
Likes: 1
From: Oregon
The only thing I can think of anymore is, maybe, have you tried old school things like...going back to internal combustion engine basics, suck, crunch, burn, blow? It seems obvious you got spark, but how good and how reliable? Are the cylinders up to par and relatively close on their compression readings? CKP, CPM, and PCV valve n IAC all mopar? Hey you says these beasts don't like aftermkts in these places. How are your grounds, engine, battery, frame n all grounds to computer? Is the battery a reliable 12. something for start? The alternator, a reliable 13-14 something for operation? How clean is your alternator output voltage? Hell, I've even heard/read that only the original copper plugs work consistently in these beasts.
I'll save you the long and short of it, but basically I originally visited two mechanics who couldn't figure it out. So hundreds of dollars later I took it upon myself and have been working on this particular puzzle for a couple years now on the back burner. At this point I can diagnose all of my friends' and family's and neighbors' car troubles, but this one is still mystifying...
Thus the specific questions about stalling, FP, and cat on our specific age and breed of engines - which, as I've learned, are big and powerful, but very delicate little babies that will last a long time if they're maintained and kept a close eye on.
That said, the fuel pressure issue and cat and stall queries have come up in my revisitation of the basics after lots of rough running. The adventure continues...
Record Breaker
Joined: Jun 2011
Posts: 2,387
Likes: 41
From: Bismarck, ND
Have you tried the map sensor? I was (am) having multiple issues with my v10 around idle. Bog on take off and rich/lean issue was caused by a bad map sensor. The stalling was the O2 sensors (and something else I have yet to figure out but it is much improved), and the unstable fuel pressure was caused by a bad battery temp sensor. Just unplug the sensor and see how the fuel pressure does. Mine improved immediately. Also since mine is a Canadian truck it has day time running lamps, and they always would flicker before at idle with the bad battery temp sensor.