Runs crappy when warmed up - Diesel Forum

tntenter · 06-24-2009, 05:29 PM

Have a 2003 6.0 that seems fine till it warms up then it misses and runs terrible? Is there a sensor problem, also no codes. We have changed injectors, all the oil system orings short of tearing the motor apart. New High pressure oil pump, egr valve and sensor.

tntenter · 06-26-2009, 10:22 AM

no ideas on whats up?
Everything is fine till it gets up to operating temp then it acts like a bad injector. but i am almost certain it isn't.

Thanks

tntenter · 07-08-2009, 09:59 AM

still fighting this pig changed the oil stand pipe hopeing it had a weak weld that leaked upon warmup, but it wasn't.

tntenter · 07-13-2009, 01:51 PM

any ideas

southarkems@sbcglobal.net · 07-14-2009, 10:15 AM

a couple of things-check the crank shaft sensor, it will not give off any codes but this willusually cause it not to start. Also make sure the newest flash update is programmed at the dealer. Also you may want to try this it has helped me a couple of times and we were running four of these crap on wheels luckily we are down to two. Get a can of Sea Foam brand penetrating spray and crank the truck and set the high idle and open the intake hose behind the air filter and spray the sea foam in for about 30 to 45 seconds and let the truck run at high idle for about 30 minutes or so this cleans out al the coking in the turbo and intake.

rcgreg · 07-14-2009, 01:13 PM

Warm running problems point (in part) to the High Pressure Oil Pump system. When cold there is enough pressure to fire the injectors correctly, when the oil warms, pressure drops and then they misfire, ICP readings drop, the computer goes slightly bananas trying to fix it.
Step 1: MAKE SURE ! you have the CORRECT OIL - this is critical -
Step 2: MAKE SURE you have changed ALL THE OIL AND FUEL FILTERS
Step 3: IF above does not fix it - you need someone to read the codes as the engine is running.

MIne had the same symptoms - turned out to be an O ring in the high pressure oil rail.

Good Luck !

2004 f350 · 07-14-2009, 02:02 PM

mine will run fine but sometimes when im driving along it just starts running like crap for like 10 minutes, its missing then its fine again it only happens a once in a blue moon

djshum · 07-14-2009, 09:38 PM

I will almost put money on the icp sensor. The early builds (with icp under turbo) were very good for this. They can't take the heat. If you are using an aftermarket scan tool, it may not read the code, but with ford scan tool, will set p2285 I believe is the code #. If you have access to pid data, check icp voltage key on, engine off with hot engine. should be .18-.24 volts, they usually read well below .18 volts when this symptom occurs. If you find this to be the case, replace sensor AND sensor connector, as the connector usually gets oil intrusion from leaking sensor.