2003 6.0

The truck sat for 3 or 4 days after this problem, then i drained the fuel/water separator and it had probably 1/4 gallon come out of it. Truck ran perfect for 3 or 4 days, then 2 days ago i started it in the morning, idled fine and everything for about 10 minutes. Drove perfectly for about 1/2 mile, then it started shaking and idle continually dropped. I let off the gas and the truck died and coasted to a stop, and wouldnt start back. Acts like its not getting fuel periodically.

Had a friend come look and he said it sounds like an ICP sensor or an IPR valve. Does this sound right judging by the original post problem, then this problem. Why would it run for 3-4 days probably 250 miles perfectly..?

I searched and found that these 2 things have similar symptoms. Need to get this thing running so i can sell it. I dont want to take it to a shop so im going to attempt it myself.

Thanks in advanced guys.

 

Here is the original post/problem

So i start the truck this morning and it starts perfect and after warming up drove it halfway to school. About halfway i thought i had a flat tire becase the truck was shaking, after pulling over and getting out of the truck i realized it was the engine. It was idling violently and shaking the entire truck at a dead stop. Pulled back onto rode and had 0 power until 5 mph, then it was sloppy, will not go over 35 mph.....

 

Have you tested the FICM? do you have EGR delete? if not then I would pull the EGR valve and clean it up. If you susspect the ICP sensor then just unplug it to see if it improves, drive it for a while with it unplugged and see if the symptoms go away, if so then replace the ICP sensor

 

Have not tested the ficm, didnt expect it to be bad only being 8 months old.

Ill unplug the sensor this weekend and clean egr valve.

If the symptoms go away with it unplugged its bad? What if they go away can i just never replace it and leave it unplugged, or will this damage something? What exactly is the point of the sensor?

 

Doesn't sound like a ficm to me sounds more or less air in the fuel f anything is replace both fuel filters and check for fuel leaks

 

with the ICP sensor unplugged the computer will give a default reading of 2000psi for High pressure oil, the ICP sensor and the IPR valve work together to keep the high pressure oil at the desired amount, rpm,load,temp all help determine desired pressre. At idle you might only need 600psi so if the pump is puttting out 750psi then the IPR valve will open some to drain off excess pressure but when you step on throttle th desired might go up to 3000psi so the IPR valve will close up till the ICP sees it is making that 3000 psi. The HPOP can make over 4000psi that is why there is need for something to monitor actuall pressure/ICP sensor----- and that is why there is something to regulate pressure/IPR valve.
You can drive with the ICP unplugged but if you really jump on it it might not run right or if you tow a really heavy load it might not like it. If unplugging it clears it up then yes, the ICP sensor is bad.

 

I'd say icp sensor, if and when you change it out, change the pigtail as well and use some contact grease inside the plug in case oil gets in the new one too. If not icp, test the ficm for voltage, also connectors on back of ficm are really finicky. If one is even a little loose you'll have issues. Good luck. Btw, Icp from the bottom is way easier.

 

I will check the icp when this rain/snow stops. How long of a process is it to get to?

 

sorry for bringing this back to life. i know this was posted over a month ago, but with college and work its been hard to do anything with the truck. now i have a couple weeks off school, so plenty of daylight hours to work on the truck. going to try tackling the ICP sensor tomorrow and unplug it to see how it does.

started the truck to idle for about 20 minutes one day to see how it did, i turned it off and left it for a few days. opened the hood yesterday and i see this mess... notice the rat poop in the first picture


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could my alternator be boiling the acid out of my batteries? hope i dont sound like a moron, but is that possible...? im going to check voltage on the alternator tomorrow, what should it be when running?


also decided it was time to clean the EGR valve out, and im GLAD i did...

she was a little dirty.. might be part of the issue

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If the voltage regulator in the alternator is bad it could over charge it, it should be between 13.5 to 14.5v at idle. a shorted battery would definately kill it. that battery might be shot.