Help Needed Lumpy idle and rough cruising speed

[Eubee]

Howdy all. I need some help/input. This is the first diesel that I have owned and maintained myself. Grew up on a farm, so I have been exposed to diesels, but never got to wrench on them other than holding a wrench for someone else. We never had anything with this many electronics either. I am by no means a 'certified' mechaninc, but I can hold my own (electronics diagnostics aside due to not having a chance to learn them yet).

Truck:
2003 F250 6.0 2wd auto. Stock as far as I know. 166K on her now, 164K when I bought it. Bought it knowing it needed some work, but was mostly common maintenence for any vehicle (PSD or not).

Problems:
1- Lumpy idle up to and including operating temp. Sound reminds me of a mild cam in a built gas V8. Lumpiness does not go away as speed increases.

2- Along with the lumpy idle, when the torque converter locks up, I get a nasty vibration/shaking as if there is a misfire on one or more cylinders. There is no smoke out the exhaust. No CEL. Vibration/shaking stops if you let off the throttle; but picks right back up when the TC locks again.

3- First startup of the day is slow. What I mean is you can hear it cranking slower as if the batteries are weakening. Block heater plugged in for a hour or not.

All three of these arise imedieately after I installed a new ICP. I am talking first startup and drive after installing the ICP. With the bad ICP, the truck ran/drove/started fine, other than the oil leak and CEL. Checked today to make sure I reconnected all connectors that I recall unconnecting. Is there anything that jumps to mind, or is this another 'data log it and compare what the values are against what they should be'?

Thanks for any help ya'll can give me.

--Jess

 

[atk]

when you installed the ICP sensor, was it the correct one. when i did mine, they listed 2 sensor`s(my truck is and 04 with 03 motor)...did you change the pigtail(electrical connector) for the ICP? it could be oil soaked and won`t beable to send the proper signal. they (Ford) suggested to do this....

are your batteries good? it is very important for these trucks to have good batts(have them load tested)....check the connection`s too

if you do have access so you can do some data logging, you will beable to see if the ICP perimaters are with-in specs....

all filters and oil change been done?

another thing that does come to mind is the engine wiring harness. on the earlier trucks they had problems with harness chaffing and causing all sorts of problems....


hopes this helps some

 

[DaveBen]

A lot of people neglect the batteries until this time of the year. If it seems slow when cranking the starter, time for new batteries!!

Dave

 

[Eubee]

Thanks for the replies.

Both fuel filters were changed a couple days before the ICP, oil is still 'to-do". Oil is not due for a change yet anyway.

Batteries, they are a couple years old. Have not tested them yet, but will.

The day I changed the ICP the truck started fine (that morning). That evening when I started it up after installing the ICP, it cranked slower. Air temperatures were identical. Batteries were disconnected durring ICP replacement, so no drain possible.

The truck has a build date of 11/02, so I assumed it is an early build. The ICP I bought matches the ICP I took out of it.

Connector was not replaced. It was soaked in oil, so I cleaned it off very thoroughly with some electrical connector cleaner. There was no visible damage to the plug, so I decided not to replace it.

I am currently in the process of deciding which scanner and program to go with; but hope to have decided and ordered no later than Friday.

Have not checked chafing, it is on my to-do.

 

[DaveBen]

Go with the AutoEnginuity scanner and program. AutoEnginuity® - OBD2 Scan Tool - Professional PC and PDA Diagnostics for more info. Not the cheapest, but it is the BEST available. I love mine.

Dave

 

[Eubee]

Man do I feel dumb. I ended up taking it to the dealer to have it scanned. Came back with '#8 injector circuit voltage low'. The tech found the #8 injector harness was not plugged in completely. Plugged in, reset PCM, and all is fine now. I had not checked injector harnesses because I did not unplug any. A simple overlooked (by me) posibility due to being in a hurry.

I ended up ordering the Autoenginuity Ford bundle from ITP a couple days ago. Now I will not have to take it somewhere to get it scanned.

Thanks for the input.

--Jess