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Posted this to a several year old thread with little response, so thought I'd post a new thread and see if I can get some help with this.
Had my '03 F350 7.3L (126K original owner miles) in for some bodywork, and after having it 6 weeks, it came back looking GREAT - but with the Check Engine light on. Body shop scanned and it gave a P1280 code, but said they did not do anything to cause it, so I'm stuck fixing it. Had one VERY rough start - like only running on half the cylinders - but has been starting OK since, though I'm not driving it more than around the neighborhood as I don't want to get stranded! Found this thread and have checked the ICP sensor connector pins A & B per F350-6 diagram. ICP connector bone dry - no oil in it or ICP. Would move on to checking pins back to PCM, but - is 2003 F350 7.3L ECM pinout the same as 2002? Did not want to make a wrong assumption that it is. I'm assuming I need to pull connector from PCM at the firewall? Any way to read/check the ICP itself? I do not have any scan tools - just a DMM & 12V test light.
Truck runs the same with/without ICP connected. Have fairly new Motorcraft batteries, but have been noticing tougher starting in cooler temps. GPR voltages check out with DMM, so thinking I may need to replace glow plugs as well - unless ICP could be responsible for that too, though did not have Check Engine Light until the bodywork. Is 126K miles about time for new glow plugs? Was due for oil change, so have already changed oil & filter (Rotella T4 15W40 & Motorcraft 1995) as have seen some info that could be partly responsible.
Did find a pink (orange??) wire rubbed through the insulation against the valve cover between the connector mounted to the driver side valve cover and the ECM, but lifting it off the valve cover did not change the idle or clear the CEL. Also noticed what appears to be an original screw/bolt that comes down just ahead of the cowl and right into the harness where it attaches up under there - about dead center in front of the steering wheel. Found a new OEM Ford IPC sensor on ebay for $135 and will have that to try Friday. Can anyone tell me if it would get fried if I still have an issue in the harness? THANKS!
Changing out the ICP is not a bad idea, if it's original, with a genuine Motorcraft part. You can drive with the ICP sensor unplugged to eliminate the ICP sensor as a cause if the rough running comes back.
Get yourself set up with a scan tool. Forscan Lite is $5 on your phone plus an OBDII wireless dongle - see thread below to get set up:
Have you performed the 50 cent mod on your Under Valve Cover Harnesses? Good preventative maintenance.
Sounds like the GPR is good. You can ohm out your glow plugs and see if they read open or high resistance. Use your DMM on the valve cover harness pins: Should read less than 2 ohms from each pin to ground.
Did find a pink (orange??) wire rubbed through the insulation against the valve cover between the connector mounted to the driver side valve cover and the ECM, but lifting it off the valve cover did not change the idle or clear the CEL.
A slather of liquid electric tape on the bare wire would be good. Then a hunk of split heater hose ziptied on the harness to prevent further chafing.
Originally Posted by MAC2003F350
Also noticed what appears to be an original screw/bolt that comes down just ahead of the cowl and right into the harness where it attaches up under there - about dead center in front of the steering wheel.
P1280 ICP code
