I have had an ongoing problem with starting my low mileage truck - ever since last winter when I had a dealer replace the CPS under the recall. The next day the truck would not start - no firing at all. Subsequently tried everything I could - replaced the CPS, checked all wiring and sensor connectors, fuses, tried unplugging the IPS, checked HPOP oil level, cranks good rpm, voltage good, tach wiggles while cranking, glow plugs flowing good current, no DTC codes - to no avail. Rigged up a gauge to check HPOP pressure while cranking, showed 200psi. Thought it might be a bad IPR. But then I got an advanced computer based scanner and software, one that can do system tests. This problem had been going on for months by now, and I connected the scanner - no DTCs, but unfortunately the vehicle is not OBDII compliant due to its weight, and I didn't have the special software to work with these non-compliant vehicles. Nevertheless, I ran the few basic checks that were possible with no indicated problem. I was rather frustrated, but then I hit the starter - it fired up immediately, but ran very rough. Ran it for some time - no improvement, but the SES light did come on.
This is too bizzare for words - fixing itself without my having done anything. I don't know if I will be able to get any codes out of it once I have the right software, but I can't imagine what could have been wrong. It seems electrical (faulty PCM?) Any ideas would be welcome.

 

We need more info on what year and model you have. I assume it's running now, but you said it was a rough idle, did it ever smooth out? How cold was it, do you have anti-gell in it? Also you said that the voltage was good. Are both batteries fully charged, when was the last time you checked them or changed them out. Will it start easier if you have the block heater plugged in for a while?

 

If the SES light comes on there will be codes.

 

Andrew, his thread title tells you year and model

Just razzing you. Sorry, I have nothing constructive to add at this time. Good advise so far.

 

It is a 2001 F350 dual rear wheel flatbed crewcab truck. It never smoothed out (ran something like it did once a year ago when one of the UVC connectors came loose - running on 4 cyl). It is not particularly cold (30s), fuel is good - the fuel heater is working. It is not cold enough for plugging in to matter (my problem has had nothing to do with cold weather - the vehicle was in my garage). Both batteries are fully charged.
The wierd thing is having HPOP pressure restored after having done nothing but connect a scanner to the vehicle and play around with it for a few minutes. It brings up reliability worries.

 

go ahead and pull the codes if you can. There will be codes if the SES light is on. Either your truck is very temperamental or there is an electrical connection is bad somewhere. Good luck

 

hook up a scanner and check the icp pressre while cranking.should be a min. of 500 psi.if not disconnect the sensor and see if it starts.if it does replace the icp sensor.

 

I finally got my scanner working and retrieved the DTCs. The only one was P0603, which is an error related to the KAM (keep alive memory).

After doing an injector buzz test, the following were reported:
P1272 - cyl #2 high to low open
P1277 - cyl #7 " " " "
P1274 - cyl #4 " " " "
P1276 - cyl #6 " " " "
P1278 - cyl #8 " " " "
P1294 - inj high side open bank #2

I am assuming this means connector problems with the UVC wiring?

 

sounds like it to me

 

It sounds like your harness is loose. Take a look and you can do the .50 mod to keep them from coming loose again. What type of scanner did you use to pull the codes and buzz test?

 

I have an autoenginuity PC scanner. I had a bit of difficulty getting the software working as my PC has Windows Vista.
It seems all the problems are on the left bank except #7.
I had heard of some mod for this problem - is it from Ford?
I wonder why this loose connector would have kept it from firing (developing HPOP pressure) at all for so long. Nothing in dozens of attempts.

 

After completing reconnection of the UVC harness and checkout (all tests complete successfully - KOEO, KOER, Injector Buzz, Cylinder contribution), there is an issue with idle at startup. It has always done this when it is a moderately cold start, temps in the 20s and 30s. It will fire up but the idle is surging fast/slow (monitoring IPR shows inj pressure going way over 1500 then back down). Pressing down on the accelerator pedal often causes it to smooth out and idle normally. There are no codes. It doesn't do this in warm weather, or even in extreme cold if it is plugged in. ???

 

Does it make a hissing sound or a jet engine sound out the exhaust when the idle is all over the place?

 

No - it will start to do that after it has idled normally for a few minutes in cold weather, as the computer picks up the rpm. I understood that this high idle was a warm-up feature.

 

Thats why I asked- some people hear that and think something is wrong. Sorry I can't be of any help.