Hey guys,
Still working on my truck (05 F250) in my spare time, trying to resolve a hard cold start issue. Just replaced the two bad glow plugs this morning, haven't had a chance to start it cold since then...
Question is yesterday I was trying to start it to pull it in the shop, and it just wouldn't quite start. Outside temps were about 30°F. It sounded like it would have stayed running if it wasn't for the two bad glow plugs, however it just wouldn't quite stay running. I decided to pull the plug on the ICP sensor, and then it fired right off... I have not tried it cold since, but was wondering if that pointed to a bad ICP sensor, or something else?
I have checked the FICM, and have a SG2 so can monitor required peramiters... Just need to go do it once it gets good and cold again... She's parked outside cold soaking now...
Thanks!
Andrew B.

 

Unplugging the ICP is a field trick to get a truck started. The pcm has to see 500 psi HP oil pressure before it will allow the ficm to fire injectors. The pcm when it sees no signal form the icp uses a default setting of 750 psi. If the hp can actually deliver the pressure the truck will start.

So in your case you have a bad icp or wires from the icp. That is your problem.

 

I just changed mine tonight. It had been taking 4-5 sec. to start, then failed to start cold sat. morning. Pulled the plug and it was full of oil, new sensor and plug showed up today from Tousley.

 

mrfixit
Post thses sensor values at KOEO and LOW IDEL AND HIGH iDEL (2500RPM)


ICP
ICPV
IPR%
VOLTS
FICM MP
FICM LP
FICM VP
FPW (fuel pulse width)


so 3 values per sensor

 

Ok, just went out and started it up, drove it about 10 miles to get it warm for the sensor readings. It is ~20° outside, and it fired right up after about 3 seconds. Appears like the glow plugs may have fixed it! But, here is the sensor data anyway:


KOEO Cold Idle Hot Idle Hot 2500 rpm
EOT 21 ~40 199 199
ECT 21 ~40 191 191
ICP 0 1462 584 1350
ICV .23 1.55 .79 1.50
IPR 14.4 41.5 22.5 37.7
VOLT 11.4 11.7 14 14
FMP 47 47.5 48 48
FLP 11.5 11.5 14 14
FVP 11.5 11.5 14 14
FPW 0 1016 1050 640


From my limited knowledge of these, I didn't see anything out of the ordinary in those numbers. Let me know what you think!

I will let you all know how it starts one of these mornings when it gets a little colder here...
Andrew B.

 

Just a quick update to let you all know that the 2 new glow plugs apparently fixed my cold start problem. I cold started it a couple of days ago at -2° without being plugged in, after it was about -15 overnight... Started OK after cranking for a few seconds...
On to the oil cooler, and possably a weak injector... Lol!
Andrew B.

 

Those numbers look OK to me to as far as I xcould Tell

At those temps Glow Plugs Play a Huge roll getting the truck started