Without having a scanner to monitor pressures etc...ect I have a question about my icp. Can it be bad without the tell tale oil in the plug? I have thrown money and time at this truck with no luck. Tried unplugging the icp and still no start. New ipr....new cps...checked everything this site has told me to check and still good crank but no start. Checked all fuses and relays twice , have good fuel pressure to the bowl, opened drain and turned on key ....fuel shot out with good pressure... removed allen screw on top of oil res thinking i could see if i was building oil pressure (even tho gauge shows 40 lbs while cranking) and had wife crank as i was holding my finger the over hole and it blew oil from the hole (dont know if thats an appropriate test or not)...removed fpr thinking maybe it was dirty and spring was stuck....clean and spring not stuck...swapped out idm with known good one off my sons truck no start...put mine on his truck,and his truck started right up Pulled both valve covers to check uvch plugs even tho I had done the 50 cent mod a few years back.....all good.... Fuel filter like new with about 15,000 miles on it.....bowl heater wire not broken ...dash lights working normally....no ses light....wts on and off normally....tach moves up around 2 to 3 hundred....batteries good 3 mths old and have been on charger....all wiring seems to be in good shape ...none loose or chaffed....As you can see I have tried about everything with the exception of replacing the icp.
I am starting to think the icp is bad cause I kinda ignored it as there was no oil in the plug.
Also I get no smoke while cranking which tells me no fuel . Doesn't the ipc have something to do with the request for fuel? Please help....Truck hasnt fired for a week after all this...oh yeah...one other thing....I usually change my oil about every 8000 miles or so. It's overdue ,11000 miles since last. I read somewhere that if your oil gets thinned out pumps cant build proper pressure to fire injectors. Any truth to that?

 

My basic understanding of how it works is....

ICP is a pressure sensor that reads the pressure of the oil put out by the HPOP. It sends a signal to the PCM which in turn varies the signal to the IPR to open or close to decrease or increase the pressure.

As long as the HPOP is turning you have oil pressure at the injectors and as long as the fuel pump is working you have fuel pressure at the injectors.

When the PCM sees what it is looking for, i.e. RPM, oil pressure, voltage it instructs the IDM to fire the injectors. The solenoids on the injectors then begin to open and close using high pressure oil to force fuel into the cylinders.

In your case with no white smoke coming out of the tail pipe it would seem that the injectors are not firing or they are not getting fuel to push out. Either the PCM isn't seeing what it needs and is not telling the IDM to fire, or the IDM is not sending the signal to the injectors.

You changed the IPR but is the wiring to and from the IPR good. PCM may be sending a signal but IPR may not be getting it.

When you disconnect the ICP the PCM should use a default setting so if the ICP was bad you should still be able to start the engine with it disconnected.

With all the electrical signal and pressures required to make this thing run you can see why having some way to see it all is such a big deal when trouble shooting.

Need to make sure your IDM is getting power. Also check your PCM connection at the firewall and make sure it's good. Check the 42 pin harness where it crosses the driver side valve cover and make sure its not shorting out and preventing the signal from getting to the injectors.

I know I've left some critical item out. Will keep thnking about it and add more when I can. Also smarter mids will jump in soon and help us.

 

Does any body know what fuse feeds power to the IDM on a 99 f350?

 

Thx Paul. I know I need a scanner but can't find anyone close with one . Guess I am gonna end up having it towed to a dealer to get it running again. Don't wanna drop that kinda cash but am running outta options as I need the truck by the end of this week for sure.
All fuses have checked good as I have checked and rechecked them. 42 pin connector was checked when i had the valve cover off checking uvch plug. All looked good .No hot spots and pins looked in excellent condition.
One other off the wall thought. I recently had a cruise control issue and it turned out to be a broken wire on the clockspring (i think thats where it was) behind the ignition switch. Do you know if the ignition switch sends any kinda signal to the pcm or idm telling it all is good? Or is the fact that it cranks all that is needed from the ignition switch? In other words, could another wire be broken and something somewhere not getting a signal? I know it a long shot but I am grasping at straws in order to fix myself ....don't really have funding to have someone else tell me it's something i could have fixed!

 

I read but don't really remember but if you had a broken wire in the steering coloum
it will shut down the motor. Its common. I just don't remember if the motor will still turn over. If all this is good, sounds like HPO problem. I see you have a T500 so I wouldn't think that is the problem. Love mine and have one of the first built. You can have the dealer read codes and do the work your self. If its HPO they will replace both IPR and HPOP. It's just what they do. If its fuel related they still charge plenty for a pump and labor. So be really sure you covered both of them good.

 

Tin nut alert !

 

IPR completely replaced

 

I need to re-check the wiring diagram, but I believe the starter will crank even if everything else is electrically removed from the truck. A cranking engine doesn't necessarily mean the PCM, IDM, and FP are all getting the inputs/power they should be getting, it just means the starter circuit works.

The stealership in my area will charge me $100 to read the OBDII data before anything else takes place. My $400 investment in a fancy Android setup to constantly monitor the truck has already pointed the way to many repairs, and many "noises" to ignore. I have seen people get everything they need for $100: Cheap Android tablet with Bluetooth - $75. Elm327 knock-off - $15. Torque - $5. Torque Ford Expansion - $5. Those who get everything to work for that price are lucky.

This does have a tin nut sound to it, like the IPR may be ignoring the command to build ICP. Without monitoring all the goodies suggested in the last link in my signature, we are forced to throw darts.

 

11k on oil is way overdue. Good chance you aren't building enough pressure to fire the injectors with the old oil. May not be your problem but you are due for it anyway. I'd probably suck the oil out of the resevoir too.

 

I saw that. Wouldn't hurt to check if that thing is still there.
OP seems pretty pro so it must be something stupid like that.

 

Have you put a mechanical gauge on the oil rail yet? You can get a 0-3000 gauge at Harbor Freight, or any hydraulics shop. You'll need an adapter for the -5 ORB port on the heads.

 

Ipr was replaced...tin nut is secure.
As i was looking over things today I did notice the wires in the ipr plug were somewhat loose....would move in and out . Repaired that with 2 Part epoxy,but still no start. Did change oil and oil in res too.Still no start. After the last crank...pondering what to look at next, i plugged in my superchip to see if any new codes came up and sure enough p1280 was there. So i cleared it cranked again and it came back. Cleared again, unpluged icp....crankad again...still no start and p1280 was back. So gonna bite the bullet and get a new icp.....even tho the old one wasn't leaking. If thats not it....To the shop it goes......Learned a lesson tho.....plan on keeping the truck for a long time and I will get a scanner capable of real time scan! Period! Will let you guys know the outcome of the new icp.

 

No need to buy an icp sensor if it doesn't start with it unplugged. The 1280 is from cranking with the icp disconnected.

 

Before you pull the trigger on a new ICP, check the IPR wiring with a meter. Check for a good ground in the wire harness at the 42 pin. If this were an ICP issue the motor should start with the ICP unhooked as it would default to 700#. It sounds like your a good mechanic and know your way around your truck. This sounds (IMO) IPR related and is possibly something simple. Good luck!!!!

 

11K on oil is way overdue as has been mentioned (my oil gets loud at 5K from shear damage), but the fuel filter is toast as well. The recommended life on a fuel filter is 10K miles. I change my fuel filter every-other oil change to keep the injectors happy.