I may have an ICP issue but am looking for some input.

A couple weeks ago I was driving up a hill and the truck quickly lost power and rpms. I managed to get it started and limped up the hill. At this point it wouldn't start. It sounded almost like a gas engine that was flooded when trying to start. After sitting for about a 1/2 hr it fired up running roughly. I got it home poped the hood and scratched my head.

The truck started running well again for awhile with off and on crappy running. Well a couple days ago it did the loss of power/rpm drop no start thing again. Right now it will start but will not drive. It will run for a bit then stall.

I have changed fuel filters. So after some research I pulled the heat shield over the ICP (my arm now looks like it has been through a meat grinder) and noticed no big gobs of oil in the area.

This morning I went out and looked again. I managed to knock off the little rubber gasket from the plug and it looked a little wet. I stuck the end of my finger in the ICP sensor and there is some oil there but not alot. Am I heading in the right direction???

I pulled my EGR and cleaned it. It was dirty but not too bad. Should it sound like a PCV valve when I shake it???

Help Help Help

 

if there is oil at the icp sensor connector then your sensor is leaking. yes the egr valve will rattle a little bit.

 

Could it be that you have water in the fuel system. When was the last time you drained water from the fuel line? What about the fuel filter?
Troy

 

He just did it.
Yes, if you have oil on the connector / sensor, that would be the first I'd go after.

 

Don't know if this helps, but it was something I read a while back ............

Is it the ICP sensor?:

If you have a scan tool or something that can read PCM data from the OBD-II port, you can troubleshoot.

With the key ON, but the engine OFF, what pressure should you see for: Oil, ICP, Boost (MAP), Exhaust Back Pressure (EBP)? ZERO! If you don't get that, then something is wrong. Now, the ICP sensor, since it has 100 TIMES more range than any other pressure sensor, is ALLOWED TO SHOW some ICP with the engine off. If ICP is less than say 40 PSI (KOEO), then that IS NOT your problem. Is it absolutely "right", nope, but it also is not the cause of a problem. Any ICP reading under 15 PSI (KOEO) is perfectly OK and you SHOULD NOT attempt a repair.

Now, it can happen that an OLD sensor gets a "dead spot" in it where it reads ok at KOEO, idle and WOT but somewhere in the middle - where it operates for extended periods (like highway speeds) it has a spot were it does not read correctly and "jumps" or sticks. This IS difficult to verify, so you need careful input from the operator to find this.

 

If the Icp checks out I would think 0-ring or D-ring on the HPOP,or a fitting leak.Its a pita to check the HPO system on the 03 but that sounds like a small leak in the system to me.

 

Sounds like the same problem I had. Cutting out and would not restart after driving for a bit. I would turn the truck off and sometimes it would not restart and just crank for days, unplugged the ICP and it would start right up. Put an updated ICP and connector in, although I already had the updated connector, and the problem was gone. Oh and I also had a hunting idle since I bought the truck and it went away. Also to note just the sensor replacement did not cure it as I got the sensor in the mail and installed before I had recieved the new connector.

 

Many thanks to BowTieHatr ......................................

He PM'd me and pointed out that the information below (from an earlier post of mine) is not accurate. I have not been able to locate the original post that I copied this from. I usually copy the reference link along with the information I save, but this one I didn't. Please disregard the information posted and sorry for any inconvenience.

I'll do a little more digging to try to clear it up .................

 

Thanks for the info guys. I changed the icp because it was leaking, but it didn't fix the problem. I bit the bullet and took in to a shop. after some testing and code reading turns out I have a bunch of bad injectors.

Once again thanks for the help.

 

ZIP. There is an updated connector for the ICP on your truck,if the wiring hasn't been spliced you need a new one.(Bismic will know the part number)My money says the HPO system is bleeding off pressure and eating injectors.

 

Thats what my problem was, the ICP connector, although it had already been updated/replaced.

 

hey guys... a smidge off topic, but... where exactly is that ICP located? I'm trying to hook up a Hpop gauge and I can't find the darn thing. TIA~!

 

Thanks for the input guys.

From what I can gather there is an updated connector??? Is it updated or just replacing the old one. Mine had some oil on it but not dripping.

When the guy at the shop ran for codes he said everything pointed towards injectors nothing about sensors. He says he wants to do some more digging because he isn't certain that something else isn't causing the misfireing injectors. Of course more digging means more money on my part. I as well am not convinced that the injectors are bad.

I may bring it home tomorrow and do some more myself. At least he has me pointed in the right direction.

 

the connector is updated.

 

Thanks Mark!