I have a 2001 7.3 255,000 miles. Not sure of previous mechanical history.

Background, truck would not start without being plugged in. Replaced GPR and GPs and the truck would crank but not start. Found one of the high pressure lines leaking where it connects to the Hpop. The fitting was not even torqued, I replaced O rings and tightened everything back up. No more leaks and the truck starts but I am seeing a long crank time. It seems like it "rolls" into a start, cranks but doesnt really start to fire until after around 10 seconds.
Now my ICP sensor plug is full of oil, I felt like it even ran better after I unplugged the sensor.
Would a bad ICP cause a long crank or do I need to replace that and continue on.
I have AE so I am going to hook it up tomorrow but I assume it will not read the pressure right if the ICP is bad?

 

If the ICP is bad, it will read an incorrect pressure. But that's a good thing since you'll be able to see the pressure looks out of what's normal and make it easier to diagnose.

 

Can you rephrase that last sentence?

 

You should see a default of 725psi ICP if the sensor is unplugged, but a bad sensor will be anyone's guess. What it should be is about 550-600 at idle, 1700 or so cruising, and 3000 +/- at WOT.

How does it run after starting (if you can)? My somewhat educated guess would be a worn HPOP or a possible injector o-ring leak. My father-in-law is dealing with the same frustrating situation as well.

 

If the ICP sensor is bad, the pressure you see on AE won't be in the normal range.

 

It starts every time and runs great. Just extended crank time and the injectors dont seem to start firing until after a couple seconds of cranking.

 

Does it start easy once the first start is out of the way? If so, it could also be the hpop reservoir draining down a little bit and it takes a few revolutions for the Lpop to fill the hpop. Check the oil level in the hpop after it's been sitting awhile. The oil should be...I can't remember if it's an inch, or 1/4 inch.?

 

The IDM won't fire the injectors until the PCM sees about 500 psi ICP, IIRC. If you watch injector pulse width, you should see it jump from .5 ms which is standby, to about 2.1 ms when the IDM starts firing the injectors. With the ICP sensor unplugged, the PCM uses a default value of 2200 psi ICP while cranking. If the truck starts fine with the ICP sensor unplugged, I'd suspect a bad sensor. If the connector is full of oil, it should probably be replaced anyhow.

 

You will want to watch the icp,(injector control pressure), duty cycle( can't remember if it's ipr or icp), and I guess fipw(fuel injector pulse width) "never actually watched that". Maybe even record your results starting it so you can review it or have it reviewed. Good luck. Let us know!

 

Thinking about what you said about changing an o ring, you may just have a lil air trapped in a rail.
How did I crank before with it plugged in?

 

Standby for the Fuel Injector Pulse Width is 0.6 ms. This indicates the IDM and PCM are synced. If you see 0.0 ms, you have issues to resolve - either with the computer connection, the software, or the truck. Many versions of AE have a messed-up multiplier for the FIPW. The solution is to go into the PID configuration for the FIPW and set the "scale value" to 10, then you will get accurate readings.

When you messed with the HPO line, you introduced air. This means it will take about 50 miles of driving before you can accurately evaluate your crank time again.

Long cranks are not usually an ICP sensor issue... the injector O-rings and injectors are the most common cause of this. When you first start the truck, set AE to log FIPW, ICP, IPR (ICP DC in AE), RPM, and Battery Volts. The graph should show what is below minimum (color-coded arrows in graph below) before the engine turns over.



If all is well there, get the truck good and warm, then do some WOT runs. The log should then show about 35-38% IPR to get about 2500 PSI ICP on a stock truck. If your truck is tuned, then you may need to share the log to suss out what's going on.

 

Thanks for the replies. I need to figure out how I can record vitals with AE so I can share them in a chart/graph format.

Regarding how it starts plugged in, same as it does not plugged in (at least while it is 70 degrees out).
It is supposed to snow tomorrow so I will be interested to see how it starts then with new glow plugs and GPR.

I will replace the ICP as the sensor is full of oil. Out of curiosity, what causes the sensor to start leaking oil and is the only way to fix it to replace the sensor?

 

Almost everybody will say once it has oil, it's time for a change. I cleaned mine with electric contact cleaner and applied fresh dielectric grease - this got me back to normal operation. My ICP sensor had 13 years and 275K miles at the time, so I replaced it as a maintenance item.

You can try cleaning it, and there's no certainty that you are having a problem with it now.



The log can auto-name, but if you record more than one log in the same day, the second recording will erase the first recording. To play it safe, give your log a unique name each time... something that will help you identify it later.

 

Thanks Tugly! Been swamped today so I did not get a chance to work on it. Will report back tomorrow

 

Sorry guys, have not had a chance to work on the truck the last couple days. Started it in the cold weather yesterday and today and it starts just romps pretty bad for about 10 seconds, that is another issue.
Kind of sick of it.
Went out tonight to try and data log starting and driving with AE.
Will not connect to AE, will not connect to my other scanner. Two days ago I ran a buzz test with AE and had no issues connecting.
Seems like the OBD2 port is dead, I thought I heard a couple clicks under the dash when I plugged it in, not sure. Weird thing is that the cig lighter and power point still have power when I plug a charger in. Fuses seem ok, idk. Any ideas on why I cannot get a scanner to connect?