1999 3600 T444e won't rev in first gear

[cadillackid]

the sensor near the Y should be the MAP.. it shouldve turned on the WARN light when you unplugged it and will set a code.. you can read the flash codes with the diagnostic button near your 6 or 9 pin round connector. the only scan tool that will correctly read the IH data is ServiceMaxx on a Nexiq or clone or if he has a true MD / HD scan tool he can read it but some of the universal tools dont do a good job esp with the older 3 box systems.

[rlg999]

That's exactly what it did. As soon as I unplug it, the warn light comes on, and sets the map low voltage error code. The guy down the road is a heavy diesel mechanic, I think he has the good stuff for working on the trucks... We'll see...

[cadillackid]

Have you actually tested for boost leaks , turbo failure , etc? It’s possible the computer slows down fuel if it doesn’t see a normal progression of boost build.

Bill would know more of the 3 box system has the algorithm to secure on low boost …. Of course the diesel mechanics scan tool will show what it thinks the boost is.

[rlg999]

What is a three box system? I've got the big ecm on the side of the engine. I think I've eliminated fueling and boost issues, because it runs great with the map disconnected. If I could simply get a part number for the factory map sensor, I think I'll be ok. I don't think it has the correct map sensor installed. It hasn't ran right since I bought it, and it has had other weird stuff done to it elsewhere, so who knows what parts they have swapped out before now. I may need to start a new thread, this one is too long and no one is reading all the stuff that I've gone over so far. Thanks for all the input and help.

[cadillackid]

Sorry o got you mixed up for some reason I thought you were a 1995 year, that’s another 444e I was talking to someone about.

The best way to get a good part number is to call an IH dealer with your VIN, act like you need the sensor , get the price and part number. If it’s not crazy just get it there.. or you can order it online.. but I’ll say that many have had issues with cheap crap online like dorman brand. I buy the name parts like Alliant or reliance and haven’t had issues.

[rlg999]

No worries. I appreciate all the input. I called the IH dealer in SC today, and he quoted the same 1840078C1 part number for the Map sensor that I put in and had to return. But that one was from Amazon, I believe. Like you said, Cadillackid, the OEM ones are probably the only ones to use. I'll have it tomorrow, so we will see!

[rlg999]

Well the $140 genuine International sensor did the same thing as the $20 Amazon one did. Sluggish and wouldn't build boost. Checked the voltage and resistance of the harness. <5 ohms to gnd for pin a, more than 1k ohms to gnd for pins b and c. Power on engine off, I had 5v at pin b, .8 at pin c. While driving, pin c never got above 1.7v. Should go close to 5v at full boost. Ohmed out harness and pin c to pin 30 on ecm checked out good. Removed connector and she runs like a scalded dog. Guess I'm going to have to live with the warn light on all the time. I bet International won't be as accommodating on returning the sensor as Amazon was. UGH.

[rlg999]

Could there possibly be some sort of "Low HP tune" installed on this ECM? I think the PO said it may have came from a military base or some other gov agency. Maybe they have it set to some crazy low hp for safety?? I know nothing about the T444e programming and how it is set up. Once I remove the map sensor connector, maybe the default fueling program is higher than what this thing is programmed for??? Sounds crazy, I know, just grasping at straws right now.