so im fairly new to power strokes and I just bought a 99 7.3. it is throwing the code p0107 and I have been doing a lot of reading and have not found much. the guy I bought it from says he changed the MAP sensor and it didn't change anything, I changed the pcm and that didn't fix it either. where I live I need it to pass echeck to get plates for it, and it wont pass with a check engine light on. if any one can help me I would much appreciate it.

 

P0107 - Barometric pressure sensor, Low Input

Assuming you have an early '99 (I believe the sensor became internal to the PCM as of '99.5), there's a barometric pressure sensor under the instrument panel on the left hand side, next to the steering column. It may have gone bad, or there may be a problem with the wiring. The sensor looks more like a relay than a sensor, and has a round connector on it with three wires. Gray with red tracer, brown/white tracer and dark blue/light green tracer. I'd go try to get a pic of it for you, but it's dark here now

 

Thank you for your response. I just went out to look and I dont see one so I would assume that means I have a late 99...

 

What is the build date on the door sticker? Through 12/6/98 is early '99. If the door sticker is missing, how many bolts are in the compressor housing of the turbocharger (assuming it's the original type)? 4 bolts is early '99, 5 bolts is '99.5 and up.

 

There are 4 bolts on the housing.

 

Here's a pic. It's the square, black one with the Ford logo, next to the brown connector. I guess I should have said it's on the left side of the truck, but to the right side of the steering column. Sorry if I made that confusing.

 

Here is a picture of mine. I dont think its external. <br/>

 

Well, that's odd. If it is in fact internal, the PCM is faulty. Do you have the Ford part number or the code (something like XLE4, PMT2 or the like) from the PCM you installed?

 

F81b-14a097-af

 

I just looked it up, and what I thought about the build date appears to be correct. If it was built before 12/7/98, it should have the external sensor. If it was built on 12/7/98 or later, the sensor is in the PCM.

 

Hmm well thats weird. Thank you for all your help

 

That doesn't look like a PCM part number for a Super Duty. I can't find it anywhere; not even Google turns up a valid result. A PCM part number, or at least all the ones I'm aware of, have 3F as the third and fourth digits, i.e. XC3F, YC3F, etc.

 

Don't give up just yet, lol. I'm sure someone here can get this worked out, even if I can't take it any further. There are a few people here who work with PCMs and tuning a lot. Is the truck an F250/350 model, or is it a 450/550?

 

Its an f250. Thats the number I found on the white tag maybe there is another number I cant see I will go try to see if I can find another one

 

OK. If the door sticker is there, double check the build date, too. That could shed some light on this pretty quickly. I did find some PCM update codes that start with F81F. Is the truck a 6 speed?