Engine/Transmission (1998.5 - 2002) Engine cuts in & out (MAP ?)

[turbo torque]

When Im just going down the road, not under a load it seems like its defueling, cutting in & out. If I put power to it she takes right off, as soon as I back out of it, it will cut out. I disconnected the comp and, no change. Code 0235 comes up (MAP sensor voltage to low. )



Could a bad MAP be causing this? Thanks, Bill.

 

[BSeitz]

Take your map sensor out and clean it off with some break clean or contact cleaner. That usually works instead of just buying a new one. Might want to pull your IAT sensor out and do the same while your there. It's right behind the map sensor. It's the same size socket.

 

[BSeitz]

I forgot to mention how much soot can build up on those sensors. Good luck.

 

[EricBu12]

Im having the same thing happen. . Even when I just rev while parked at about 1400, cuts in and out. . every few seconds... no code other than 0500 but that is because of my tru-speed adjuster. . it is working properly. . I have a FASS and the pressure is above 15 steady.

 

[turbo torque]

OK, MAP sensor came out real easy w/ 1 1/4" deep socket. It was shiney clean with a little oiley residue but I am running 100% bio right now. I cleaned it up good with brake- klean and air pressure and no change. It seems worse when warmed up. I did change out IAT last summer. If I try to maintain any consistant speed it de-fuels and bucks & jerks real hard, Hit the go pedal and all is fine. As soon as I back out of it she de-fuels again. It seems a-lot like the APPS did in early state of failure, except no go-pedal responce then. Any ideas?? Thanks much, Bill.

 

[blacksheepdiesel]

Swap your APPS with one from a manual transmission truck that does not have any symptoms and see what happens. My bet is the APPS. Order an aftermarket one from timbo here on TDR.

Godspeed,
Trent

 

[turbo torque]

I am a manual transmission, I don't think its the APPS, code 0235 MAP sensor voltage to low. Just wanted to know if a faulty MAP could cause it to defuel when not under a load.

 

[blacksheepdiesel]

Don't know about the faulty MAP causing defuel but I have had several APPS go bad with no code set.

Godspeed,
Trent

 

[EricBu12]

I am still having trouble with this. . I have replaced the APPS with the timbo one and The VP-44 is only 14K old. . I bought it from Industrial Injection here in Salt Lake City. .

My problem seems to happen when the temp is like 190 and I accelerate. . it defuels for like 2-3 seconds then goes. . As I said before. . if I am parked and rev to 1400 and the temp is 190, then it defuels every few seconds until the temp goes back down. . it don't do this when it is cold.

 

[blacksheepdiesel]

Have you cleaned all the grounds? There are a bunch.

Godspeed,
Trent