Engine/Transmission (1998.5 - 2002) Map Code

[JTHosler]

Hello all,



I have an issue with the truck and looking for a little input. I am seeing Map senor voltage to high code with the smarty, but no check engine light. The truck runs fine until you lay into the throttle. If you are on it runs fine until about 35lbs of boost then falls on it face (5-6 lbs of boost) smoking like a freight train. If you ease into it the boost climbs 35-38 and will stay there until you let off the throttle.



My question would what should I check? My thoughts are map sensor, comp box, or waste gate. Any input is appreciated.



Thanks,

 

[ThrottleJockey]

Is that the famous 'Limp Mode' ? Do 98. 5-2002 even have a limp mode? The Comp box should have a boost fooler, though. Did you check the grounds for all of your fueling accessories?

 

[JTHosler]

Not sure about the limp mode, I have not had a chance to check any of yet. I should have time as we have wrapped up harvest and just working on getting more ground worked this fall. Any other input is appreciated and I will post any findings once I get into it more.



Thanks,

Justin

 

[Midnite]

That's definitely NOT limp mode. Limp mode severely limits fueling when the computer doesn't get a particular signal it's expecting (and I can't remember what that is now). There's no way you could get lots of black smoke in limp mode.

It sounds like something is letting go of boost pressure when it reaches a certain peak level. I'd look at your wastegate or maybe an intake boot that isn't properly clamped.

Mike

 

[JTHosler]

Thanks for the replies, one more question. Would a problem with the wastegate cause a map sensor code? I am getting a map voltage to high code, but I will check that again with the smarty to get the exact code number.



Thanks,

Justin