Engine/Transmission (1998.5 - 2002) P0234 and P0237 code question help and wastegate

[EOwen]

I have an '02 automatic that has been throwing these codes for some time

now and have had "no pedal" until I get up to 1850 rpm. I have done the

disconnect the battery and turn the key reset several times but it keeps coming back.



I read alot here about the throttle position sensor and thought

that was what it was and went to the dealer to buy a new one. I just happened to run into the diesel mechanic in the parking lot on his smoke break and asked him about it. He said my codes are the "max boost exceeded and the MAP sensor voltage low" codes and have nothing to so with

the throttle position sensor and not to buy one. He said he runs into this all the time and that it sounds like I have turbo problems and a stuck wastegate.



My question is how does a stuck wastegate give me no pedal out of the hole?

I can barely get going to get up to the 1850 rpm when she kicks in.

I agree I have had an increase in boost but thought it was just my BHAF.



Also, the parts counter told me you can not buy a seperate MAP sensor for an '02 and that it was all part of the "bell crank throttle position sensor assy. "

The mechanic told me that was bull and that the MAP sensor is just behind the fuel filter assy. Is this true for and '02?



Thanks for any help you can offer before I start into it.

All this should be covered under Cummins 100K warranty correct?

I have 63K miles.



Eric

 

[KKlingbeil]

Correct on most of what you said, i think anyway. The map sensor should be seperate from everything else, and as your mechanic said it is behing the fuel filter assembly. The codes are right, over boost and low map sensor voltage. It is more then likely that your wastegate did stick shut, my 01. 5 has done it twice, both replaced under the 100K cummins warrenty. I would assume that the map and apps is also covered under 100K warrenty.



My exp. with stuck wastegate is that it had the same bottom end, but once the boost gauge hits 26 pounds of boost, the ecm defuels the motor so that is doesn't run any more boost. It will still accelerate and gain RPM's, but it will be a dog on top. I have not figured out why my truck had two different turbos have the wastegate stick shut. I think part of it is over idoling in the cold winter months of Iowa. Hope this helps