Engine/Transmission (1998.5 - 2002) 234,112 codes, limp mode

[LTustison]

234,122 codes, limp mode

99, 2500, LB,5 speed, 3. 54 with service body, 8500# normal weight. I have been having 234,236 and now 122 codes come up. When the temp gets up to almost normal,160, it goes into what i think is limp mode. I runs, but won't hardly get out of it's own way. I have a temporary boost guage connected and the waste gate works as it should, opens 17-19 psi. I think i may have a bad boost sensor. And, the 112 code just came up today. anyone have similar problems and what was solution? thanks

 

[AggieJustin]

P0112 - Intake Air Temp Sensor Voltage Too Low

P0234 - Turbo Boost Limit Exceeded

P0236 - MAP Sensor Too High Too Long



If you're not running a box and boost fooler, I'd say that you're wastegate stuck closed at some time and caused the 234 and 236. The 112 looks like it might be a bad IAT sensor. You can pull it out and clean it to see if that helps. You can find the resistance values in an old post on here about IATs.

 

[LTustison]

Thanks for the reply. I mistakenly said 112, and it is 122, tp sensor, and i have had a gage on it when it said 234 and there was never anything over 18. 5 psi. This is a stock truck with only 4"turbo back magnaflow exhaust and K&N air cleaner. I have a code reader and can erase the codes, and have, to check if something I try does any good. So far nothing has changed. The 122 is a new one to come up.