Engine fault code

senatorjohn · **Posted:** Sat May 06, 2023 4:40 am

Anyone had experience with P0234, negative persistent governor deviation or know what page in the KJ Liberty service manual has information?

senatorjohn · **Posted:** Sat May 06, 2023 6:57 am

My scan tool came up with the weird code name. Over boost is the most common name given to P0234.

WWDiesel · **Posted:** Sat May 06, 2023 1:15 pm

P0234 -- Engine boost condition – limit exceeded Hose connection(s), wiring, TC regulating valve
See Section 11, pg. 9 in the 2005 FSM | Not a lot of detailed information in the FSM
A mechanical boost pressure gauge can be of great help in tying to diagnose a boost pressure related problem. :wink:

Quote:

TURBOCHARGER SYSTEM
DIAGNOSIS AND TESTING TURBOCHARGER BOOST PRESSURE
Several Diagnostic Trouble Codes (DTCs) can be set that will indicate high or low system boost levels.
There is a DTC for circuit faults relating to the electronically controlled wastegate command valve.
(Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER SYSTEM/CHARGE AIR COOLER AND PLUMBING - DIAGNOSIS AND TESTING)
for diagnosing of low or high boost pressure due to leaks.

layback40 · **Posted:** Sat May 06, 2023 6:49 pm

You could try cleaning the MAP sensor on the inlet manifold. Its hidden under the fuel rail, behind & under the rail pressure sensor.

WWDiesel · **Posted:** Sat May 06, 2023 11:30 pm

layback40 wrote:

You could try cleaning the MAP sensor on the inlet manifold. Its hidden under the fuel rail, behind & under the rail pressure sensor.

Great idea, or replace it with a new one. If you are still running the crappy EGR system, they gum up and soot up MAP sensors and cause many problems along with early failure.
Most replace the factory MAP sensor with the GM MAP sensor as it is less expensive and does the same job.
GM PN: 55206797 New GM PN: 55568175 IDParts has them!

Engine fault code

Who is online