2003 S80 T6 Trouble codes P0420 and P0430

Mark27 · Post by **Mark27** » 13 May 2014, 08:40

Hello Volvo enthusiasts
My OBD II is showing two codes P0420 and P0430. I know these two codes are related to catalytic converter efficiency but wondering/hoping something else is the cause besides the cat. In addition to the codes mentioned, code P0234 (overboost, pressure too high) appears. I cleared all codes after checking for obvious vacuum leaks (for example, loose and cracked hoses etc ). The two codes P0420 and P0430 consistently re-appear after a few miles. I also feel hesitation when abruptly accelerating (turbo) at any speed and I hear a high pitch air intake/sucking sound. After the hesitation, the car accelerates and hesitates a little more. Could the poor performance and converter codes be related to the turbo trouble code, P0234. I’m attaching a picture of the “Rich to lean threshold voltage” and a word document containing the freeze frame data that was recorded at the time the codes happened. Thanks in advanced for any help provided.

Mark27 · Post by **Mark27** » 13 May 2014, 17:38

Update:
The MAF sounds as if it is having a asthma attack when I press down on the accelerator petal. When I removed the MAF so it could be cleaned, a section of the housing was not intact (one side was lifted exposing the electronics it was housing). Is there a specific code that would appear if the MAF isn't functioning property.

matt5112 · Post by **matt5112** » 14 May 2014, 12:32

Sounds might be a leak, and unplug the maf and see how it drives. It should behave better if the maf is at fault.

Mark27 · Post by **Mark27** » 14 May 2014, 19:23

Additional update:installed a new boost solenoid and cleared the codes. The new system readings indicate all previous out of specs are now in spec. Conclusion. Turbo solenoid was malfunctioning. Thanks Matt