2010 C63 p2123 HELP PLEASE
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2010 C63 p2123 HELP PLEASE
I am at a standstill right now. I have an issue with P2123 as a permanent code, accompanied by a P0300 Permanent code with a vehicle that runs smooth, idles fine, but has weird throttle response.
The car ran fine and had no codes or issues, and then sat for about 9 months, and then had these codes on startup. I replaced the battery and the throttle pedal right off the bat as those were high suspect from sitting, and also from some forums determined the pedal was an easy thing to just rule out real quick. Seems to have had no effect. Posted some videos with this showing me pinning the throttle to the floor while driving as well as parked, and you can see that the pedal is reading out at 90% ish when pinned but the TPS lags behind and only ever gets up to about 27% at the max. Removed and cleaned throttle body connectors, MAF, pedal connector, removed intake manifold and did a visual inspection on throttle body’s as well as made sure they were moving freely. Found PCV was cracked (or maybe I cracked it) while I was in there, replaced that while reassembling
Have tried looking through some forums but struggling to figure out next step. I have multimeter and did test for shorts or opens in the throttle body connections as best I could but forums I found didn’t do the best job of explaining so if someone has a good explanation of resistance checks I can do on throttle bodies, harness, and/or pedal that would be great.
Hoping it’s not the throttle bodies that are failed, seems like would be weird for them to just randomly fail while sitting unused.
Last edited by Thecarsondexter; Apr 13, 2025 at 10:25 PM.
