Possible throttle body issue

[lukeallen]

Okay I have a phase 2 172 which keeps hitting limp home mode randomly. The code shows up as p0120. Which it's throttle positions sensor/switch a circuit. What is the switch a circuit part mean? I have changed the pedal but cannot try it as it is a track car. But I have discovered that when the ignition is on but engine not running bury your foot to the floor and bam limp home mode but does not show a code on the reader. Do the same with the engine running, perfectly fine. Possible throttle body issue? The throttle body is making a lot of noise and i have noticed that when opening the throttle the butterfly doesnt open until around 2/3s RPM then it's wide open, is this normal?I will book a test day to know for sure that I have cured the problem before my next race. Any ideas in the meantime chaps?

 

[MicKPM]

I personally hate "p codes" as they're meanings are generic... and useless!

Sounds like you've got a throttle position fault which is being caused by a difference between the two pedal track values.

You are going to need the help of someone with some equipment to see exactly what's occuring to be able to properly advise in how to go ahead.

 

[lukeallen]

I was hoping it was going to be an easy fix but maybe it won't be! I have sourced a throttle body at a reasonable price which I know is a good one so will try that. If that fails would you take on the challenge of fixing it??

 

[MicKPM]

Easy peasey... just need to scope the pedal tracks and use CLIP to understand the actual problem and go from there.

As long as its not a 172 Cup #f'n things