E46 Idle Speed and Limp Mode Issue?

[dr_gn]

All,

2002 330i E46, 170k miles.

Been having issues with jumpy idle speed, then today the EML, Engine, DSC and a Brake warning all came on together, and it went into limp mode.

All reset and was ok for a mile or so, then the same.

Did a diagnostic and got a P0221 “Pedal position sensor/Switch B circuit range/Performance” error.

I’ve read where it can be the pedal or throttle position sensor from that code. Any ideas?

In the past couple of years the cruise control also occasionally drops out randomly, but there is never a fault code.

BTW I’ve changed the throttle body twice already since owning the car (about every 50,000 miles). Are they a known issue?

Thanks all.

[E63eeeeee...]

If it's not the obvious things from the error code, that sounds quite similar to what mine did when the idle control valve went. Has yours been cleaned?

[dr_gn]

E63eeeeee... said:

If it's not the obvious things from the error code, that sounds quite similar to what mine did when the idle control valve went. Has yours been cleaned?

No - don’t even know where it is!

[E63eeeeee...]

Just above the throttle body, it basically runs in parallel with the throttle between the intake pipes and the manifold, it's mostly hidden under the manifold. I bet there's a 50s kid video on it if you have a look.

Also, once you've cleaned it, put some oil or something in to lubricate the pivot points a bit or they can seize again quite quickly, they're not meant to be completely dry.

[dr_gn]

OK thanks.

[dr_gn]

Hmmm could be the throttle pedal sensor, which are NLA.

Might be looking at scrapping it...

[dr_gn]

dr_gn said:

Hmmm could be the throttle pedal sensor, which are NLA.

Might be looking at scrapping it...

I spoke to my trusted auto electrician earlier, and he thought it was a throttle potentiometer. Randomly found a used pedal at the local BMW breakers, and for the sake of £15 gave it a try. No difference. Got it booked into the local indy on Thursday for a proper diagnostic, but from what I can see online, and talking to people about it, it could all turn into a bit of a farce.

I'd be amazed if it was the throttle body again - already had two and it's knocking on £500 for a new one...