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Hi Guys, please help me save my car!

2000 hdi90 rhy engine 230k miles

Intermittent P0220 and p0120 throttle position sensor codes and associated limp mode.
I have changed the tps with a second hand unit from a known good source, no change.
I have checked the 4 wires for continuity from the tps to the ecu, while flexing the cable loom in various places, all good.

Being an electronics engineer I doubt the issue lies with the ecu, so I am reluctant to throw money at that.

I believe an ecu change involves more than just that?

The car is a bit tatty but I've had it 8 years and maintained it well, but I guess if fixed it's still only worth a few hundred quid.

Any ideas would be very gratefully received

Tony

If you disconnect the cable and turn the TPS does it feel grainy?

I had frequent TPS problems on my HDi 90 and it turned out -- after many replacements -- that the solution was to clean out the TPS.

Here's what's inside

Using the fault codes on the search here it also brings up these coupled with MAF sensor faults. Not sure if that's because your code reader isn't picking them up (generic code reader is generic) or what, causes seem to be said MAF sensor and, oh lord, burned tracks inside the ecu

I think changing the ecu does involve changing the BSI too but I'm not sure if this is solely for the mileage issue (which I don't think you'll worry about) or if there's more to it (matched for life?)

Did you manage to clear the faults and did they come straight back?

Thanks for the reply guys.

codes were read (and cleared) by a Snap-On reader, also checked tps action and it was fine. Stayed clear for a couple of weeks. Fault has become worse ( more frequent) over time, getting noticeably worse when I pulled the connectors apart to check continuity between ecu and tps.

I might just run two fresh signal wires from the tps to ecu temporarily to rule the wiring out. Might try the snap on reader again. In my mind if the problem is the ecu then the car is scrap.

Found a path to ground on one of the wires from tps to ecu. Replaced wire and it now seems fine. fingers crossed.

Excellent work
Thanks for reporting success.

Yes indeed, nicely done. Did you manage to find where the damage was or did you just run new wires and job done?

Well done.

I didn't look for damage, was worried that that would cause more harm than good! Still running fine.

Tony