EML and limp mode

HI, my car has a leaking water pump which i assume was the clattering noise i had been hearing as mentioned in previous posts, and it is booked in for a new timing belt, water pump and all other pullys on the timing belt array next Thursday, i haven't used it much since i found out i was leaking water and have been making sure the header tank is frequently topped up, however, today i needed to do a short 20 mile round trip for an appointment and when i started the car the engine management light came on, i checked all the fluids were ok and cautiously drove to my appointment, however it was obvious that i was in limp mode but the light only came on when my foot was on the accelerator and went out all the time that the clutch was in or when i wasn't touching the accelerator but it would come straight back on when i accelerated, this went on until i was just about to park and the light went out and the problem has gone for now, when i got back home i plugged lexia into my car but nothing much came up, there were 2 injector faults but they were P0500: vehicle speed signal speed received by CAN incorrect and P0221: Accelerator pedal 1 signal coherence with the 2 accelerator pedal signal, these codes dont really sound like they would cause the eml to come on but i tried clearing them and the system asked me to enter the mileage and validate, however it would say that it was erasing the faults but after it had finished it said that the faults remain, please could i have some of your wonderful input as i feel out of my depth here, thanks

Hi samstagmoonyham

My suspicion would be the accelerator pedal, it's throwing up codes and it would put the EML on.

Difficult to prove other than swapping for a known good one.

The accelerator pedal has two sensor, if one fails the two signals don't agree and that's what generates the error. Because the ECU doesn't know which signal is faulty it will go into limp mode as a safety feature.

Missing Lincs wrote:My suspicion would be the accelerator pedal, it's throwing up codes and it would put the EML on.

Its does on the petrol, so I would say its the same on a diesel. Unplug the TPS connection (throttle pedal) and reconnect it, then clear all the codes again. If its still bad, click this link to find another TPS quite cheaply on ebay.

Thanks for your replies guys, would it be a good idea for me to spray the tps socket with brake cleaner or wd40 or literally just take it out and put it back in? i guess if the sensor works properly i should be able to clear the codes? as at the moment when i erase them it says they are still there like its a permanent problem even though its gone back to being ok at the moment,
and if its still not working is there a specific pedal for the 8hy engine or is it the same as the standard 8v HDI and other fly by wire c3's? it looks the same to me but i'm not sure.

It could be a wiring/connector issue. I would avoid WD40 and other non-electrical products on the connector. WD40 and similar products are by design penetrating and can get to places where they will make things worse. No harm in using an electrical contact cleaner, however just a simple examination to check for obvious corrosion and any loose contacts, plus unplug a couple of times should tell you if it's the connector.

Missing Lincs wrote:I would avoid WD40 and other non-electrical products on the connector.

Yes, just remove the connector and reconnect it. I have tried this on a similar fault and it cleared, so it worth a try.

samstagmoonyham wrote: is there a specific pedal for the 8hy engine or is it the same as the standard 8v HDI and other fly by wire c3's?

They are all the same, even the petrol engines that are fly-by-wire have the same pedal (yes, I swapped them over from petrol to diesel and diesel to petrol and they both worked fine). 2002-2005 use the same pedal. I have not looked for 2006-2009 yet.

This is a topic I did on an issue with a TPS, you can't open them up very much and it can be much easier to just get another one.
citroen-c3-tips/accelerator-pedal-throt ... t1086.html

And this is a TPS copy fault by Arfur Dent with some lexia diagnostic screens
petrol-c3/1-4-mil-limp-mode-shows-p1161 ... t1133.html

i removed the pedal today and gave both the socket and the plug a good coat of brake cleaner and installed the socket and removed it a couple of times as you said, re scanned with lexia, cleared the fault codes and scanned again to check if they came back with the engine on, i got no injector faults on the global test this time, so thank you very much for all your help guys, a simple fix, i guess maybe the connector was just a bit damp, to be expected in this cold weather i guess