306 intermittant ECU light problme

[tonylds]

Can anyone help me with a problem with my Pug 306. For some time now I’ve had an intermittent problem in that after cruising at speed for about half an hour the car starts jittering (like a misfiring) and the ECU light comes on and off.

After this had been happening on a 2 hour motorway journey I had a new problem when I came off the mway – the car would stall when I took my foot off the gas. I found this was due to the idle valve being completely closed to air. I removed it and slowly, manually pushed it open a bit. After re-fitting it the engine revs were then too high – this brought the ECU light on but it did not adjust engine revs to the programmed idle setting, as I expected it too. I then set the piston so that it was low revs and again it didn’t auto adjust.

As the fully closed problem happened after I’d been having intermittent ECU flashing/jittering problems on the mway I decided to buy a new one.

When I fitted this I again had the same situation ie if the piston wasn’t in the correct position, the ECU did not drive it so that it was.

Can anyone tell me if, when I manually misadjusted (or fitted the new) idle valve it should have auto-set OR if I needed to run the car for some time OR if it needs setting up manually by a garage. I ask this because I have been told these 3 things by different garages and so am looking for more opinions please

I suspected my original idle valve was ok and returned it for a refund (but having doubts again now !!)

I’ve just done more motorway driving and again had the intermittant problem. I took it for a diagnostic test and codes for idle valve and oxygen sensor were logged. I am suspecting that the idle valve codes were recoded when I misadjusted the valve and that the oxygen sensor may be my real problem. However I’ve been told that oxygen sensors rarely fail intermittently like this – and the code could have occurred because of an “unknown” problem – can anyone advise on these points please

Sorry for the essay, but here are the specific questions I’d appreciate answers to

1) should idle valve auto adjust at idle
2) Could an idle valve on a Peugeot cause my intermittent problem when cruising (it did on a corsa I one had)
3) Do oxygen sensors fail intermittently
4) Can other problems apart from the oxygen sensor cause an oxygen sensor code
5) Could oxygen sensor failure cause my jittering problems and could it also have caused the idle valve to close completely as happenend on the journey I mentioned above

As you can tell I’m getting pretty confused here because it seems I may have 2 independent faults but I suspect they are linked

Any help greatly appreciated
Thanks
Tony