Tuscan1969

Hi Again Everyone, Thanks for the advice / thoughts....just to add some more info. - the water temp sensor was replaced but has made no difference (NB the oil temp is ALLWAYS low and seems to take a long time to get towards the middle reading....is this sensor worth changing?) - no fault codes are logged and - I have tried hydraulic lifter additive to no avail. As my car is the petrol model I dont think there is a EGR to change (isn't that only on turbo cars?) Any other thoughts....... Many thanks for your help...

Hi All, My 2004 C5 2.0 SX petrol is garaged over night but still hates the cold weather. It allways starts fine but within 30 seconds the idle slows right down and the car runs rough - it will frequently stall and trigger the catalyst and anti pollution failure lights (although I know there is in fact nothing wrong with these as the warnings go off later the same day once the car has been driven around enough and is properly warm.) .....so whats the problem guys? Is there some faulty sensor somewhere (the garage can't find one but they are not a citroen sepcialist so their diagnostics may not log all faults?) Any ideas gratefully recieved..... PS it had a full service inc filters and plugs etc only 1000 miles ago and its only covered 54K...

Many thanks for the advice - I'll try that! As its just got through the MOT I'll hang on till its ready for scrap!

Hi There – I hope that you can help. My 2003 C5 2.0 16V SX manual petrol (showing about 50K miles) frequently displays the catalytic failure and anti-pollution failure modes….these come and eventually go so I don’t intend to do anything about them at the moment. Similarly I have the fault in the COMM 2000 module that leads to the airbag fault warning but I am prepared to live with that too. However recently it has been acting up in a different way. Immediate starting from cold the car is fine. However within a few yards of setting off it begins to run very rough. Water temp begins to rise but the oil temp stays low and then most time the catalyst fault gets displayed. The rough running gets progressively worse for the first 5 minutes and will occasionally result in the car cutting out when the clutch is fully depressed. The car will re-start easily but still runs very rough and the failure light stays on. The water temp seems fine but the oil temp gauge is very slow to move up and never seems to get to the mid-point properly. As the engine full warms through the running gets a bit better (and if it’s a long enough run it ends up running fine but the warning light stays on). Starting again later on with the engine still partially warm the car is usually fine. It’s recently been fully serviced and all filters etc were changed. It does not do this every day but its noticeably worse in cold and/or damp weather. Yet on a recent long motorway run it performed perfectly. I am hoping its something relatively small like a faulty Oil temp gauge, or maybe just replace the fuel filter. I use the car mainly on short runs (my commute is only about 5 miles) so does the engine need a flush – or is it something more fundamental – I have seen that there may be cold weather starting problems if the air pump is faulty???? Any help is much appreciated. PS for the last two days when I leave the car the suspension has dropped completely flat but only at the back of the car not the front - it levels back up when I open the car but I have had it for 3 years and its never done this before....whats up???? Cheers Tuscan1969