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Club XM Forum > Petrol Specific Issues
huh.gif Hi All
Had my CT turbo (in Readers Rides) for a week without any driving problems and in particular it started and ran perfectly as it did this afternoon.
However, this evening I tried it on max ride height to look for source of blowing exhaust. Engine started to vary it's revs and needed throttle to prevent stalling. Management light started flashing; there was a buzzing from under driver's side dash and in the glovebox area, a noise in sync with management light from under rear of car and a clicking
from engine compartment (does not sound like accumulator). I also get a single bleep which may be associated with dot matrix display which is unreadable.
Put car back to normal ride height, switched off and went for cup of tea and good swear.
Tried again 2 hours later and engine reluctant to start especially with g/b in park but will start with difficulty in neutral. Rate of clicking from eng bay reduced but other noises the same. As my driveway is very uneven I regularly use intermediate ride height without problem but today was first use of max height.
The previous owner had the ECU 'wiped' (his words) by a UK company because of starting problems and the keypad although present is out of circuit.
The plipkey still works for both central and deadlocking.
I would be grateful for any pointers as to where to look for problems.
Many thanks
biggrin.gif Hi
It is running again fingers crossed.
The car had not been used for sometime before I bought it. The chap I bought it from had just changed the plugs as he thought there was a
slight misfire. He also said ecu had been taken out, wiped and refitted.
So, I checked HT leads for tightness and generally poked around anything that might have been disturbed during plug change.
Similarly, I had a look at the ecu housing and moved wiring looms slightly. I also noticed that the cover over the front of the big ecu box was not secured properly.
I will have a more detailed look at the cable looms and connectors when weather improves as strangely for southern France in July it has been wet, windy and overcast for 10 days.
Are the Lexia code readers on ebay a good buy at around 90 pounds and do you just need a laptop with Windows xp or earlier to be in business?
I am hoping that the car just needs to be driven regularly to settle down, it certainly runs and rides nicely. Even in this part of France, the XM is a rare sight,
especially petrol engined.
On a different note, I have just got, again off ebay, the sphere removal tool so that I can change my Xantia spheres. Nicely made and a perfect fit.
Best wishes to all. Sean

Hi Sean

Wiped ECU's can sometimes play up.
It makes fault finding very difficult as the only way I have found to check is an ECU swap with a known working car.
If the good ECU works in your car (with keypad in if ECU coded) and the engine runs well then it will be your ECU playing up.
If your ECU also works in the other car then it will be dirty contacts on the ECU and plug.
Be aware that a common cause of contact problems comes from the missuse of Vasaline or similar greases as contact corrosion preventers.
These greases are actually insulators and can make a poor contact open circuit. Use should be restricted to preventing moisture getting to already made connections such as battery terminals.
Just had to replace the wiped ECU in the latest 2.5 because it reverted to red/green when I renewed the underbonnet F2 fuse using a high current fuse and holder.

Hi Sean,i personally have found the Lexia to be a good tool,i do however back up any fault diagnosis with an oscilloscope,but the Lexia hasn't been wrong yet and the big plus with it is you can perform actuator tests both static and dynamic.Yes a good tool.However - there's always a "but" - some of the guys on the forum are having mixed results so do some research on suppliers.
For downloadable manuals including the Haynes engine ECU diagnostic, which gives instruction on how to build ,use and interpret a code reader,and covers your engine code goto and register.
biggrin.gif Hi Robert
Thanks for your reply. What a great site Ebaman is, I had not heard of it before.
Hi John
Many thanks for your reply. Touch wood, car seems to be running OK.
I take it out daily for 14 km round trips ( keeping close to home in case of problems- no AA or the like in France). Starts fine when cold and when warm.
Eng man light comes on with ignition on and goes out and stays out when engine running. Keypad is fitted (complete with unbroken cover) and with ign on shows both red and green which go out when engine running, however, the keypad is not needed to start the car. I know that keypads can be bypassed by disconecting while engine running ( brother's pug 306 ) but then I assume red and green LEDS would not light.
I still have my estate in running order and it needs keypad for starting, but if it's ecu is compatible and I put it in the turbo would it not require the keypad code to work?
I am hoping that initial problems are a function of car not having been driven for a while before I bought it plus my inexperience of automatics.
You will need a and ECU from another turbo to test it with
Hi All
More problems with engine management. Drove 8 kms into town to book exhaust change. Started and ran perfectly from cold. Stopped and started car twice while shopping and again no problems. Started car for return journey no problem but en route noticed that on partial (trailing?) throttle, engine performance at 30-40 mph was 'fluffy' and not smooth. Idled OK at road junctions and under acceleration engine picks up and hesitency disappears.
Got home, switched off engine and tried out one of these FM transmitter gizmos that fit in lighter socket and provide USB and SD slots for music playing etc.
This involved switching on ignition whereupon eng man light flashed at regular rate in sync with a clicking noise which when in the car sounds as if it is coming from the rear but when outside it is from engine bay. There are 2 areas clicking in sync - one from the large housing containing ecus and relays, the other from centre top front of engine (throttle cable) area. Spark plugs are brand new, fuel guage shows half full, no hissing on undoing fuel filler cap. Tried starting 2 hours later, did not start with P selected and but did reluctantly in N and idled fine with no eng man light. Problem seems temperature related and boy the engine bay gets hot! Can anyone point me at specifics other than the normal checks of elect connectors and air leaks? Not sure if turbo is working but that is for another day. Coolant level and temp OK. Many thanks, Sean
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