XM 2.5 td Power loss uphill

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leocitroen
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XM 2.5 td Power loss uphill

Unread post by leocitroen »

Hi,
When I drive XM it seems to me that the car goes very well, strength is satisfactory. But when I get on the uphill car lost power and as much hard I push gas pedal car does not accelerate. When I get to the top of the climb because I pressed the accelerator almost to the end, the car gets full power and rapidly accelerate.
Any suggestions welcome.
Peter.N.
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Re: XM 2.5 td Power loss uphill

Unread post by Peter.N. »

Sounds as though the turbo is not working or at least not properly, check the hoses to and from the intercooler for splits or poor fitting.

Peter
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Mandrake
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Re: XM 2.5 td Power loss uphill

Unread post by Mandrake »

leocitroen wrote:Hi,
When I drive XM it seems to me that the car goes very well, strength is satisfactory. But when I get on the uphill car lost power and as much hard I push gas pedal car does not accelerate. When I get to the top of the climb because I pressed the accelerator almost to the end, the car gets full power and rapidly accelerate.
Any suggestions welcome.
If you're certain that you have full power when the car is on a level surface and that it loses most of its power on a gradient I would be checking the in tank fuel pump (if it has one) and the in tank filter sock to make sure it is not clogged up. Also check the fuel line from the tank to the injector pump for air leaks. (Only applicable is there is no in-tank pump)
Simon

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white exec
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Re: XM 2.5 td Power loss uphill

Unread post by white exec »

There's no in-tank pump, but the tank suction pipe can get grot around its lower end. Vague recollection about the suction pipe being very close to the 'polythene' tank bottom, and able to suck it up and restrict the supply. Not a common fault, and not sure whether it applies to the 2.5.

Also check
- there's no undue slack in the throttle cable, where it meets up with the accelerator potentiometer in the engine bay. Slack should be a minimum; make sure the adjusting clips are in place on the cable outer, at the bracket.
- the fuel filter isn't clogged; replaceable Purflux paper element, and an internal micro-fine bronze filter behind the filter head output banjo.
- fuel tank is properly vented; try driving with fuel cap slackened. Possible fault, but unlikely.
- accelerator potentiometer at fault - check with Lexia and ohmmeter; normally a reliable item - so engine ECU does not know how far the throttle is open.
- connection or wiring fault to the engine ECU (unplug and contact clean the 55-pin ECU connector).

Lexia would reveal recurrent faults.
Chris