Mondeo TDCi - Uneven power delivery.

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Sat 9 Jun 2007 23:46
Mondeo TDCi - Uneven power delivery. - espzetec
Having a few problems with this car now. 52 plate with 115k on clock.
Basically, when accelerating i get a loud hiss from under the car. can't see any split hoses though? Looked at hoses around intercooler and near turbo and fail to see any splits/holes? any other ideas?

Its been running like this now for about 20k.

The next problem has started today. Changed the oil (which may not have anything to do with the problem) but now i have a problem when accelerating at motorway speeds. For example, when i hit 2800RPM in fifth i get a feeling that power fails and then returns. All fine and good but now it will happily pull till 2800RPM and then it feels like i have my foot on the brake. Other times it lets me accelerate to over 100mph (on a private test road) but them when i get past 100 the power is lost again.

I notice if i press the accelerator very lightly i can sometimes tease the car to accelerate. This problem nearly left me humiliated as power level dropped and i actually ended going slower than the car in the slow lane (how embarrassing!). Problem most noticeable when going up hill....

Any help appreciated.

Subject elaborated upon - PU
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Sun 10 Jun 2007 01:56
Mondeo TDCi - Uneven power delivery. - cheddar
Hissing sounds like an air leak, do you get any dash lights illuminating?

Trip to dealer or indy with relevant dignostics.
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Sun 10 Jun 2007 10:22
Mondeo TDCi - Uneven power delivery. - espzetec
No dash lights what so ever.
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Sun 10 Jun 2007 13:13
Mondeo TDCi - Uneven power delivery. - Quinny100
Its sounds like classic symptoms of a slightly split hose where the hole only opens up as the turbo is working hard. These can be difficult to spot. Get someone to rev the engine as you feel the hoses in the engine bay to try and identify the leak.
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Sun 10 Jun 2007 23:39
Mondeo TDCi - Uneven power delivery. - kithmo
Check the intercooler itself for leaks, if it's been doing it for 20k miles there will probably be some oily residue where the leak is if it's leaking.
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Mon 11 Jun 2007 11:26
Mondeo TDCi - Uneven power delivery. - rtj70
My Mondeo TDCi had symptoms similar to what you describe. I thought it was a slightly slipping clutch but when I took it in the dealer said they'd found a fuel leak (not sure which bit of the system mind). Took it out for a test drive and still the same... Took it back and went for a test drive with the lead technician and he confirmed it was a slipping clutch.

The symptoms for me were you'd be accelerating and for a moment it was as if you lifted off the accelerator and then all fine again. Which is why I thought clutch.
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Tue 12 Jun 2007 16:58
Mondeo TDCi - Uneven power delivery. - espzetec
if it was a slipping clutch, i am sure that the engine would rev freely with no gain in speed. This does not happen with mine so fairly confident its not the clutch.
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