Spec me a DMF failure...

monkey_boy · 4 Aug 2010 at 11:33

My sister in law has an 05 plate mondeo TDCI 130. What are the symptoms for diagnosing a failing DMF? What are the implications if it is left for too long and how long does it take to get from going to gone?

Cheers,

iaind · 4 Aug 2010 at 11:57

Rattling, especially on startup - sounds like a bag of nails

Clutch squeal

Starter motor struggling

Hard to say how long it's got, normally the rattle is first but mine started with the squeal. The replacement involved replacing the clutch, so colatteral damage there isnt a concern, but if it's got to the stage where the starter is affected - it's definitely time to sort it. Often the starters can be cleaned, but if its left you can add a new starter onto the bill.

Dont pay more than £700 to sort it

MrKnifey · 4 Aug 2010 at 15:34

If its anything like the VW if it fails in a bad way it can take the gearbox housing and engine housing with it! Dont leave it!

Keyser Soze · 4 Aug 2010 at 19:57

Mine has a horrible tapping/rattling noise at idle, gets worse up to about 1000 rpm, noise gets considerably quieter when you dip the clutch.

car also vibrates at idle, and when turning the engine off seems to shake worse.

hard to notice any difference once moving though.

parts are about £400 and be prepared to be quoted for 6 hours labour on top of that.

Iceman · 4 Aug 2010 at 21:27

Start up/shut down rattle.
Excessive vibration through clutch pedal.
Noises from area.
Rattle when on idle.

*Moangroan* · 4 Aug 2010 at 21:33

As above plus as your pulling away it may kangaroo a bit.

I know on vw they have a little inspection cover. Or remove starter. And see how much the the dmf moves. There is no need to take out transmission to check if you are lucky.

monkey_boy · 4 Aug 2010 at 21:54

Oh cool, that's not so bad then. Her's doesn't seem to have to sort of torx you expect from a diesel from pulling off and pulls quite a way through the rev range. I suppose this is just a different style of power delivery to the way the VAG and BMW diesels seem to do it.

The other thing that got me thinking was that if you dip the clutch at the lights or while you're on the move, the rev counter fluctuates around idle before it finally settles down.

[TW]Fox · 4 Aug 2010 at 21:56

monkey_boy said:
Oh cool, that's not so bad then. Her's doesn't seem to have to sort of torx you expect from a diesel from pulling off

Expectation management could be the issue then. Frankly no 4 pot diesel I have ever driven has 'torx when pulling off'. They've all got a frankly gutless point between idle and about 1600rpm when the turbo begins to come into play when pretty much nothing happens, you can nail the throttle for a second even and it makes no real difference.