2.1 TDi

[smudger110a]

I just dont know where to start with this one,but here goes,Start up no problems,no smoke,but when driving along,say for example,40mph,you dont push the accellarator down and it just picks up speed for NO apparent reason ,take foot off and it does 50mph,60mph,70mph,and then you try and stop it and it wont stop,turn key off,foot on brakes,until it eventually burns the disc's up and cooks the pads,.then when has stopped for a couple of minutes and calmed down,you can carry on sometimes for 1 mile or maybe if you are lucky 10 miles,question is; what is making it do this ? pump? head gasket ? engine itself ?when it is running properly or on first start up,the whole lot is so sweet a runner that you would never know that there is anything wrong with it.i've now gone bald trying to find out what the problem is..it is a 1997 on an "R" reg.Anxiously waiting to see if anybody on here has had a similar problem ?and what it could be.yours frustratingly Ray... sorry forgot to say that it has done a mere 143.000 miles

[Welly]

Bloody hell!

Remember that the only way for a Diesel engine to rev higher is to inject more fuel (since it doesn't have a throttle butterfly) this makes me think that the pump or injectors are a fault, perhaps the fuel return pressure regulator (if it has one?) is sticking and forcing more fuel to be injected - it's supposed to open at low loads to return fuel to ths tank (spill off).

Another more worrying thing is that a diesel engine will go wildly out of control and rev it's nuts off if it can consume it's own engine oil from the sump possible causes are overfilling with oil, blow turbo seals and blocked breathers.

Can't say I've heard of this before on the 406 but hoe the above helps a bit?

Welly.

[mjb]

Another more worrying thing is that a diesel engine will go wildly out of control and rev it's nuts off if it can consume it's own engine oil from the sump

Usually that just means it won't turn off, not that it revs.

What's the throttle pedal connected to on diesels? If it's a pot(entiometer), it could be shot


Smudger: I'm guessing it's an auto - can't you put it in neutral (or at least limit the speed with one of the gear limit settings) instead of frying your brakes? When it's accelerating on its own, is it doing it at full power or is it mild acceleration? Stupid question i know, but you don't have a mat in the footwell that's catching on the pedal (that got me once, gave me the fright of my life!)

[smudger110a]

Thankyou Welton and Mjb,The estate is a manual one,I also think that i need to get a dipstick for the oil as i am unsure wether the one in it is the original one (as it is all taped up on the end) so i think the best course of action at the mo is to give it a fresh service,and go from there.If not then i would rather buy another engine complete because there seems to be too many if's and but's with this problem.I even spoke to Peugeot garage and had them scratching there head.ENGINE ANYBODY ? incase i need one ?I also want a dipstick if anybody got a spare one laying around.how much including post if anybody has ? regards to all, Ray

[Welly]

and then you try and stop it and it wont stop,turn key off,foot on brakes,until it eventually burns the disc's up and cooks the pads

Usually that just means it won't turn off, not that it revs.

If a Diesel has got access to big pot of engine oil it will rev at MAX revs untill it's all gone

[darrenwall]

and then you try and stop it and it wont stop,turn key off,foot on brakes,until it eventually burns the disc's up and cooks the pads

Usually that just means it won't turn off, not that it revs.

If a Diesel has got access to big pot of engine oil it will rev at MAX revs untill it's all gone

or untill it goes BANG

[steve_earwig]

Oh my... I have some bad news for you: your car is possessed. You need to call a priest immidiatly or your soul is toast.

Hmm, sump oil. I'm not sure how the 2.1 cuts off the fuel, there's a stop solenoid on the 1.9 but nothing similar on the 2.1 but I'd guess killing the ignition's supposed to do the trick. Unlčess you suddenly have two faults... I suppose the easiest way to tell is to see what's in your sump, if the level's gone down a whole lot then you know what your engine's running on. The usual cause (on Bimmers and Mundanos) seems to be blown turbo seals I'm afraid. However, if your sump's level's ok then get back to us for some serious head scratching, or alternatively get thee forthwith to an engine management specialist.

I would say you'd be best off not driving it. However, if you really do need to (eg. wife's about to pop, kiddie's broken a leg) remember that dipping the clutch will help in an emergency. True, your engine will self-destruct, but then you can replace it for a few hundred quid, the last I heard the NHS were fresh out of replacement bodies.

[poddack]

Mine did this the first time I started him after an engine replacement, he revved the bollocks off himself and kept on going for a few seconds after removing the key. I ran off shi**ing myself. All went quiet.

I started him up again and he idled normally and has never done it since, in fact he''s fast and very smooth, all I can guess that he was priming himself.

From that I would advise a good service, look for air leaks in the fuel line, a dose of redex.

But then again I could be wrong, just my logical thinking.