VW TDI Starting noise - matstro
Is there any chance someone can help with a bit of an urgent problem?

We have a Seat Toledo (engine is same as VW TDI 110bhp)year 2000. mileage 95k

When starting the engine, as soon as it fires, there's a awful loud metallic graunching type noise causing severe vibration through the car coming from the engine bay which actually stops the engine running as soon as it fires up. This only happens about once in every 12 starts and on trying to start the engine again everything is fine. When this problem occurs, there is a large amount of smoke from the exhaust.

The car runs fine other than this. We're putting on a new starter this week as also when starting, the starter tends to whine on a bit after the engine fires. Hopefully a new starter will sort this. I was rather assuming the starter was somehow jamming in the ring gear and the horrendus noise was the starter cog mashing against the ring gear. But, the cog doesn't seem unduly worn.

Can the starter jam up inside and effectively stop the engine running?

Any other cause for this worrying noise???!!!

Any help and advice much appreciated.

VW TDI Starting noise - DL
Sounds rather alarming....

The starter (if faulty) could run on and cause a fair old racket, but it wouldn't stop the engine.

Given that it is pulling the engine down, I'd advise you not to operate the car until it has been looked at professionally. It could cost you a lot of money in the long run if it were something critical (cambelt??)
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VW TDI Starting noise - matstro
Thanks DL, yes this noise is alarming!!

We've had a mechanic out this morning who's stripped the engine. The cam belt is well worn (was squeaking on start up) so we'll have a new one, starters off but looks ok.(from the outside) Had a seperate problem where the pulley on the alternator had seized and unscrewed and dropped off the other night (its a freewheeling one) so got a new one of those too. Nothing else seems obviously the cause of this noise. After the last time it happened we decided not to run the car until fixed. Thing is the mechanic is saying its probally the starter, he'll put the new one on and go from there.

If this isn't a starter problem, can anyone hint as to what might be the cause??

The only thing I would say is on the night the alternator pulley dropped off, 30 minutes prior to this happening, this starting noise happened about 6 times (I couldn't get the engine to run. Each time I started it (6 attempts) the noise occurred each time. Finally it started, 30 minutes later the pulley went! Coincedence probally?
VW TDI Starting noise - BB
Starter motors on several of my past VW's and current VR6 suffers from starter motor running on. It si an alarming sound, but I would agree with DL about not causing the engine to stop.

If the new starter motor doesn't cure it, make sure you post back on here so we can look further.
VW TDI Starting noise - none
Does the engine have a dual mass flywheel ? (I think it might have). The noise and rough running can be caused by a faulty flywheel.

VW TDI Starting noise - matstro
For anyone interested, put a new starter motor on as well as a cam belt, tensioner and idlers and the racket on start up seems to have gone.

The new starter sounds really sweet and starts the engine instantly. I still can't beleive it was the old starter causing this problem but seeing as this noise has gone, maybe it was???
VW TDI Starting noise - Peter D
The VW diesel starter employs, as on many diesel cars, an epicyclic gear box which is an extension to the starter motor body to up the torque but drop the revs this is needed to overcome the much high compression ration. If the pre-engage solenoid sticks it leaves the bendix engaged on the flywheel and the engine tries to spin up the starter but the gearbox puts up considerable resistance when driven backwards and it stall the car. I’m surprised it has not bent the starter drive shaft or stripped the teeth.
VW TDI Starting noise - matstro
wow, Peter D what a stunning reply!! The teeth on the starter cog had started to bevel at the end. Seems like that was the problem. Mind is 100% at rest now!!

Many thanks
VW TDI Starting noise - DL
Good result!

Thanks for posting back here on your progress - it's a shame others don't often do the same!
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