So I've had a busy weekend with the A4 - cleaning EGR, changing injectors and such like - but it seems I now have a completely different and I think unrelated problem.

After been smug with myself yesterday for curing a very lumpy tickover, the car would not start this morning.

When I turned the key the starter motor operated but it was like it was not engaging with the flywheel - tried it several times, occasionally it sounded to engage with the flywheel for a second or so then I would just hear the starter turning.

 

This went on for 20 minutes - eventually it fired up and ran faultlessly.  

Does this sound like the starter motor shaft not extending far enough?

 

Mark 

 

 

Hi Mark this could well be the Issue, have you got the equipment in order to run a diag on the car to see if it picks anything up first? sensor not responding with ECU possibly? I'm not the best to answer this though.

Hopefully someone with more experience in this will be able to help :)

Regards

Bradley

Hi Bradley

 

I have full VCDS, however there is no fault code generated.

I also seem to remember that the starter on a B7 is not the easiest thing to get to.

I have tried to start it a couple of times earlier today (while engine still hot) and it was ok - lets see what happens when I try later tonight on a totally cold car.

 

Mark

 

Spark plugs at all?

Hello Mark,

One question I would ask is how old is the battery, and have you had it checked for efficiency? I ask since it might reluctantly give just enough umph to (reluctantly) engage the starter motor and indeed turn the engine over, but the residual voltage may be so low - even around 10 volts- that the car may not start. I'm not saying it is this, but I would eliminate this first.

OK, battery may be newish, but there does seem to be a higher proportion of early failures on batteries than there used to be. 

Good luck n getting it sorted.

Kind regards,

Gareth.

1 hour ago, Brad-B5 said:

Spark plugs at all?

Diesel !

 

Hi Gareth

Battery is new - well, 3 months old! - I understand your theory of a potential duff battery, I had it with my Quattro turbo - It span the engine, but JUST not quite quick enough for it to start.

This however just sounds like the starter spinning on its own - I doubt there are missing teeth on the flywheel - otherwise it would never have started - the car is 2005 and has done nearly 250K miles, so it should kind of be expected. Possibly all the grease/lubrication has dried out.

Might try and see if I can get underneath and squirt a WD40 like fluid in it to see if it helps - I don't have the 2 hrs to remove it right now!!

 

Mark

 

Thanks Mark.

Got a better understanding now, which is starter spins but does not engage, rather than engages but does not turn the engine over to start the car. I think we are on the same lines here of the starter pinion possibly not throwing along the shaft and engaging with the flywheel teeth. I would not have thought that the flywheel teeth are the issue here since you would expect some grinding noises as the pinion tries to engage the worn teeth. 

Of course, keep in mind a now sub serviceable starter motor where it does not actually spin fast enough to throw the pinion enough. 

Kind regards,

Gareth.

Have a good look at the earths in the car, particularly from engine to chassis. Make sure they are not loose or looking frayed or corroded.

Hi Gareth,

You've got the jist of what I am talking about - It wouldn't start again last night(20 mins) and this morning (10 mins) just making the same old whirring noise with the very occasional clunk of it meshing with the flywheel for a split second before stopping.

Had a mechanic mate have a listen to it last night - he is convinced its a tired starter motor.

 

Going to get one ordered and get the garage next door to work to put it on - I would do it but I just don't have the time.

 

Dan, - good point! - I'll have a look around later

 

thanks guys

 

Mark

 

 

So, got the starter motor put on by a tame spanner monkey yesterday - what a difference!

you can just tell by the sound of the new starter that the old one must have been totally shot - car starts within a second of turning the key, unlike the 3 seconds previously.

Not had chance to see the old unit yet - i'll try and get to see what state it was in tomorrow.

 

Mark

Pleased you have it sorted!! 👍