Newbie with an intermittent fault

[overscan]

 

Hi, I'm a newbie on the forum and was until a few months ago a very happy owner of a 2012 Superb II Greenline Estate. Alas, now the car is exhibiting an intermittent fault that neither I nor our local Skoda dealer can get to the bottom of. Hopefully someone has seen this before and can give some pointers. 

 

So, the problem is that the car randomly does not start. When the problem occurs, you follow the normal starting procedure (neutral, clutch down, turn ignition) and all the lights go out on the dash. We did get the RAC out on one occasion and the RAC report said "No feed to starter solenoid exciter. Suspected clutch sensor failure." So we took the car to a local garage and had the clutch sensor replaced, but within a few days the problem recurred. The start-stop engine functionality works fine, so I'm pretty sure that the clutch sensor wasn't actually at fault. I did wonder if it was a dodgy key, but the problem occurs regardless of which key I use.

 

Since then it's visited our local skoda dealer twice. On the first occasion they diagnosed a loose cable and sorted that for free. The 2nd time they said that there were no errors in the ecu and they could not reproduce the fault (sods law with an intermittent fault) and did not charge us.

 

I've got a bluetooth odb2 dongle and no faults show up in carista. I did wonder if it was a sticky solenoid, but then the RAC said there was no feed to the exciter.

 

And the strangest thing is my wife discovered a way to get the car started. Take the key out of the ignition. Put the car into neutral and push (or roll) it a few inches. Handbrake back on and hey presto, starts normally.

 

I've pasted a link below to the most boring youtube video ever.. our car not starting

https://youtu.be/0heXmfi13A4

 

So, I'm crossing my fingers and hoping that someone has seen something like this before.

 

Michael

[StuartTunstall]

Mmmmmm. .. if you move the car a few inches that suggests maybe a few teeth missing or worn from the flywheel.. by moving forward the flywheel will turn a little allowing the starter to mesh..

Does it just spin when it fails to start?..

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[overscan]

Mmmmmm. .. if you move the car a few inches that suggests maybe a few teeth missing or worn from the flywheel.. by moving forward the flywheel will turn a little allowing the starter to mesh..

Does it just spin when it fails to start?..

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Thanks for the reply.

 

No, when the fault occurs there's no power going to the starter according to the RAC. So literally nothing happens.

 

Michael

[StuartTunstall]

Very strange, that rules that out then... the only other suggestion is that the starter is sticking, if this happens, as far as I know all you will get is a "click" moving the car with again move the flywheel and the starter gear freeing it up... so it will start.. 

 

I can't see how moving would fix any form of wiring or electrical issue.. :(

[overscan]

Very strange, that rules that out then... the only other suggestion is that the starter is sticking, if this happens, as far as I know all you will get is a "click" moving the car with again move the flywheel and the starter gear freeing it up... so it will start.. 

 

I can't see how moving would fix any form of wiring or electrical issue.. :(

Yes, I did think about the starter but there's definitely no 'click' :-(

[overscan]

... and it get's weirder. Fault occurred again today. I'd stopped for a couple of minutes to buy some lunch. Like an idiot I parked with the nose facing up hill and sods law the car wouldn't start when I came back. Tried the ignition a couple of times with no luck. Then, just for the hell of it I opened the driver side door and closed it again. Tried the ignition again and hey presto, it starts!?!?! 

[supersnail]

Sounds very much like the starter motor  solonoid sticking to me. Ihad similar with an old renault camper van, I used to welt the starter with a hammer when it happened! If it is the solonoid sticking that would be why there is no feed to the starter and yes slamming a door could be enough to free it, hope this helps.

[supersnail]

Check the low amp feed to the solonoid as well if thats loose can have same effect

[bigjohn]

Just in case it's a clue. Opening the door can fire the tank fuel pump into life.

 

Don't know why lights would go off on dash. Could be a good old fashioned fault such as bad earth

[Sbis]

+1 to a loose earth. Had exactly this problem on an older car. Realised I was just remaking the connection by rocking the car.

Sure Skoda would've picked up a loose connection worth checking. Putting a second nut on to prevent the connection working loose permanently sorted it.

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[overscan]

Thanks for the tips :-)

[peterposh]

The earth from engine to body