Hi

 

I've got a W reg octavia 1.9 tdi that's got an intermittent starting fault. Sometimes it starts first time and once i park up it may not start again.  The alternator is turning but the needles and LED displays on the console go all weird when i try starting it.  I've noticed when the key is turned once, sometimes the ABS light comes on randomly.  Also sometimes when driving the ABS and Hand Brake light comes on. I don't think it's the battery as the car does sometimes start first time without any delay. I don't think it's a timing chain/cam belt issue because the car seems to drive fine and smooth. I would really appreciate any suggestions.  

 

Thanks

 

 

 

Checked all your earthing straps?

109 relay? When it goes wrong everything can go wonky.

Sent from my Nexus 4 using Tapatalk

Checked all your earthing straps?

Don't suppose you have any links for diagrams where those are?

109 relay? When it goes wrong everything can go wonky.

Sent from my Nexus 4 using Tapatalk

Cheers.  I was thinking it may be a relay problem, but wasn't sure which one.

Cheers. I was thinking it may be a relay problem, but wasn't sure which one.

Helpfully the 109 relay has "109" printed on it. Less helpfully if you go into a dealer and ask for a 109 relay they stare at you like you have two heads, as technically its called something completely different. Should be about £15 for a new one.

Sent from my Nexus 4 using Tapatalk

I came across this in another forum and was wondering if this could also be the issue i'm having?:

"The problem appears to be quite common and can be caused by the engine "mapping" which does not allow fuel through to the engine when hot unless the starter motor is turning the engine over at over 250 rpm.

As the battery and starter begin to wear...the starting speed reduces and hence you get difficulties starting (only when hot though?!!!?).

Several forums have detailed wiring in a switch to turn off the temperature sender temporarily, when starting from hot... which basically fools the car into thinking it's engine is cold and hey presto it starts first time."

 

Does anyone have a link to this switch?  is it home-made or can it be bought?

Try unplugging the coolant temp sensor and see if the problem stops. Does basically the same as fitting a switch.

Sent from my Nexus 4 using Tapatalk