Help!

[Huxley vRS]

Ok so its not my fabia thats broken its my Girlfriends Polo 6n2 Gti but i have to go in my car each night to give her a jump start so help me fix her car to save my car hassle lol.

We had a new alternator and battery fitted 6 - 7 weeks ago... been fine up until about 1 week ago where she had to start giving mild revs to get it start. A couple of times now its been to the point where even this isnt working so I go with jump leads and straight away it fires up.

Strange thing to add is that it was left all night this morning about 11am she started it with mild revving, went to work did her 8 hour shift and then got back to the car and nothing... why did it start in the morning after a longer period of been stood but not after just 8 hours? Again i had to go and jump it and it fired straight up.

Its on 70k FSH and we last serviced it 3 - 4 weeks ago if that.

Any ideas?

PS thought id ask on her because there are some geniuses amongst us lol

[Mike B]

Dunno if it's the same set up as later VAG's, But, Alternator sense wire?

[Mike B]

A scan would help pinpoint the problem!

[Huxley vRS]

Would that cause it not to start without the aid of rev or jump leads? its blagging my head

[Mike B]

Broken sense wire stops the battery charging at lower revs, Slow depletion of charge!

A scan would help, Otherwise it's all conjecture!

[Huxley vRS]

That makes sense. I need to see if the polo has one and where it is.

[Tech1e]

It will have one, does the battery light come on with the ignition?

Should be a two pin plug on the alternator, this will end up going to the ECU, need to see a wiring diagram though to know if there are any other plugs in the system.

[Huxley vRS]

I will check the battery light tomorrow and look under the bonnet for any signs of wear to this wire. I will feed back.

[Huxley vRS]

Anyone got etka and would care to see if there is anything for the wiring to the alterpotato?

[Huxley vRS]

Ok been out to check the car today.

When ignition is turned all the way the battery light comes on and stays on, there are two other lights that also come on and stay on EPC and check ECU.

This morning started without revving my girlfriend went to the shopping centre and spent about 1.5 hours there come back to car and had to rev it a lot to get it started then she drove to the super market and kept it at high revs all the way, after spending 30 mins inside the super market she came out and car started without revving.

Just one thing I forgot to mention the car has been decatted for almost 2 years.

[Huxley vRS]

Quick google search and it seems it could be a faulty brake pedal s/w. If this is faulty it will basically cause the engine to not get enuf fuel when it needs it... Mmm

[Huxley vRS]

Also the searches are basically saying the check ECU light is because a code has been logged as the EPC has been triggered by a likely brake pedal s/w. Looks like its a very common fault on the Polos.

Think I will get the s/w changed and disconnect battery for 1 hour to reset ECU and see where I go from there.

[Huxley vRS]

This has just caught my eye and thrown a spanner in the works.

"did the brakes feel funny as pressing very hard to stop,as the hose u describe sounds like the brake booster/servo hose which does fail on early vws and air would leak into engine affecting tickover and running smoothly.i would have said it would have put an engine light on in dash"

The above would make your brake system use vacuum from the engine which would explain why she has to rev to start?

Her brake pedal has not felt right for a while, you have to press on pretty hard before getting the car to stop even after new pads, I just thought this was because I was used to my bigger brakes on the Fabia

Edited 21 January, 2012 by HuxleyVRS

[national]

It starts when you go start it

Is she Pressing the accelorator before turning the ignition or something ?

National

[Mike B]

http://briskoda.net/forums/topic/74720-list-of-vag-com-diagnostic-system-vcds-owners/

[Huxley vRS]

No accelerator unless it doesn't start

Edited 21 January, 2012 by HuxleyVRS

[Huxley vRS]

Took the car to PSI Tuning this morning to have VCDS plugged in and it found an immobiliser fault so they called me up and basically its the battery at fault it has got enough amps so took the battery back to where it came from and paid an extra £9 to go from the 320amp to 420amp. Seems to be running perfectly.

Booked it in for brake fluid change and check up on Friday to see why the pedal is... useless.