Audi A4 Not Starting-Help Please

[155V6]

Father_155 has just bought a T reg Audi A4 to replace his Renault 25.The Audi has been sitting for a while & has a couple of issues,the battery was flat & the key is broken.He fitted a new battery on Friday & got it running,but it won't start today.

The key is broken,the part that fits into the ignition has come adrift.You can put it into the ignition & it'll turn over & run for about 1 second,but that's it.

I'm thinking it may be some kind of immobiliser problem but not really sure,he said it was running on Friday with the key in 2 pieces so maybe it's something else.

Any advice is appreciated,the bloke who's drive it's sat on wants it gone quick as it belonged to someone else.It's a 1.8 petrol.              Cheers,Tim.

[SiC]

I seem to remember that being a VAG thing where the immo doesn't stop the car starting, but it stops it from continuing to run. Is there any lights flashing or not that light when the engine stops?

[155V6]

Not sure,we're not with the car at the moment but going back again this afternoon.Would that be anything to do with the broken key?

[Tamworthbay]

I had this on our old Passat, it was the fuel pump relay. I can't remember the exact details, but something was bypasssed when the key was in the position for turning over but not when in the normal on position (usually position 1 and 2 iirc). We jerry rigged it with a wire and switch and then all was sorted when I replaced the relay. It was a long time ago but the car is a W plate so similar era.

[plumbertony]

The immobiliser chip is in the plastic body of the key, if the body is held next to the ignition when cranking it should start and keep running until turned off.

I think.

[Ghosty]

Why the hell would you replace an R25 with an A4?

[Dave_Q]

Definitely sounds immobiliser related, ISTR the immobiliser light is a car silhouette with a key on it.

 

This should flash up when you turn it on but go out immediately, if it stays on the chip is not being detected. 

 

You need to try and keep the plastic key body close to the ignition so the chip is detected. 

 

If this does not work try splitting the plastic key body to check it still has a chip in - the chip is a glass looking pill about 2.5mm x 10mm.

[155V6]

Because silly Dad who doesn't keep on top of repairs that need doing,then suddenly finds he hasn't got a working car & buys the 1st thing that comes along   .

[djimbob]

The immobiliser chip is in the plastic body of the key, if the body is held next to the ignition when cranking it should start and keep running until turned off.

I think.

 

I think this is the correct answer, as Dave Q says too, just the metal part of the key turning is not enough, the chip embedded inside the plastic part of the key needs to be right next to the ignition barrel, in exactly the right spot, or you will get what you got!

 

If you look on youtube there are some fixes for this, I would say carefully splitting the plastic body in two with a stanley knife, then extract the little chip, which you then tape/superglue to the ignition in the correct place (trial and error until you find it), then stump up for a replacement key asap is the way to go at the side of the road

 

Best of luck anyhoo

[155V6]

Thanks for the replies,off to have another go soon.Taking a tow rope just in case.

[155V6]

Well,no luck there.The immobiliser light stayed on whatever we did with the fob so it still won't start.Dad says he knows of a place locally who can cut a key & program it to the broken one,so he's going to try that tomorrow.

[plumbertony]

Bugger