a4 tdi 130 wont start when hot ,

[160tim]

My 54 reg,avx engine code,a4 wont start when hot.It will run all day long,but if i stop the engine for about 10 mins it wont start again.If i crank it over,for what seems like ages it sputters into life and runs perfectly.A couple of times i ran the battery flat and had to crank it from another car with its engine running.This has now stopped me using my car as i'm sure the starter motor will burn out soon or the battery go flat again with no one around to help.I've plugged in my laptop ,VAG COM shows no faults.PLEASE HELP
Forgot to say,if left over night car starts first time every time with just a flick of the key.Just started the car today after two weeks sat on drive,started first time as usual.Left it warm up (1 hour), switched off for 10 mins,won't start !!!
If you could help solve my problem i'll FIX YOUR PLUMBING FOR FREE

[Mojocvh]

Well. That is a bit different.

So what affects the fuel system or injection, when hot to stop a oil burner starting.

Surely not the engine going tight?

Can it lose enough comp to prevent a start when hot?

Map signal screwing up due to heat affecting it?? But no codes.

Knackerd temp sensor??? but surely the ecu [once it's at running temp] wont trim fuel any "less".

Is the starter mechanically engaging to turn the engine ?/ Must be-too obvious.

Heat. gotta be heat related.


Damn and I've got a dicky boiler too.

[TDIfurby]

Firstly I would check the battery. Best way might be to connect the car to another battery via jump leads when it would usually be a bugger to start.

After that, probably the starter motor needs to be replaced.

[160tim]

battery fine,will turn over for ages ,thanks for your input.Tim

[160tim]

Mojocvh said:

Well. That is a bit different.

So what affects the fuel system or injection, when hot to stop a oil burner starting.

Surely not the engine going tight?

Can it lose enough comp to prevent a start when hot?

Map signal screwing up due to heat affecting it?? But no codes.

Knackerd temp sensor??? but surely the ecu [once it's at running temp] wont trim fuel any "less".

Is the starter mechanically engaging to turn the engine ?/ Must be-too obvious.

Heat. gotta be heat related.


Damn and I've got a dicky boiler too.

Thanks for your input. Starter motor is engaging fine and turns engine over until battery is flat!! Tim

[TDIfurby]

Battery might appear strong, but it might simply be slightly under-performing and not achieving the ampage to actually fire the engine into life?

[160tim]

Finally fixed !
Intermittent fuel pump relay,located under ecu £16 from VAG.
Many hours of investigation £ free ,result!
If anyone needs more info or help please contact me as this seems a common problem with this engine,confirmed by the fact that the relay has been given a new part No. and audi had two on the shelf.

[Sweeman]

Very helpful info, Tim. Same scenario with me and Audi service in Dubai has been useless as they never seem to be able to replicate the issue. Can you provide anymore detail on the part number and/or photo of it to help locate it? Much appreciated

[alfro04]

Sweeman said:

Very helpful info, Tim. Same scenario with me and Audi service in Dubai has been useless as they never seem to be able to replicate the issue. Can you provide anymore detail on the part number and/or photo of it to help locate it? Much appreciated

Hi all, i have had this car for 6 years its an audi a4 2.ol 2005 model, bought it used and since i had it its hard to start when is hot.
it has used a couple o bateries, and today i diceded to find out the problem.
Some on point this mechanic to me aparently worked at vw shop for 16 years, he tells me that need reprogramming at the low rpm between 200 and 700 rpm, because the car lost comp. and needs to be boost more at starting.
To me doesnt sound right, if the car is hot, teh chamber is already hot so shoud fire easier...
but i would like to hear from someone more experienced, thanks a lot.