Has anyone had the same issue of the car cranking and starting. Then hours later it starts. Need help before I take to dealership. Want to educate myself

 

Sounds like a fuel pump or fuel pump relay

 

Hi, I have the same problem with my A3, it will start and run for days,, then randomly it will crank but wont start,,, i have changed the fuel pump relay but that has not helped,, if i take her out and park up, i never know if she will start again,,, on two occasions while waiting for the AA she started doh! please let me know if you have any joy,, im thinking if there is a fault with the key? as in the code, thanx elle.

 

If it cranks and starts but immediately dies, then its a key. If it cranks but never starts, it is not the key. The A4 as well as A3 are notorious for failing fuel pumps, especially if you live somewhere that gets 90 degrees or higher and you tend to run the tank down to 1/4 or lower. Fuel keeps the pump cool and thus increases it longevity. I would bet since somedays it starts and somedays it doesn't you need a fuel pump. Remeber to always replace the fuel filter when doing the fuel pump to avoid destroying the brang new pump you put in. Let me know if that doesn't work and I can help you did further into the issue.

 

Hello,
I have this same problem on my A4... I took today as a matter of fact to to get inspected and was advised that the relay J271 and J757 needed to be replaced. My A4 does the exact same thing. It will start at times and go weeks without doing it and then all of a sudden wont start. Will wait in the car, try once or twice more and walah it starts after several times.
I wanted to know if I can replace the relays myself. Can anyone advise on this matter?
Help please of how I can replace these two specific relays.

 

Hi, I had the ignition sensor replaced, it seems fine now, but only after replacing the relay and the fuel pump doh!

 

Similar problem on my 2007 A4 3.2. My solution was that my EFI and ECM relays were bad.

 

Hi guys, i have the same problem, if i leave my Audi A4 2.0 TDI for a few days, it cranks for ages before starting. But if i only leave it a day and / or prime the engine multiple times (turn the key, wait, take the key out, etc), then the engine starts fine! Would there be any way of determining whether i should replace the fuel pump, fuel pump relay, ignition sensor, EFI / ECM relays?

​​​​​​Any tips would be hugely appreciated!

 

It was my mechanic who discovered the bad relays. My consumer level code reader couldn't show me anything wrong, but his professional scope showed him immediately that the EFI and ECM relays were bad. Replacing relays is a fairly inexpensive and easy thing once you know that they're failing.

When I was first doing my own troubleshooting, I replaced the fuel pump and filter myself, but it ultimately wasn't the problem.

If you're trying to avoid the mechanic, start with the easiest and cheapest possible fixes -- which are probably the relays and sensors, then move on to more difficult fixes, but you could be wasting money and time. My mechanic bill was $385 for the relays and labor, but I'm glad I'm not on a wild goose chase anymore.

You might be able to find a mechanic that will do the diagnostics only and then you do the actual fix yourself in order to save money.

 

Hi, ok maybe ill replace those relays then, many thanks for the info!

Did you have the same symptoms I'm describing? The car will start absolutely fine, unless you've left it sitting for a few days?

Cheers!