My car won't start once it's hot
Other than that he run perfectly
Anyone have a idea what it coule be?

What shampoo works better than the one im using?


no idea right?


it helps to know what you are working with.


If the car is an 09 it will be a far different diagnostic path than a 79.

True story bro.

Yeah my bad

1999 audi a6 avant with 1999 4.2 a8 engine and 2004 s4 tranny swap

does it not start at all?

or

does it just take a lot of cranking/nursing to bring it to start?

Because I'd start by checking fuel pressure, and making sure that the fuel pressure regulator is in good working shape, and make sure your injectors are not leaking down either.

If your fuel pressure leaks down after you turn off the engine, that could be leading to harder warm starts.

This is a very good place to start. Is it throwing any check engine codes?

Theres a few since it's a damn swap but nothing related to the engine



If there was a leak wouldn't the engine run roughly?

are those codes from a generic obd2 reader or a vag-com? the generics wont show you everything on audi

also do you know if its getting spark and fuel?

i use a strap-on verus and it show me everything and I assume there spark and fuel cuz I can hear the backfire from the intake lol
It feels like it's getting flooded but how .. Idk lol

Has it done this since the swap? He doesn't mean an actual leak. The fuel rail is supposed to stay pressurized. This allows a near instant start. If the injector is leaking by slightly pressure will drop and the fuel pump has to re-pressurize the fuel line and rail. This will cause a slow start. If the fuel pump is weak it could cause the same problem. He asked how it acts when it starts. That will help a lot. Does it spin and spin and finally start? Does it not want to spin as fast as it does on a cold start? How does it run once it starts? The are several sensors that could cause problems too.