Hardstart hot cold ok

Hahn does have a little oil cut off switch. The engine will not start if it is low and oil fill it and try it

www.youtube.com/watch?v=yFSCVgjeV7o 2008 Audi A4 2 0 High Pressure Fuel Pump Failure try to check if there is no fuel leaking from the vacuum pipe

not sure what that means.
lets start over.
your saying car runs great, cold then hot.
then hard to restart a hot engine, right?
the light thing i dont understand
first off, when you stall and engine or just key ON.
the lamps all self test (read the operators guide there)
this is only a lamp test.
odd, the most important is skipped the CEL, check engine light.
is the engine stalling?
hot restarts, fails are: many.

1. injector leaking at shut down.
2. ECT reads to cold when hot. can be below caused
3. Engine thermostat stuck open and restarts are over rich and floods. that hot engine must be at 180F or more,
4. never did a 60,000 mile tuneup this decade?
5. Fuel pressure too high.

i do tune ups first.
then check coolant temperatures, hot. 180F min, and holding or i kick the thermostat to the curb (new stat time)
if it sill dont want to hot start
out comes the scan tool
i scan it, got DTC errors.
is ECT reading 180F ? or above?

that is start on diagnosis.

runs hot,ok, restarts hot ok
just dont start , cold, but it must because how do you get to 2hours?
from hot?
my guess, is it sometimes does start cold.
ever tune it up at the critical 60k mile service, ever, this decade?
that covers 99% bad cold starts. so , we do that first.
diagnosis is like 10x a tune up, so........ $$$$$

hot engine or cold, or both? 180F+ is hot.
Shuts off, idling or on the fly, say at 30mph right foot down it dies?
just clue here...
engine stalls. is complex. but in the macro its below, using tools finds the reason,, but you never said did it restart easy./??????
1: lost of engine compression hot engine, (or overheated)
2: lost 12vdc electric power at stall (caused it) dash goes dead. ?
3: lost spark, test spark at the failure point. if dead trouble shoot speak.
4 bad fueling, too lean (say the fuel pump dies) or too rich.
too rich causes wet spark plug tips. (lots of causes )
5: stalls due to idle RPM too low, below 800 is too low.
too low idle rpm is caused by many things, but top 2 are.
A: EGR stuck wide open, clean it, as the books shows at 60k miles
B: ISC stuck closed. (same deal clean it)

now repost and say when it stalled,
at a read light or flying up a hill wot, wot= wide open throttle.
and when it dies, is the restart easy or hard.

It's not your battery. It might be your IAC valve (intake air control valve) or an EGR valve, maybe even a vacuum leak. The battery is fine. Your fuel filter is most likely fine. When the fuel filter plugs, the car will usualy idle ok but will lose power during acceleration.

check injectors for leakage when engine off-will have to install fuel press gauge run engine and check press ,turn off engine and whatch gauge -see how long it takes for press to drop,will cause hardstart hot engine-but should start better cold

probly o2 sensor, cus when cold the computer does not take into account what the o2 sensor is relaying, but when it is hot it does, try unplugging it when hot and see how it runs, it will run rich but should run ok, if it does its the o2 sensor

Check you Mas Air Flow sensor or MAP sensor.