faulty fuel pump symptoms

[nazS3]

Hi guys

my s3 amk 2001 has problem starting from cold currently, turns over fine just wont fire
i can hear the pump priming when ign is switched on

got it started for few mins then it cut off again, & wont restart

no fault codes at all, have fuel, have checked/replaced pump relay made no difference
so could it actually be the pump in tank, as car has done 129k now
thanks in advance

 

[<tuffty/>]

Does it do this on a full tank? this normally happens when the tank is half way or less full... pressure drop occurs and takes a turn or two to get it back up enough to fire..

Fuel pump can be tested with a fuel pressure gauge and a dyno... you can also log what fuelling is doing using VCDS to see if the pump is struggling under load/boost as the revs rise...

<tuffty/>

 

[karl210]

Does it do this on a full tank? this normally happens when the tank is half way or less full... pressure drop occurs and takes a turn or two to get it back up enough to fire..

Fuel pump can be tested with a fuel pressure gauge and a dyno... you can also log what fuelling is doing using VCDS to see if the pump is struggling under load/boost as the revs rise...

<tuffty/>

Ive got a feeling my fuel pump is running out of puff at high rpm, what blocks would need to be logged? thanks

 

[nazS3]

to be honest, car has approx tenners worth of fuel in it from empty tank
& is parked on a slight incline driveway, car is currently off rd
so cant fill up

do you think low fuel is the cause, as i have no fault codes & can hear pump priming
could the cts also be a posssibilty ? even though normally if the cts is faulty i would def get a code
& only have problems starting from operating temp

Does it do this on a full tank? this normally happens when the tank is half way or less full... pressure drop occurs and takes a turn or two to get it back up enough to fire..

Fuel pump can be tested with a fuel pressure gauge and a dyno... you can also log what fuelling is doing using VCDS to see if the pump is struggling under load/boost as the revs rise...

<tuffty/>