Underfueling and noise from the fuel pump

[spiker]

Hi

engine management light on - Vag com reports underfueling and whine from fuel pump intermittently

Fuel pump changed - noise still there
Maff changed
Thermostat and temp sensor changed
Fuel filter replaced

Still no better

Dis reports 42mpg overall !! which is inaccurate - checked based on last fuel load and was actually getting 29mpg

This has been going on for 6 months now and I know i should just take it to audi ( my local garage is not very s3 friendly ) but i am trying to avoid the dreaded dealer rate

Any suggestions much appreciated

Cheers

 

[Andrew@A.L.D]

Have you checked the fuel pressure?

 

[spiker]

How is that done ?

 

[Andrew@A.L.D]

some of your local fuel injection specialists should be able to help

 

[<tuffty/>]

Could possible be a problem with the fuel pressure regulator (FPR), check the vacuum hose coming off the FPR which is on the right hand side of the injector fuel rail.

Could do with being logged tbh, You are not too far away from Badger 5 (J13 M5)... might be worth giving Bill a call, he would be a lot cheaper than a dealer

<tuffty/>

 

[sportstractor]

was also going to suggest fuel pressure regulator.

Ha my local Audi garage dont seem to be S3 friendly either, they seem fearful of the thing

 

[Welly]

was also going to suggest fuel pressure regulator.

Ha my local Audi garage dont seem to be S3 friendly either, they seem fearful of the thing

Thats because, IMHO, Audi Mechanics know as much, or less than, your average work a day mechanic.

They are the same old bodgers in nice overalls.

 

[Welly]

Could possible be a problem with the fuel pressure regulator (FPR), check the vacuum hose coming off the FPR which is on the right hand side of the injector fuel rail.

Agree. Does the fuel pump still whine, even though it's been replaced?

The FPR being shot would explain the whine of sorts - it is probably being over worked due to fluctuating pressure requirements.

 

[spiker]

Cheers guys - FPR next then

Do you have any contact details for this 'badger' ?

 

[sportstractor]

its badgerbill on this forum

 

[<tuffty/>]

Cheers guys - FPR next then

Do you have any contact details for this 'badger' ?

PM (http://www.audi-sport.net/vb/member.php?4263-badger5) or give him a call...

<tuffty/>

 

[spiker]

The Badger discovered a knackered FPR , replaced the top lambda , fuel filter and blew out the pipes
Strange black residue coated the FPR - which turned powdery when dry - no idea how it i got in there or what it was

So all sorted -

 

[Welly]

The Badger discovered a knackered FPR , replaced the top lambda , fuel filter and blew out the pipes
Strange black residue coated the FPR - which turned powdery when dry - no idea how it i got in there or what it was

So all sorted -

Glad it's sorted, I saw it up there and thought she may have a knackered FPR.

Could be residue from contaminated fuel - there was a big thing a long while back where Tesco sent a batch of fuel out contaminated with Silicone and it shagged a ton of Lambda sensors.

Could be something similar - I've had dodgy fuel before (normally always from Texaco - AVOID!), when emergency filling with sh**ty fuel.

 

[spiker]

I try and avoid supermarket fuel , on the odd occasion i use if i have no choice but usually just to get me to shell

I remember those issues a while back - shame there's nothing I can do about it