S3 fuel issues

[Pedrosousa]

I'm having some problems with fuel, first the car takes to much time to turn on when it's park for a night or some days... (some times I have to do a second try to start it) Second in my remap, with LAMFA or KFLBTS I can only get 13.3 of AFR...

Can I use this in the S3:

Walbro 255 LPH GSS341 Fuel Pump DIY in UrS4/S6 - AudiForums.com

 

[<tuffty/>]

Have you checked the fuel pressure?

Intank conversions are not always reliable and personally I bother with that type of conversion... a decent S3 fuel pump(in working condition of course) is plenty for K04 levels of tune...

If your fuel pressure is low due to the pump being tired then replace it with a new OEM one... if you are running 350+ hp then get an inline pump to suppliment the intank one...

Also... when you first turn the ignition the pump has to prime to get pressure up... if you have less than half a tank this can take a while for the pressure to build and take longer to start

<tuffty/>

 

[Pedrosousa]

I haven't checked the pressure, it's 3bar all the time?

 

[<tuffty/>]

I haven't checked the pressure, it's 3bar all the time?

No... its a rising rate regulator so will increase with boost... should be around 3bar on idle/off bost then rise as boost does... at 1bar boost you should have 4bar fuel pressure...

<tuffty/>

 

[Pedrosousa]

I'll check pressure then... I also sent an e-mail to this guys:

Genesis Mk4 High-Flow Intank Pump [GINTANKPMP] - $249.00 : USRT, Usually Sideways Rally Team

 

[<tuffty/>]

I'll check pressure then... I also sent an e-mail to this guys:

Genesis Mk4 High-Flow Intank Pump [GINTANKPMP] - $249.00 : USRT, Usually Sideways Rally Team

Not sure how suitable that will be for an S3 as the pumps are different on the quattro

<tuffty/>

 

[Pedrosousa]

Not sure how suitable that will be for an S3 as the pumps are different on the quattro

<tuffty/>

I asked about that, because they are working with Doug from FrankenTurbo in the TT project!

 

[Pedrosousa]

In narrow band ecu's with vag com can I check something to see what's happening with fuel??

 

[Rosso TT]

In narrow band ecu's with vag com can I check something to see what's happening with fuel??

Check your fuel trims, if the multiplicative changes value mid 4th gear pull, like mine did, most probably the fuel pump is tired, also confirmed with a pressure gauge in the fuel system, pressure was going down on boost.

 

[Pedrosousa]

Today I saw that in my jobs car (A6 2.8 v6) the FPR it's a 4bar one, could this help to get a little more fuel just to check if it's pump problem... Or the pump wouldn't be able to raise the fuel pressure to 4bar???

 

[<tuffty/>]

nope... if the pumps not making the pressure now it will die on its **** with a 4bar and the fuelling will be miles out...

Find and fix the existing issue, don't bodge it together...

<tuffty/>

 

[Pedrosousa]

I'll check the fuel trims and the fuel pressure!!!

 

[<tuffty/>]

I'll check the fuel trims and the fuel pressure!!!

Good man

<tuffty/>

 

[Pedrosousa]

I couldn't test the car this weekend, because I'm working faraway from the car, but just to know more about the issue... If I have pump problems and I log the injector duty, it should be near 100%???

What's the blocks for fuel trims and injector duty?

 

[<tuffty/>]

http://www.ross-tech.com/vag-com/m_blocks/

<tuffty/>

 

[badger5]

if narrowband ecu, fuel trims will be relating to whenm lambda is active, which is idle and cruise throttle, not WOT

 

[Pedrosousa]

So the only way it's to read the pressure with a gauge???

 

[<tuffty/>]

So the only way it's to read the pressure with a gauge???

For fuel pressure yes...

<tuffty/>