URS6 Way Too weak!!!

[HMS-S6]

My S6 is still running like a bag of S**t after the head job and all other attempts to make it work!!!!!

I recently got VAG-COM and according to that it's running way too lean on full throttle, the car has been boost checked from the induction hone to the throttle body and all is spot on. All Breather hoses are good and breather valves are new! Also am on my second ECU and 3rd MAF, and the fuel pump is new with 14V to it (new filter too)

Anyone come up with theories on why its running painfully lean or how i can trick it to run richer to prove my point??????

Also, does anyone have any maf figures from a working car on full throttle???

[driftin jo]

-fpr ?

[prj]

My S6 is still running like a bag of S**t after the head job and all other attempts to make it work!!!!!

I recently got VAG-COM and according to that it's running way too lean on full throttle, the car has been boost checked from the induction hone to the throttle body and all is spot on. All Breather hoses are good and breather valves are new! Also am on my second ECU and 3rd MAF, and the fuel pump is new with 14V to it (new filter too)

Anyone come up with theories on why its running painfully lean or how i can trick it to run richer to prove my point??????

Also, does anyone have any maf figures from a working car on full throttle???

Huh, how would you see that the car is running lean on full throttle with VAG-COM?
Not really possible I am afraid.

Could you tell me how you came to this conclusion, or show me your initial log/data?

[HMS-S6]

Just from the Lambda reading, as its all i have. I can e-mail you the data if you like?

From my experience the car even feels and sounds weak!

[HMS-S6]

-fpr ?

Tried, thanks

[prj]

Just from the Lambda reading, as its all i have. I can e-mail you the data if you like?

From my experience the car even feels and sounds weak!

The stock lambda sensor does not show anything of interest in VAG-COM when you are at WOT.
In fact it's not even evaluated when you floor the thing, so you see whatever there was as the last value when it was evaluated.

Or do you have a separate WBO2 gauge fitted?

[HMS-S6]

The stock lambda sensor does not show anything of interest in VAG-COM when you are at WOT.
In fact it's not even evaluated when you floor the thing, so you see whatever there was as the last value when it was evaluated.

Or do you have a separate WBO2 gauge fitted?

No, i wish i had. Where are you based?

[prj]

Estonia?
Yeah, I can't come to take a look at it, if that's what you are asking

You mentioned that the car has been leak tested from the induction hose to the throttle body.
So that means you blocked the throttle body?

That's a bad idea because that will never show a leak in all the vacuum hoses that are connected to the inlet manifold.
Try doing a pressure test with the intake connected.
If you think the pressure is going to the exhaust, move the car in top gear a bit, although with stock cams it's highly unlikely.

Also make sure the check valve from the breather doesn't leak. It's near the T piece for the EVAP.

[HMS-S6]

Estonia?
Yeah, I can't come to take a look at it, if that's what you are asking

You mentioned that the car has been leak tested from the induction hose to the throttle body.
So that means you blocked the throttle body?

That's a bad idea because that will never show a leak in all the vacuum hoses that are connected to the inlet manifold.
Try doing a pressure test with the intake connected.
If you think the pressure is going to the exhaust, move the car in top gear a bit, although with stock cams it's highly unlikely.

Also make sure the check valve from the breather doesn't leak. It's near the T piece for the EVAP.

Do you come to the uk often?

Yeh it was the bung kit which ends the test at the throttle body.

With manifold connected as in with cams out so all intake valves are closed?

The check valve is a new Audi part.

[prj]

No, no need to take cams out or anything.
The important thing is that the exhaust OR the intake valves are closed.

At 0.8 bar or so, with which you should leak test, there will be almost nothing going past the valves or the piston rings.
If that was different your engine would be dead.

[rs200]

WBO2 is only relevant if we talk about lean or rich mixture.
how much of boost do you have?
maybe you don't have boost leak , but you don't have enough boost. than car fells weak on high revs!

[macspring]

I know your urS6 is currently evading your efforts to get it to run correctly, stick with it as it must be something.

I have one with about 150k and it and while it gets it’s oil changed and filters etc, it gets plenty of pressure from me and got even more from the previous owner and it never misses a beat. It impresses anyone who drives it.

So hopefully you get to the bottom of problem afflicting yours. Test all of possibilities thoroughly, incluidng testing of the various parts of the loom. Hopefully with the hep of other members on here you nail.

The, usS6, really are exquisite when they are running correctly, but a pain to sort out if you’re not an expert, or don't have a mate nearby who is.

Best of luck, and kind regards.

p.s. Post up the cause, in due course.

[HMS-S6]

WBO2 is only relevant if we talk about lean or rich mixture.
how much of boost do you have?
maybe you don't have boost leak , but you don't have enough boost. than car fells weak on high revs!

WB02 is what i need, i agree but i don't have one or know of anyone in my area willing to lend me one unfortunately

The car's boost levels are 0.8 on my standard ECU and 1.2/1.3 on my 290 one and thats according to the mechanical gague and the dash.

[HMS-S6]

I know your urS6 is currently evading your efforts to get it to run correctly, stick with it as it must be something.

I have one with about 150k and it and while it gets it’s oil changed and filters etc, it gets plenty of pressure from me and got even more from the previous owner and it never misses a beat. It impresses anyone who drives it.

So hopefully you get to the bottom of problem afflicting yours. Test all of possibilities thoroughly, incluidng testing of the various parts of the loom. Hopefully with the hep of other members on here you nail.

The, usS6, really are exquisite when they are running correctly, but a pain to sort out if you’re not an expert, or don't have a mate nearby who is.

Best of luck, and kind regards.

p.s. Post up the cause, in due course.

Thank-you. Mine's on 163k and had never been right, it started as intermittent but is slowly getting worse. Feels JUST LIKE a MAF fault.

[prj]

Swap a known working set of coils on it