S2 with AAN ignition mixture rich, cannot find possible cause

[rs200]

I hope that benky do that conversation like it have to be. tomorow will I take a look and write exactly how it is.

[prj]

in that car is stock AAN ECU 100% and it was never been opened... NEWER..

so why my car with aan ecu , benkys car with aan ecu and friends car on 200 20v with 3b ecu , we all have 0.2 bar on dash ... we all..? why?

what will you say? that all 3 cars are not good?

Did you rewrite your dash computer? I am 100% sure you did not.
Read what I wrote, I told you exactly why the dash computer shows a lower value. And it is purely logical that it shows an _even lower_ value when you use a 250kpa sensor.

The pressure is pretty much the same on 3B as on AAN, use a vac gauge. The 3B instrument cluster just shows it wrong.

[benky]

Finnaly i figured out the thing about pressure on 3b and aan. Today i will look for leak in vac/fuel line. Is it useful to remove battery for some time, and try again?

[prj]

You can, if you want to clear the ECU.
Might be a good idea to do to reset fuel trims.

P.S.
What about the software in it?
If you have software for bigger injectors, then you will run lean...
Try stock AAN chips or software made for stock AAN.

I can send you the stock files if you need...

[qba]

Few days ago pulled new wire from O2 to ECU. No remarkable changes. Now trying to change soft. Tomorrow testing my old soft with another S4 AAN. Lets see how it acts.

[benky]

i removed battery and nothing happened and I can't start engine with 3bar when i put 4bar car normally start and runs. Inside is stock S4 ECU. No fuel leak,

[prj]

i removed battery and nothing happened and I can't start engine with 3bar when i put 4bar car normally start and runs. Inside is stock S4 ECU. No fuel leak,

Well, then something is still wrong somewhere.
Maybe something is wrong with the 3 bar FPR that you have.

Basically when converting from 3B to AAN you only need to change the ECU+wiring+add coils.
You don't need to change injectors or FPR, because the amount of fuel that the 3B injectors flow at 3 bar is identical to what AAN injectors flow at 4 bar.

So, think when you converted your car, what you changed. If you also changed injectors to AAN injectors, then you will need 4 bar FPR.

[qba]

Well, after a year I hope I found the bad part that was causing all the mess. I found out that solenoid between inlet and carbon canister was stuck open and engine was pulling petrol fumes in, and that overfueled the mixture. The bad thing about it is, that NB lmbda still doesn't want ot work properly and CO coming out of the tailpipe is bouncing up and down between 0,4 and 0,8.(which is remarkably better than 3,0 and 2,0 I had before) Allready thinking of buying Innovative WBO2 and setting the analog line out to replace original lambda. Can anyone tell me what ise frequency that ECU uses to read NB lambda and can Innovative analog line replace original?

[UrS4boy]

N80 Evaporative Emissions and G39 O2 Lambda info

Well, after a year I hope I found the bad part that was causing all the mess. I found out that solenoid between inlet and carbon canister was stuck open and engine was pulling petrol fumes in, and that overfueled the mixture. ...

I am happy that you think you have solved your problem but I am very skeptical that all of the problem was due to the N80 Evaporative Emissions Control Valve (solenoid). Since you are still having G39 O2 (Lambda) sensor problems, I would suspect that real problem is the G39 and the N80 just made the G39 problem worse.

Here is some N80 info:

http://forums.quattroworld.com/s4s6/msgs/21014.phtml

Here is some G39 info:

http://forums.quattroworld.com/s4s6/msgs/21012.phtml

[qba]

will have to measure lambda next week with ocillograph, maybe it's just faulty indeed.

[qba]

well the graph shows that there is no movement in idle!:-S. BUT funny thing is that sensor reacts really fast when i touch the gas pedal or release it. I m not very surtain that its the lambda only because i have tryed others (not new) and they react the same Its quite a headache. Could it be some other sensors or maybe some relay?

[prj]

Bring the car here and I will find what is wrong with it.