The stock 02 sensor is not the most accurate way to measure a/f ratios, but you should try to shoot for 0.9 at WOT.

Also the ignition timing should not pull back the timing more than -10. (at the very most)

Is your programming at the maximum duty cycle for the injectors?

DK

 

to get Injector Duty cyle to see if the injectors are maxed.

Have you checked the fuel pump flow? It's spec'd in the Bentley manual (which I don't have on me -I think it's around 108 lph free flow @ 14V). Have you changed the filter?

 

, actually, m has to be converted to n. It won't be accurate though as I don't know the T per unit time the MAF was taken and also the volumentric efficiency is non linear, but it will at least give an idea of what the KO4 is doing per RPM. I'll do some excel during lunch

Mike, good data. Don't know what the fuel inj time units are, but at first glance, they do not track with rpm and they seem to be maxed out at the same time your O2 sensor indicates leaning out. It appears that the Wett software is not allowing the injectors to open any longer. I'll plot some duty cycle stuff for my own curiousity, but it does look like you are leaning out above 2500 rpm, increasing EGT's most likely, and NOX is a by product of high temperatures too. I wouldn't change those injectors just yet.

 

According to Tim Marren anything above 14ms is considered "static". This means, for all intents and purposes, the injector is wide open. I have 16.32ms which is as much fuel as is available. 20+ms does nothing more.

Mike O.

 

Try Ziff Davis - ZDNET

 

...according to Tim Marren. He is a Bosch expert. Anything above 14ms is "static" and will not produce any additional flow.

I know I need more fuel and the only way looks like 27 or 32 pound injectors.

Mike O.

 

Changed it at 100,000 miles

 

RPM.....Engine..Inj.....MAF....Throttle..Ignition. ..O2S....Duty....Boost (psi)
...........Load....Time........................... ..................Cycle

1700....5.30....10.94....27.36....85.1....-13.50....0.555....31%....-0.4
1875....6.30....10.56....37.43....84.6.....-6.80....0.680....33%.....3.0
2180....8.20....15.10....55.69....84.6.....-4.50....0.765....55%.....8.0
2580....9.75....16.32....78.12....84.6.....-6.00....0.815....70%....12.2
3300...10.05....16.32...111.94....84.6....-10.50....0.815....90%....15.4
4040...10.00....16.32...129.51....84.6....-17.30....0.820...110%....13.8
4540...10.00....16.32...122.50....84.6....-17.30....0.835...123%.....9.3
5060...10.00....16.32...161.87....84.6....-17.30....0.855...138%....13.7
5560...10.15....16.32...180.97....84.6....-16.50....0.855...151%....14.2
6060....9.80....16.32...187.08....84.6....-16.60....0.835...165%....12.7
6420....9.20....16.32...187.11....84.6....-14.30....0.805...175%....11.2


Pardon for the dots, but I didn't want to import a picture Anyway, I assumed your injector "on" time was in milliseconds, so that was a quick conversion to duty cycle. Basically, ignore any meaning to a number over 100%. It just means your injectors are fully open at that rpm.

For the boost, I use the MAF mass as gm/sec, calculated what a density would be should your intake temps are around 40C (I have no idea) and fudge a few numbers with some gas laws and came up with the boost data. Note that the MAF reading at 4540 rpm is a fluke.

Anyway, it does look like what you thought all along. despite 100% duty cycle, you are running lean at WOT - although you can fix your WOT later to get larger throttle opening Looks like larger injectors are in the order. But that could screw up your idle and cruising too

Now one thing that bugs me is that you are not producing a lot more boost compared to a K03, so why the 100% duty cycle still gives a lean readout, hmmm. Something still not right

 

I agree. I played with your data and reply above.

 

I'm not sure which Group/Field Mike was looking at, but I don't think those numbers are how much the igintion was "pulled back", I think they are actual ignition timing. VAG-COM shows actual ignition timing which is BTDC as negative and ATDC as positive.

Nontheless, the timing in the 1800-3000 range looks like it's being pulled back quite a ways. It would be interesting to compare actual vs. mapped. I can do that on my VR6, (group 10, fields 3 and 4) but I'm not sure the 1.8T has that data.

BTW, *native* data logging will be available soon. Should give more data points..