AFR for MC2

[SamFM]

Hi everyone!
Sorry for English again. I think it will be better than machine translating still.

Sorry for all of you, who I was talking to regarding Buergi chip, but I have managed to install already purchased chip from KL-Racing (sweden).
It's also for 0,9 bar and works fine. The hardest part was to integrate in into the MAC-14 ECU without damaging the ECU. It worked for me only at 3rd attempt.

So, I did a test drive, and my wide-band lambda shows very rich mixture: AFR on full-throttle is less than 10:1
While, at idle it's stable at 14.7:1

Could you please look at the video and tell is this AFR OK and which AFR should I target?
Also, will it be Ok, if I will make my engine leaner by messing with CO adjustment at the fuel distributor or I better reduce the fuel injector flow by tuning the channels of fuel distributor?

https://www.youtube.com/watch?v=LhMVPoMLFSc

[Poldy]

hi,

google after AFR oder Lambda Table. This will explain it to you. I would say it is to rich or you have not enough boost. Air or or Water temperature could also be worng or the fuel Table of the chip is just crap.

1.4 bar is posible with KE and the Last Burgi Version, dont know what your chip can ?!

Poldy

[SamFM]

Pardon for long reply. Had to move outside my county.

So, I was telling the overboost pressure. Not absolute. And, correction, the pressure with KL-Racing chip is 1 Bar (meaning 2.0 Bar absolute).

PS. Main reason why I asked was to cure the engine unwillingness to rev over 4800 rpm (feels like something prevents engine from doing it). And on the AFR gauge I see that on revs from 2000 to 4000 the AFR is around 11-12 at full throttle. But after 4000 it starts to lean out to about 13.

I changed almost every component: rebuilt fuel flow divider with new membrane and aligned the flow between all 5 injectors (at the level of 180 cc \ min), rebuilt Warm-Up regulator so it stays at specified pressure. But problem stayed.

What I did next:

Fuel:
- Replaced bosch 040 pump with Pierburg and changed fuel lines + fuel filter
- Set CO levels by using special multimiter to 50% at idle
- Changed lambda sensor
- Installed all new fuel injectors
- Installed extra fuel pump relay to increase the voltage on the pump
- New fuel relay
- Filled car with 100 octane fuel

Ignition:
- New spark plugs (EQUIYEM) rotor, cap and wires (Beru)
- New ignition coil (new type instead of old round one)

But nothing changed. I've even installed another fuel distributor that I set up for 200 cc \ min fuel flow, but nothing changed again.
Car still can't rev past 4800-5000 rpm and lean out to 13 AFR.

I'm beginning to think that I may have several of problems below:

- Too much backpressure on the exhaust side (though, I have cat deleted + straight flow rear resonator)
- Something with alternator \ voltage to the fuel pump that drops at high boost and rpm.
- Maybe, new detonation sensors (round type) are tightened incorrectly (should be 15 Nm, right?)
- Finally, maybe my engine is just too worn out and at high RPM too much oil fumes and gasses comes through piston rings (my oil consumption is about 500 ml per 1000 km)

Any advices?

[Poldy]

I think you going the wrong way.
1. Take a drive an then read out the log file from the ECU maybe you see something. (Diagnose over LED)
2. The stock pressure from MC is 1.6 bar absolute / 0.6 relative
3. 1.4 bar is emergency
4. Bürgi ship hast 1.9 bar absolute / 0.9 bar relative, Some Versions go up to 2.4absolut/1.4 Relativ

Check the full load switch on intake.
Disconnect the “Multifuzzi” und take a test drive. The hot warning Contacet maybe block more boost.

All vacuum lines and Boost lines should be 100% tight.
The Check all Sensors

[Bastian]

Don't forget to check your crankcase ventilation system (PCV valve and all those hoses). If you're getting too much oily blow-by into your intake the knock sensors step in and the ECU reduces boost/fuel as well. You can also install a catch tank to stop oil from the PCV system to enter your intake.
0.5l/1000 km isn't too much, though, especially when driven hard. I don't think that's the reason why the ECU doesn't allow full boost.

I`d say this is likely to be a sensor. Multi-function temperature sensor, IAT sensor, WOT switch are the most likely candidates.

Have a look at the trusty old SJM checklist: http://www.sjmautotechnik.com/trouble_s ... boost.html

If all that doesn't get you anywhere, swap the stock chip back into the ECU.

[SamFM]

I think you going the wrong way.
1. Take a drive an then read out the log file from the ECU maybe you see something. (Diagnose over LED)
2. The stock pressure from MC is 1.6 bar absolute / 0.6 relative
3. 1.4 bar is emergency
4. Bürgi ship hast 1.9 bar absolute / 0.9 bar relative, Some Versions go up to 2.4absolut/1.4 Relativ

Check the full load switch on intake.
Disconnect the “Multifuzzi” und take a test drive. The hot warning Contacet maybe block more boost.

All vacuum lines and Boost lines should be 100% tight.
The Check all Sensors

Did it as well: I got VAGCOM reading my MAC-14 and no single fault code.
My full-throttle switch is working (N75 does that "click" sound)
And Multifuzzi I replaced several times till I got BEHR one. Tried ride with unplugged Multifuzzi, but results are the same.
So, the car don't work in "emergency" mode.

Vacuum lines maybe..
Anyways, thanks for the advice!

[SamFM]

Don't forget to check your crankcase ventilation system (PCV valve and all those hoses). If you're getting too much oily blow-by into your intake the knock sensors step in and the ECU reduces boost/fuel as well. You can also install a catch tank to stop oil from the PCV system to enter your intake.
0.5l/1000 km isn't too much, though, especially when driven hard. I don't think that's the reason why the ECU doesn't allow full boost.

I`d say this is likely to be a sensor. Multi-function temperature sensor, IAT sensor, WOT switch are the most likely candidates.

Have a look at the trusty old SJM checklist: http://www.sjmautotechnik.com/trouble_s ... boost.html

If all that doesn't get you anywhere, swap the stock chip back into the ECU.

Yep, thanks Bastian. I've bought and installed new PCV hose from 034 motorsports. Nice idea to pull out the PCV hose from the intake boot. Maybe I really have a lot of blow-by.