M48 Lambda

[Andrew C]

I am running an M48 with a 4 wire Lambda. We ran on a dyno and used the dyno's meter to get our mixture around 12:1. consistantly.
The Lambda sensor is a new Bosch unit from Motec, and it is visable on the ECU screen. we have advanced tuning and logging enabled.

We took the car to the track, and after the session, downloaded the file. Lambda is reading 1.00 to 1.20 across the board, which is contrary tot he dyno results. We pulled the plugs, and it looks to be running on the rich side, so we are confused.

Is the a setup in the ECU software that might cause this? If the lambda is off, will it read at all? If we run it as wideband, can we adjust the engine temp that will control the lamda function?
As a note, the engine is a Porsche 911 race engine, air cooled. And the engine temp was only 60C ..
Thanks,
-A-

[FRASHD]

I think with the M48 you have to get Lambda enabled, It is free for 6 hours as is logging. Just last week I tuned a M4 Pro but the Lambda was inop. I will look at my old file from my car and check what the settings have to be on.

[MarkMc]

Hello Andrew,
You can check to see if your Lambda is enabled in the first screen of the software (the one with the grey, main menu options box). Along the bottom of the screen there is a grey line with all the options listed with a tick or a cross. If you do not have a tick next to the "Lambda" option it means your six hour free time has run out and you need to purchase the full Lambda upgrade.

If you have the option ticked and you have not purchased the full Lambda upgrade there should be a number next to it showing how much of your free time you have left.

Other things to check if you do have Lambda active is that you have set the Lambda channel correctly. In the Sensor Setup the Lambda channel parameter shold be "2" for wide band, this is the only setting you need in the ECU.

Next check is to make sure the sensor is wired properly, remembering that for reasons known only to Bosch the black wire is the Positive (+) and the grey wire is the negative (-). These should be wired to pins 31 (+) and 32 (-). The two white wires are the heater and just need ignition on 12v and chassis ground, it does not matter which way around each wire goes.

[Andrew C]

Thanks Mark,
We have Advanced Tuning, Lamda and Logging on our 48.

Sent the logged data to "Simon Wagner" here in the US, and he mentioned that our resolution was too low, and inorder to really see what is going on, we need to increase the resolution. How do I do that, is resolution the same a sampling rate? Should we make all sampling the MAX? we are not running telem, or a display at this time, just basic aircooled requirements.

We have lamda set to "2". running a four wire, and we double checked the pins, all good. THe heater works, verified with my hand ! (OUCH)...

We are getting ready to put a 2.9 stroke porsche on the dyno, and the base tune is yet to be defined. Lamda needs to be working, or just increase the resolution.

Thanks..

[MarkMc]

The resolution Simon is talking about should be the logging rate, this would generally always be on 20Hz for tuning.

[Andrew C]

Thanks Mark for all the info, logging is now set to 20Hz.. Ran on the Dyno, all looks good with AF mix per dyno meter, now, the LAMBDA is showing cold after I reconnect it, is there a pre-determined time delay before the heater is active? we have voltage and ground to the sensor, and signal wires ring out fine.. Sensor has 2 hours on it, and looks clean, no carbon buildup..
We ran for two hours with the LAMBDA unplugged and removed from the header. There was a fan blowing across the engine bay to aid in air flow for the Aircooled engine. Used the dyno to set A/F mix. After the two hours, went to plug the LAMBDA in to allow the ECU to do its thing, and it was reading COLD after idling for about 2-3 mins.. Check the wiring, looks good... Any ideas? Can I test the sensor before I buy a new one?

Thanks Again Mark..


Andrew

[Andrew C]

OK, Spoke to ANDY at Motec East here in the States, and it seems that the engine on the dyno, with all the cooling fans running, will not see the required temp for the sensor to change from cold to active, so we are going to swap the LM-11 for an Innovate LC-1 unit, and run a true wideband with a more powerful heater element for out=r application. Anyone have experience with this product? Anyone know what the programming perameters are for the M-48 to read the LC-1? 0-5V? and pinouts, the LC-1 seems to only use LA+ and the ground from the sensor goes direct to ground... Confirm? Thanks..

[RossB]

The LSM Sensor should work but it will need to see a rich mixture to start working. Once it sees a rich mixture and passes through stoich it should start to work, this may not happen when the engine is idling.

[Dragon]

LC-1 is OK but do make sure than the sensor does not get too hot. Otherwise, it will not work for long.
Use Logworks to check if lambda value is the same as displayed on MoTec software.
If not, use LM Programmer to adjust.

[Andrew C]

OK, I will fab a copper heatsink per the LC-1 Instructs to keep heat to a min on the sensor. The sesor is to be at 11 o'clock on the header collector, and in free air so heat should be ok.

Do you know the analog LA values for the sesor adjustment to be compatible with the M-48? I am planning on the sensor + lead to run to pin 31 and the sensor - to chasis ground, rather than pin 32, per the LC-1 instructs. I guess the LA - pin (32) on the ecu is open? or should it also see ground?

Thanks,