How to use auto tune???????

[genderen]

Hi,

I'm a newby with megasquirt and tunerstudio. I have a Audi 5000 turbo which is converted to LPG. This is controlled by a MS2.

I have got the system working now and I'm ready to set the system. I would like to use the autotune function from the VE analyzer live and let this update the controller to get the car running OK.

How should I start with this, the system is equipped with a wideband lambda sensor (tech edge 2j2/9).
The analyzer will work from AFR table 1 in this case, is it sufficient to set all values to the right afr settings into AFR table 1?
If yes what will be the right AFR value for lpg (I have found 15.7)?

When this is sorted, I suppose that the analyzer will take care of the VE table by updating it to the requested AFR readings is reached?

I would also like to control the orginal PWM idle valve, can someone help me regarding these settings! It's a 2 wire pwm valve. In TS i have 2 pwm options, pwm warm up and pwm closed loop. What's the difference? I think I need the closed loop setting? I furter on have no idea how to set the idle control and PWM settings, if someone can advise me that would be helpfull.

I'm also going to use "direct coil" to control the orginal coil with original distributor. I have fitted a 60-2 triggerwheel and I'm going to use the orginal hall sensor in the distributor (this has one window). What's the best way to set this extra hall sensor? Via triggerwheel settings, dual wheel with missing tooth? That's enough? Perhaps first see if the engine will run on a fixed timing setting, before working from a table? Also any ideas to get a nice table for this?

As you can see, lot's of questions. again i'm new with this stuff. I hope you don't mind.

Thanks in advance for any help with this!

Thanks

Kind regards,

Patrick (from the Netherlands).

[trakkies]

You don't need the sensor in the dizzy if you've fitted a trigger wheel. The dizzy will simply send the spark to the correct plug. But it would be better to go to wasted spark and eliminate the dizzy totally.

[LT401Vette]

The analyzer will work from AFR table 1 in this case, is it sufficient to set all values to the right afr settings into AFR table 1?
If yes what will be the right AFR value for lpg (I have found 15.7)?

If you used the standard AFR calibration selections under the Tools menu, then you would want to still use 14.7:1 as stoich with the LPG on the AFR . It might be easier to start working in Lambda where you just know that 1.0 = stoich

[genderen]

You don't need the sensor in the dizzy if you've fitted a trigger wheel. The dizzy will simply send the spark to the correct plug. But it would be better to go to wasted spark and eliminate the dizzy totally.

Hi,

Sorry to mention this, my audi is a 5 cylinder, it's a little different then a 4 cylinder on which wasted spark can be used. This kind of a challenge, I would need the cam sensor as a reference I would say.

If you used the standard AFR calibration selections under the Tools menu, then you would want to still use 14.7:1 as stoich with the LPG on the AFR . It might be easier to start working in Lambda where you just know that 1.0 = stoich

I'm sorry not sure what you mean, there is a wideband lamda sensor fitted on the engine. From which I can see the afr values in tunerstudio. I thought that autotune uses this values to adjust the VE table to get the desired afr? Must say I'm not sure if the calibration values are correct.
This are the specs from the lambda:

Tech Edge 2J2/9 WBo2 Features
Reads from λ = 0.61 (AFR = 9.0) to free-air.
Within +/- 0.1 from AFR 11 to 17 (unleaded).
Differential WBlin wideband 0-5 Volt output.
Bosch LSU 4.0*/4.2 (2J2) or LSU 4.9 (2J9) compatible.
WBlin configurable (9.5 bit DAC) from AFR=9.0 to free-air.
Auto-cal button calibration with sensor in free-air.
NBsim narrowband (7.5 bit, re-programmable) output.
2 analogue 0 to 5 Volt inputs sampled at up to 40/sec.
RPM input from Tacho or ECU for logging.
PULSE input from VSS sensor or cruise control for logging.
10.5 to 19.5 Volt DC operation (up to 3 Amps).
Free logging software (optional upgrade available).
Fibreglass covered cable - ABS plastic case - repairable!
has RS232 output for no loss of wideband accuracy.
link http://wbo2.com/2j/default.htm

When I select custom lineair WB in can fill in the data as I can find on the link above: 1 volt = 11AFR and 4 volt = 1AFR.
Is this the way to do it probarly?


Thanks,

Regards,

Patrick

[trakkies]

If you're retaining the dizzy, you don't need its internal trigger if you're using a trigger wheel. The trigger wheel determines the timing and the dizzy makes sure it gets to the correct cylinder. If you went to COP, you would then need a cam position sensor, since you can't use wasted spark.

[LT401Vette]

I'm sorry not sure what you mean, there is a wideband lamda sensor fitted on the engine. From which I can see the afr values in tunerstudio. I thought that autotune uses this values to adjust the VE table to get the desired afr? Must say I'm not sure if the calibration values are correct.
This are the specs from the lambda:

Yes, but here is the problem...
Lambda represents the stoich ratio, so 1.0 is perfect stoich with any fuel. However the look up tables the firmware uses are gasoline AFR if you use the pick list. The firmware uses that table to determine what AFR any given voltage represents. But that AFR would be in 14.7:1 based gasoline AFR. That means 14.7:1 really represents 1.0 Lambda. So if you are using an AFR view, you should still think in 14.7:1 gasoline AFR's as that is really 1.0 lambda.

Alternatively, if you have a linear WB controller, you could use custom linear in the calibration tool. That would allow you to set the right AFR's for your fuel, then the targets would make sense in AFR. I'm not sure if this would have any odd side effect in the firmware though.

Ideally the firmware would do everything in Lambda, then TS could convert that to the proper AFR for the selected Fuel, but it is already done the way it is now.

But to your question somewhere above, TS does always target the AFR you have on the selected AFT target table. It is basing that off the afr reported by the afr outputchannel though, so if it is reporting 1.0 lambda as 14.7:1, you would want to target 1.0 Lambda as 14.7:1

[genderen]

Hi Phil,

I have used now AFR targer 14.7 with auto tune, which I got working OK now. Thanks for your help. The following issue is occuring, underneath the 3000 rpm the car is sputtering and not driving smoothly above thath it works OK an LPG. I can only think of the fact that the stock ignition is too retarded under this rpm range. When driving on LPG it should just be a little adavanced. When running the car on regular petrol instead of LPG, it drives OK.

I was also planning to let the MS control the ignition (direct coil).
I have fitted a 60-2 triggerwheel to the crankshaft pulley. I wouls also like to use the hall sensor in the distributor as a cam reference.
Somehow I cannot get it to work OK. I cannot get a signal from the cam hall sensor.

With diagnostics I can only see a crank signal.

Please advise how to set up Tunerstudio correctly for the set up I have! So I can get the ignition working!

Please advise,

Thanks,

Patrick