MicroSquirt.com read only forum (Jan.15,2018)

Hi all....
Finally got my engine up an running. Current set up is MS2 with halleffect pick up triggering from crankshaft. Current software is 2.34. Ms2 is feeding the engine throug 4 bosch 0 280 150 791 about 400cc injectors (high impendance.) I`m using the stock bosch 124 ignition module. The engine fired up right away after I figured out the cranking tach error.

One question. Is it normal that the engine must crank over several times before the tach signal appers?? It almost seems like it aint going to start... Maybe this will change if i set the cranking trigger as trigger return and not calculated?.... But the initial trigger value is 91degree BTC and trigger retur will probably way to early for cranking... Does anybody have an opinion on this?

Finally got my engine up an running.

quickerz,

Congratulations!

Is it normal that the engine must crank over several times before the tach signal appers??

No, that's not usually the case, though you have to make sure it's the signal and not MegaTune slow in reporting it (if it's having resets or comm issues for example). Do a datalog for us to have a look at.

An initial trigger value of 91° BTDC is way too early for cranking, so don't use that. You would have to move the trigger to the 0° to 10° BTDC range before trigger rise is a viable option.

Lance.

Ok. I`ll try to run a datalog this weekend...
I`ve set the "skip pulses" option to 10. I dont know why I did this, but i recon that MS skips the ten first pulses befores it calculates rpm, and outputs a spark... I`ll try to reduce this later today..

I`m also going to try tuning with Innovatives broadband o2 sensor with Autotune. Anybody tried this??
When tuning this way MS2 changes the values in the VE tables so that MY AFR values are met..... Is this correct?

Jon

MSII. V3 2.33 Edis

I set the LM1 for 0-5v 10-20 AFR and used autotune only to find that the LM1 reported the AFR about 0.5 richer than it really is around 14-15:1 compared to a calibrated analyser (MOT equipment)
This meant autotune set all the VE values too lean.
The LM1 calibrated OK in free air and I set output 1 to feed the MS O2 input.
The LM1 reading and the megatune gave very similar values so if I can`t get it to read more accurately I will "adjust" the LM1 output programming to reflect reality more accurately.

Autotune is magic.

I didn`t find the time this weekend to run a datalog, but I did however change the "skip cycles" donwn to three. (lowest possible number) Now it fires up right away.. I`ve also tried out the autotune function and it works... But when the lm1 reports AFR=13 megasquirt puts out aprox 14, and thats its when the output 2 set to 0V@AFR10 and 5V@AFR20. The output of lm1 is Stochiometric is 2.50volts.

Bubble: Have you replaced the voltage values to any "bogus" value so that the ms2 unit reads the correct AFR?

When the wideband sensor is connected in the tailpipe there must be a certain delay before the exhaust gasses from the combustion reaches the sensor. In MS I think this is called transport delay. Witch value would be "correct" here?

For your wideband 02 readings to be accurate in Megatune-- do you have the wideband sharing a it's grounds with the ECU? If not there will be a voltage differential between the ECU and wideband and that will cause the error in the readings in MegaTune or on anything using the analog outputs that's not grounded at the same place as the wideband.

Other than that if you've got the wideband configured for 0-5v corresponding to 10:20 AFR, and this is also the settings chosen in the MegaTune configurator then you should be golden. (If MS-II then you also need to calibrate the AFR table for the Innovate 0-5 10:20)

We had a few cars on the dyno last weekend (MS Meet) with Innovate widebands, for one of them we put the dyno shop's wideband in the exhaust and compared the readings to the Innovate-- they were dead on even with each other.

quickerz
I think you should find stoich at 2.35v not 2.5v

Jerry
the sensor engine and ms grounds all meet on the firewall.
I think the calibration button may have been depressed as I have only chucked the LM1 controller in the glovebox whilst using the laptop on the passenger seat. My shifts this week do not let me get any decent time in the workshop but I`ll remove the sensor and recalibrate it ASAP and then see if its any better. The redings are consistant so I`m sure its something I`ve cocked up not a hardware fault.

Nig