Megasquirt woes... (fixed!! it runs!!)
 

I can't imagine what went wrong...

I tried to boot up my megasquirt (previously was working before modding for miata). I had the megastim plugged in on one end.

I can't get it to communicate so I follow the detail communications troubleshooting.. loopback test the cable, loopback test at the cpu.

Then I run the downloader again. While I do that C16 went up in a puff of smoke.

Any idea what I screwed up?

1997 miata

Check that your power supply is ok and is not outputting a higher voltage than that needed (up to 15V should be okay). Also check that the polarity of C16 was ok (did you install it the right way?)

Dimitris

I double checked power which was fine. I replaced C16 (the polarity was correct). It seems to be working fine now. I read an MSextra post from DIYautotune that said C16's have burned out for no reason before...

Ok.. so now I've got the firmware loaded, the diypnp basemap loaded.

It just sits and pins betweeen zero RPM and max RPM. The stim doesn't seem to have any control. Does anyone know what that might mean?

Sounds like you may have a config error.

http://www.msextra.com/forums/viewto...?f=101&t=31532

Hmm... I found that I didn't have the second bank of injectors turned on which helped the bouncing RPM. Now it just shows zero.

Can a megastim 2.1 provide the proper signalling to the CAS input to allow this to even work?

Does anyone have any further advice on base tuning files? I have used the diypnp base configuration file.

http://www.diyautotune.com/diypnp/ap...7-18bp-mt.html

Sorry, but you need a JimStim to properly simulate a 4G63 signal.

Whew... I guess I may not really have any problem then..

Should I plug in in and try to start the car? or wait for a jimstim?

Whew.. I was a bit nervous there.. but I plugged it in and started tuning.. Works like a champion!

I'm having this same problem, but I am also failing my port test on tuner studio. I've been troubleshooting for the past few hours, and everything seems fine. But I can't imagine that it is normal to fail the port test.

Did all the serial tests and power tests, and reinstalled studio, and reloaded msq, and rebooted ms2 with newest msextra code. When I go into the gauge window on studio I get all readings except for tach, which I'm not able to get cause of megastim. Should I just wire it up to the car and crank?

Ok so I think I'm in the clear. While my port check wasn't working, I could still go to the gauges and everything was working except for rpm, which is expected since, as stated before, Megastim v2.1 is not able to generate the signal required for 4g63 inputs (also my CLT and O2 were a little crazy but unimportant now). If you are having this problem with the port check then try this updated port check before doing anything else.

http://www.msextra.com/doc/general/files/portcheck.exe

Worked for me, so I should be able to begin wiring tomorrow!