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Sensor grounds to Pin #18 or #20 and Can't set to Odd Fire

Posted: Wed May 19, 2010 7:30 am
by Richard0327
Hi All:
Over the past 2 months I have been trying to get the noise out of my MicroSquirt V2.00. I am using 2 VRs on the crank, wasted spark and want to set too odd fire but MegaTune wont let me. Can someone help me on that also. Any way I am running V2.89 and everything seems to run fine in simulation but as soon as I plug in the fuse for the coils everything goes nuts. RPM swings wildly 400 to 4000 RPM. I was thinking I had grounding problems with the Black board MicroSquirt and I was looking through some of the publication. I found 1 in "MicroSquirt General Information" by Bruce of 3 years ago "Grounding on MicroSquirt". I did everything it said to do with the grounding methods and then shielded everything but when I got to the section that said and I quote "Sensor ground - the coolant sensor, intake air temperature sensor, throttle position sensor, and external MAP sensor needs to be grounded back to pin 18 on the AMPSEAL" I noticed that the pin# did not match the pin# In the docs I have been using "MicroSquirt wiring" In the docs it said to hook all sensor grounds to Pin 20 not 18. In the docs pin 18 is labeled "N/C (ground)". I wouldn't even have taken a second look except that the board that was shown on the page is almost like mine. Can any one enlighten me on the proper pin#.
Any input would be much appreciated as I would really like to get this bike started so I can go on to step number next. Thanks to all.

Re: Sensor grounds to Pin #18 or #20 and Can't set to Odd Fi

Posted: Mon Jul 26, 2010 9:14 am
by Matt Cramer
Richard0327 wrote:Hi All:
Over the past 2 months I have been trying to get the noise out of my MicroSquirt V2.00. I am using 2 VRs on the crank, wasted spark and want to set too odd fire but MegaTune wont let me. Can someone help me on that also. Any way I am running V2.89 and everything seems to run fine in simulation but as soon as I plug in the fuse for the coils everything goes nuts. RPM swings wildly 400 to 4000 RPM. I was thinking I had grounding problems with the Black board MicroSquirt and I was looking through some of the publication. I found 1 in "MicroSquirt General Information" by Bruce of 3 years ago "Grounding on MicroSquirt". I did everything it said to do with the grounding methods and then shielded everything but when I got to the section that said and I quote "Sensor ground - the coolant sensor, intake air temperature sensor, throttle position sensor, and external MAP sensor needs to be grounded back to pin 18 on the AMPSEAL" I noticed that the pin# did not match the pin# In the docs I have been using "MicroSquirt wiring" In the docs it said to hook all sensor grounds to Pin 20 not 18. In the docs pin 18 is labeled "N/C (ground)". I wouldn't even have taken a second look except that the board that was shown on the page is almost like mine. Can any one enlighten me on the proper pin#.
Any input would be much appreciated as I would really like to get this bike started so I can go on to step number next. Thanks to all.
Both Pin 20 and Pin 18 are grounds, but not all MicroSquirt harnesses have pin 18 connected. Either one can work.

On the issue with setting odd fire mode, please post a copy of your MSQ; I need to check your settings.