Former Megaquirter, now assisting friend in Genboard V3.3 with 1.0.73. See \MembersPage\MTRacing.
Needed to consolidate info regarding config.txt, and find out what MegaTune is doing to it, created
http://scirocco.dyn.dhs.org/cheapassron/MT/VEMS%20config%20helperV2.xls
Or see Config Helper on docs page.
12 May 09
After several month's of part time work, the Camaro has started. Here are a few of the problem areas we encountered. These fall under the general heading "check the dumb stuff first."
- No trigger. It doesn't matter what VR sender we had, we were getting a decent signal on the oscilloscope but no triggering at the VEMS. Using a .wav through a PC speaker output *would* give us a trigger, but full of trigger errors. Learned that the VR generated signal was riding on a DC bias, preventing 0V crossovers that are required for triggering. Tried a 'cheater' wire from the VR to the VEMS, bypassing the webstore-supplied harness. Presto, trigger. Why? the black wire in the harness which we were relying on to carry the -VR signal was not connected - it was trimmed off inside the harness, under shrink wrap. The signal was coming in great but with no ground reference, it's not carrying much influence back at the VEMS. Got that fixed and all was well. It did meter out OK, but we think it had incidental contact with the shield. So, after a month of messing around, looking at the Genboard, the LM1815, the supporting components, etc., we learned that we were relying on a wire (in the premade harness) to be connected, that wasn't.
- Couldn't get all the injector LED's to fire (using a test connector with 8 LEDs soldered in). Just after the above, with no other changes, four of the eight injector LEDs mysteriously wouldn't light up. We played with config items for three weeks, getting very frustrated. Finally we decided to make sure the LEDs were not bad, so we swapped the ignition LED test connector with that for the injectors. Presto, all worked! We didn't know whether to celebrate or kick each other. Some sort of contact problem in the connector caught us out. Why would we have suspected that? Hell, they had been fine - I recall them lighting when we triggered with the PC speaker...or do I???
Again, CHECK THE DUMB STUFF FIRST.
20 June 09
Very Frustrated
To anyone who can help, please do!
We are very early in tuning stage.
With the engine in what I believe is the afterstart condition, warm engine, pulsewidths are 24+msec, it's stinky rich.
I know our VE table needs tuning but this condition doesn't seem right. Where are we wrong?
config.txt, tables.txt, msq, and datalog are at:
http://www.scirocco.dhs.org/cheapassron/MT/jun202009/
1.0.73 firmware, Chevrolet 417in3 V8, firing order 18436571
Please help,
Ron