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

Alright, so got the car idling and everything the other day.

Tried to drive it down the road the other day, and the MS cuts out. Try to start the car, none of the lights would flash. So I cut power to the MS, and turned it back on, start the car get it idling. Does the same thing after a few secs, requires me to turn power to the box on and off.

So, I tried to drive it again today, stayed in the driveway till WUE went off, went to pull out, started going down the road. I could barely touch the gas, or it acted like it wanted to stall out. So most of my driving was idling. Then all of a sudden, it starts idling bad, the gauges went crazy in megatune, then the gauges went blank, then car died. Reset the box again, started, 10 secs later, all over again.

Finaly tow it back home, in the driveway, started car, gauges went nuts, even though megatune said WUE was off, the light came on, on the box then it stalled out again.


I have an 89 Iroc 350 SBC TPI, with an HEI mod
32lb injectors, 255 pump
I attached my log, and msq to try and help

Thank ya

I wanted to add one more thing, NORMALLY, the injector light flickers when the car is starting and running, then the center (wue) is usualy on till it hits the temp thats needed. But when it stalls, the injector light doesnt flicker till I reset the power to the ECU. Also, I have never seen the third light on, only the injector and WUE has came on so far.

From reading that, alot of it has to do with assembly issues and a little with the firmware. But when I bought it, it was pre-assembled and Im sure they did it right.

This looks like a firmware corruption issue to me as well - for example, there's some rather strange behavior with the MAP sensor signal. However, if that does not pan out you may also want to check the wiring to the HEI module as it seems like there may be a problem with the RPM signal dropping out. As corrupted firmware can cause this, though, I'd reflash it first.