Ok, first, I know, I should have put effort into getting the megasquirt to work. But I can't figure the damn thing out (either how to program it or what the heck is wrong with it) and had gotten sick of dealing with it, so I bought the AF/X recently so I could do SOMETHING about running on a stock ECU. (yes they carry them for all years now it seems)

Anyway, this thing is killing my battery. Car has a new optima yellowtop, new alternator, no parasitic drains (about 36-40 milliamps draw, well within normal range, with the stock ECU in the car).

With this AF/X ECU, I had a multimeter hooked up in line with the battery and when I turn the car to "on" and energized the system, the ECU hums (hard to hear it, it's high pitched) like I'd expect it should, and the current draw is about 2 amps.

After turning the car off, it's still humming and drawing 450 milliamps even after 20 minutes, definitely enough to kill my battery after 3 days like what has been happening. Pulling the connectors on the AF/X ECU dropped it to about 40 milliamps and no more electronic hum. Definitely the ECU. Probably not the 13 year old alternator I replaced x(


Doing the exact same thing with the STOCK ECU (I knew it was wise to keep it), after turning the car to "on" then off the current draw is... 40 milliamps.

Anyone ever have one, and have this kind of problem with it? I sent Howell an E-mail, hopefully they will be agreeable and look into this. They provided the core, maybe they got a bad one, maybe the programmer messed up, who knows at this point.

This thing hasn't been al it's cracked up to be so far ;(

Oh, raced with it at the track, only hitting about 7500 rpms red line, don't know if that is normal or not. Raced on a cold day with it, no traction, so it was a bad day for a comparison. Car seems to drive around normally with it and idles fine, but I can't tell so far if it's actually helping, so I'll reserve judgement on it.

Interesting stuff, Todd.

I've been running my AF/X ECU for several years now and have never noticed an issue like the one you describe. I did have an issue with a battery being dead after a day of not driving the car, but that was due to an old battery on its last leg. I am curious however on the draw. When I have a DMM available to me I will check this out.

When you simply unplug the ecu there are still a lot of circuits to test that you are taking out of the loop. What happens when you pull different fuses. Pull them one by one until you find out which circuit the ecu is keeping engaged. You still may have an ecu issue but when Howell writes you back you will have another leg to stand on against there claims or something.