ECU Possibly going bad?

MI-4 EVO · Oct 5, 2009, 05:43 PM

Had the AEM in the car for over a year now, no problems. Car sat in the garage with the battery disconnected for 6 months while I was over in Iraq. When I got back I put the map back on it and it ran just fine for a couple of weeks. Suddenly it started dumping a ton of fuel (to the point where it will flood itself out) and I would have to upload the tune again. It's happened several times now in the past 2.5 - 3 months. Last time it wigged out on me the fuel gauge started reading wrong. It reads almost half a tank low. I checked everything out today and nothing appears to be mechanically or electrically wrong with the car. I plugged the stock ECU in and the fuel gauge reads right and it threw no codes despite all the mods (did NOT try to start the car). I'm thinking something has gone wrong with the AEM.

Any thoughts?

Oh, and I downloaded the map from the ECU before uploading it again and did a compare. Nothing is different. However, uploading the map cleared up all the problems (with the exception of the fuel gauge) for now.

Femi · Oct 6, 2009, 10:10 PM

Are you sure that you are not running into corruption issues with the map? Perhaps take a fresh basemap, and then copy all of your settings over to it, load that, and see how it runs?

dhammans · Oct 8, 2009, 11:25 PM

The AEM ECU's die quite often. Sad, but it's the reality. Best to call AEM for warranty work if you're still within the warranty period.

MI-4 EVO · Oct 9, 2009, 08:00 PM

I have heard of the AEM EMS going out before. I called AEM tech support. They were not helpful and quick to blame an electrical problem with the car, which I've reasonably ruled out.

I've already loaded two seperate cals to the ECU as suggested before.

GTVEVO · Oct 20, 2009, 07:40 AM

The only thing I could say here is re-flashing or changing the actual firmware on the ECU incase there is any internal software corruption. Sadly AEM support seems to act this way quite often.

I agree you do have an issue and I would recommend not driving the car very far or hard without doing some more testing. To bad you don't know someone else around with the AEM to do some additional testing.

MI-4 EVO · Oct 20, 2009, 07:09 PM

I tinkerd around a bit with it this weekend, built a completly new cal, updated the firmware, no change. but, the car hasn't gone loopy on me in a few weeks either.

I was looking to see if there was a way I could turn each output off individually to see the effect on the guage cluster. Looked around a bit but didn't see any options. anyone know if this is possible?

awdboosted · Oct 25, 2009, 10:12 AM

Can u post a log when the issue is happening.

MI-4 EVO · Oct 25, 2009, 08:55 PM

Quote:

Originally Posted by awdboosted

Can u post a log when the issue is happening.

If it happens again I will.

Ever known the AEM EMS to throw off the fuel gauge?

itzwolf · Oct 30, 2009, 08:52 AM

Quote:

Originally Posted by MI-4 EVO

If it happens again I will.

Ever known the AEM EMS to throw off the fuel gauge?

Yes, there is a pin that you can pull from the plug harness to correct this issue. It's a commonly known quirk and makes the fuel gauge read about an 1/8 of a tank lower than it really is. I've dealt with it for the 3.5 years I've had AEM in my car.

I think it's been noted on these forums which pin to pull but it really doesnt have any other side effects so I wouldnt worry about it. Worst case you fill up a little sonner than normally and have less chance of running out of gas accidentally.

dhammans · Oct 30, 2009, 08:58 AM

(A)lmost (E)ngine (M)anagement (!)

badhabit90 · Nov 2, 2009, 09:09 PM

Quote:

Originally Posted by dhammans

(A)lmost (E)ngine (M)anagement (!)

THIS!!!!!!!!!!!!!

HAHAHAHHA

: lol:

throw it away Herb. ECUflash and git er dunnnn......EVOscan to log ........1/10th the cost and you tune the same way. geez...you dont have a huge turbo, VTA, and your runnning your MAF still plenty of cars hitting 500hp with stock ecu and such...
OH and get the cable also........

so, you have
99 bucks for the cable
20 dollars for the EVOscan when you get the cable at the same time
ECUflash-FREE!!!!!

AEM ECU -1200bones.......and its dying....no support from AEM...boo that noise.

soo, you have 119 bucks invested with the same tuning capability just about with factory knock safety.....logged my tune for 45 minutes..various driving....0 knock under boost.

at 22psi. WORKS tune