My car used to be tuned with AEM. My AEM took a dump and had to send it in. When i bought the car I never had a copy of the tune. Now its running on a basemap, running very rich but still drivable. I do not drive it.

My question, is it worth converting back to stock ecu? I belive my car is in an Open loop setting because the front o2 is cut. The TPS is unplugged, and when I plug it in with the AEM the engine goes to redline.

Next question, If i do convert back to stock ecu, my evo's bov is uncirculated. Its a suck through setup. Would I have to switch my BoV to recirculated, or can a flash correct it.

 

Leaving out the issues with the AEM which include that mess with the going to redline you should be able to tune it just fine using the stock ECU. It'll run just as good if not better.

There ARE people doing speed density with the stock ecu but i don't know how solid that is. If you're running a blow through MAF that's after the BOV you should be ok. What MAF are you using? Perhaps a MAF-T might be in order but i'll bet someone's got that figured out in the stock ecu too.

I'm new to the stock ECU tuning thing but not new to the AEM EMS at all. It's a nice system but so far i have had better luck with the stock ecu than with the AEM though it was on a different car.

Either way i would get it running properly with the front 02 and the TPS before deciding on a solution.

 

Thankyou for the responce. I bought the car with all the mods listed in my sig. Im very unfamilar with the tuning world but hope to catch on in a timely manner. Right now Im stationed in Iraq and should be home September this year. I really want to get my car running right before the winter hits.

I just picked up a LC-1 with Digital gauge. Im going to replace my AEM uego with it. I also picked up a 1.3u Tactrix cable with evoscan. I had to purchase a stock ecu because my car didn't come with one upon purchase.

I'm hoping the front o2 and tps are the only sensors unhooked. I live in alaska and there are no AEM tuners avalible. Once Im able to pull datalogs I'm going to have mellon tuning tune my car via email.

 

That seems like a pretty solid plan. There are tons of EVO's running around making TONS of power with all the sensors intact. I'm sure you've just got a couple minor gremlens to work out.

The AEM EMS is not really harder to use as much as it's just not quite as good at part throttle, idle, startup, exc exc. With utilizing the stock ecu you get all those things "for free" and you only really have to fiddle with WOT and maybe idle a little.

It's just like anything else. I think for a maximum effort build the AEM EMS might be better under some circumstances but for anything like a daily driver it's hard to beat the stock ECU.