Hi All,

Trying to get a better understanding of how this all works and hopefully take the final steps in finishing off my build.

I live in a state that is not so lenient with emissions...

With that in mind.. I wanted to know if it is a viable solution to swap between an aem infinity & stock ecu purely for smog/obdii purposes...

I'm not sure of the level of effort in embarking this or even if it is feasible to introduce an aftermarket ecu...

I have my reasons for the aem infinity.. flex fuel being one of the primary reasons... but come emissions time... what is involved with swapping back to the ecu to get checked out and popping the aem infinity back in?

 

I plan on going with a AEM and using my stock ecu for emissions also.

From what I've read/understand, the stock ECU will need a base map for the current parts installed(SD/MAP/Injectors/Fuel). 2 wires from the stepper needs to be remove for the AEM and needs to be reinstalled for the OEM ecu. I don't think you can run a 12tooth trigger disc on the stock ecu.

If the main reason you're switching to a AEM is for flex fuel, why not just do flexfuel with the stock ECU?

 

Thanks for the response!!!
The 2 wires in question... i've already got the OG boomslang harness that i can keep attached to the stock ECU... the pnp harness for the evo to the infinity can deal with the de-pinning from my understanding...
I'm like 95% positive that we can't run the 12tooth trigger disc like you've pointed out...

if that's all there is to it... i think I can be well under way on this new adventure for my build...

and reasoning is not only flex fuel... but on the fly map switch (boost control)... proper launch control (including rolling launch launch control)... as well as proper tuning... due to travel... i change elevations anywhere between 56' all th eway up to 5280'... figure the aem infinity is the best bet to assure everything's running perfectly...

i've read a bit as far as stock ecu+flex fuel... i haven't seen a definitive result and my local tuner who I know and trust do not offer that.

 

You are correct on the 12 tooth trigger wheel not working on the stock ecu. For most aftermarket Ecu's its nice to have the 12 tooth trigger wheel for more clarity.

That means pulling the front cover each year to swap back to stock components for the emissions test.

 

Are you sure you still need to plug in? Massachusetts is one of the strictest emissions states in the country but we have a 15 yr rule where cars are exempt after that timeframe.

I used to play the parts swapping game but didnt have it that bad. Swapping the trigger wheel sounds annoying. Youre pulling lower cover and doing a timing belt job twice a yr essentially. Built motor, hopefully have an ATI damper on there and now you have to pull off that mandrel as the trigger wheel is behind that. Dont get me wrong I can bang out a timing belt job in a few hrs but your question was if this is viable and while technically it is, you're going to realize its not a great plan in the long term.

 

Can the wheel be mounted/welded the to crank dampener so you have both signals available and not need to swap?

 

You could just move into a MoTec on the stock trigger wheel. Plenty of cars out there running it.. Well.

 

You'll need to remove 2 pins from the IAC connector.

 

But you can't swap back oem ecu for smog checks without swapping back oem trigger.

 

If I still had an o2 sensor in my o2 housing, I could go from running on my AEM to stock in about 5 min. As others said, its really only the IAC wiring that you have to change.

 

this looks like a custom adapter harness is in order... which can't be that hard to source/make.. i believe the iac plug is the same as the standard lancer

 

Incorrect. JRR has a package for the stock trigger (Myself and plenty of Rally cars are using it) Or a 12 tooth trigger .

 

External trigger wheel is possible with proper engineering, but it's a lot of work for minimal gain.

I've thought build an electronic circuit to simulate a stock trigger wheel signal from a 12-1 sensor output. That would allow swapping back to the stock ECU temporarily with a 12-1 wheel. If I pull the trigger on an aftermarket ECU I'll look into it.

 

Cool. Do you have a link to see how it's installed?

 

Lingenfelter makes something like that for the LS engines. Lets you install a later model 58x engine into a vehicle that uses a 24x ecu. Dont see why it wouldnt be possible for someone to make one like that for the Evo.