I'm posting this video to get feedback on if my 05 EVO's start-up tune/settings can be improved upon.

The car is equipped with AEM EMS, AMS 50 trim, and Precision 1000cc injectors.
I know idle can be improved upon but I wonder if the start-up can be improved also... Thanks !

 

Thats weird how it oscillates like that....I am sure there is something that can be done.

 

my friend's eagle talon is worst than that, and I told him w/ more tuning it could be better. He can't even drive the car w/out warm up.

 

But I know few people w/ the AEM EMS, cold start idle was never smooth... that's why I will go w/ HKS F-CON V-PRO, it starts up just like stock no need to crank it for 2, 3 secs.

 

Yeah, but who around here can tune the HKS F-CON??

 

when i first start up the car when its cold, it will idle around 1.5K rpm until its warm up. I had the stock injectors though... i think its normal for most of us AEM EMS users.

ps: when winter comes, its worst!

 

Ok, so in the video we can see that after the engine stops oscillating it stabilizes around 1500 rpms smoothly till it gets fully warmed. Fully warmed it idles around 1000 rpms or so.

Anyhow I'm taking the car back to get my low-end part throttle maps looked at, and I'm also gonna have my idle lowered a bit...

 

Go to

Engine Start>Advanced Start>RPM Offset vs Start Table

lowering that graph should help.

 

Help with the oscillating/jumpiness at start-up right?


I'm also lowering idle so that my exhaust note wont have to be so loud at idle when I'm parked or at a red light

 

How well is your idle% vs. Target table setup?

 

I wouldnt know....my tuner tuned the AEM...

 

another reason why the ems is not suited for certain users, this really isnt a 'set it, and forget it' system, SOME user interaction will be required!

 

It just takes some time to tune it, but once it's tuned, it's tuned!

 

I haven't seen the video yet (at work) but my car starts up from a cold start without a single problem. (Lowest i've started it was about 28 degrees) I spend some time tuning the startup though. I know on my 03 with the original idle air control valve it won't allow adjustment above 1550rpms for idling. AEMPower stickied my post of this in the Evolution section of the forum. If your cold start is trying to go above this it will cycle badly till it warms up.

This cycle can also be seen if you rev the car once it is idling correctly, it will cycle 5 6 times and begin to settle.

2004 Evo's got a new IAC motor, and there is a part number change. The new IAC motor has a more range of adjustment as it moves more than the original my car came with. I do not know however is the newer IAC motor has this problem as well as I have never tried to instigate the problem.

Without seeing the problem, I can surely tell you you can have an AEM tuned car that starts very easily even in the cold. Just may take 3-5 cranks which is nothing considering the power the EMS gives you in tuning anything.

 

after you get a chance to see the video please report back