-= Ultimate Emanage Tuning Thread =-

[BlackStealth]

Originally Posted by archangelcomp

Its rather weird though...sometimes it idles ~11, sometimes it 14-15 where I want it. I just tried leaning it up a bit, shot to ~16. Its not really doing stuff thats all that predictable...so I'm a bit lost as to what to do.

It's normal for the car to run rich when the engine is cold but once it's warmed up the AFR should be around 14.7 AFR. How does your WB02 datalogs look like? If it flucuates like mad then you may have noise on your WB02 output wire (caused by the antenna effect and can be cured with a small capacitor). 16 AFR at idle occurring occasionally isn't nothing to be worried about, but more importantly does your car still run fine at part throttle and WOT AFR numbers are still okay.

[Elina75]

Originally Posted by archangelcomp

Yeah, I know that much. Sometimes its good and chills around 14-15, then after its been running for a while it idles rather rich.

Oh, and did I mention I'm getting like 9mpg?

Ah!

Do your fuel trims (low) go down when it's goes to rich idle?

[archangelcomp]

Originally Posted by Elina75

Do your fuel trims (low) go down when it's goes to rich idle?

I'm not sure actually, I'll check that.

Also, the AFR doesn't fluctuate like mad. It does a little bit, but its not hopping all over the place. At WOT I'm getting ~11 and that seems consistent. Little to no knock to speak of.

[Dj_Frost]

Hey guys, when I let off the gas in gear, shouldnt my AFR go to like 20 something? Because the injectors are supposed to turn off or just go to 0% duty cycle.

And when I have my key to the ign on position, should my fuel pressure gauge read 44psi? Cause its reading like 18-20.

[Elina75]

Originally Posted by Dj_Frost

Hey guys, when I let off the gas in gear, shouldnt my AFR go to like 20 something? Because the injectors are supposed to turn off or just go to 0% duty cycle.

And when I have my key to the ign on position, should my fuel pressure gauge read 44psi? Cause its reading like 18-20.

Depends on what year yours is. Earlier models don't turn the pump on until you actually crank/start the engine. At idle, vacuum disconnected you should have 3 bar, 43.5 psi.

[Dj_Frost]

well mine is a 94 but its styling is 93 and most of the parts (5 speed) are also from first gen models.

I have it set at 44psi using the AEM FPR. The thing is, I thought that before cranking the engine (having the key on the "on" position) the pump should be running and the pressure up to 44psi as well.

And what about when cruising and having the car in gear but not pressing on the gas, shouldnt the AFR go like to 20 or over cause the injectors are now off?

[BlackStealth]

It's pretty easy to tell what your fuel pressure should be at all times just add or subtract the boost. For example if at idle you're at -10psi (vacuum), then you should read (44psi-10psi=34psi).

When I take my foot off the accelerator I normally observe a momentary rich condition just before it heads to 20 AFR, and yes the injectors do turn off during coasting.

Non-turbo cars prime the fuel pump but twin turbo cars don't. I've confirmed this on a 93 and 94 twin turbo. I have no idea why mitsu would design it like though.

[archangelcomp]

Alright, so I got some balls today and tried to tune my car a bit. Here's a 1st and 2nd gear pull (not to redline) with my DSBC set at ~21psi. Datalog: http://www.archangelcomputer.com/3si...7_17_57_29.xls

And holy hell, does she go like a frigging raped ape. I'm still having the incredibly rich idle after I drive though. Just driving normally, park somewhere, let it idle in neutral and my AFR reads right around 11. I've waited to see if it goes back up, but it doesn't. Not too sure I understand that.

[Dj_Frost]

Originally Posted by BlackStealth

It's pretty easy to tell what your fuel pressure should be at all times just add or subtract the boost. For example if at idle you're at -10psi (vacuum), then you should read (44psi-10psi=34psi).

When I take my foot off the accelerator I normally observe a momentary rich condition just before it heads to 20 AFR, and yes the injectors do turn off during coasting.

Non-turbo cars prime the fuel pump but twin turbo cars don't. I've confirmed this on a 93 and 94 twin turbo. I have no idea why mitsu would design it like though.

Hmm, I understand how FP reacts with boost but what I'm still confused about is before cranking it. When the key is to the "on" position, is it ok that I'm at 19-20psi of FP or should it be at 44psi like it is on idle when I turn it on?

And when I take my foot off the accelerator I dont see it go to 20 AFR, it stays at like 10-12 so i've def got something wrong going on.

[BlackStealth]

archangelcomp: Your sample rates are very low on that palm datalogger, you might consider reducing it to RPMs, Knock, TPS, o2 front, o2 rear so you can get more samples. The narrowband o2 sensors agree that you're running rich only after a long idle. Your fuel trims are normal so it's not like you're past the ECU's fuel trim window. Any reason you didn't pick the emanage datalogger? It would be nice to see wideband AFR results and much faster sampling rates. Both o2 sensors read high so if you had a defective fuel injector there would have to one on each bank. Secondly is it possible your FPR is overrun at idle?

Originally Posted by Dj_Frost

Hmm, I understand how FP reacts with boost but what I'm still confused about is before cranking it. When the key is to the "on" position, is it ok that I'm at 19-20psi of FP or should it be at 44psi like it is on idle when I turn it on?

And when I take my foot off the accelerator I dont see it go to 20 AFR, it stays at like 10-12 so i've def got something wrong going on.

It doesn't matter what your fuel pressure is before cranking. My fuel pressure drops to near zero after many hours of no use and during cranking the fuel pressure is restored and the car starts up normally. Also if your fuel pressure is 44psi at idle then your base fuel pressure isn't set at 44psi.

Use your emanage datalogger to verify your injector duty cycle or pulse width goes to 0 after coasting in gear with no accelerator.