Stock ECU Tuning Info ...

[TouringBubble]

Hi everyone ... I just thought I'd drop in and offer my knowledge to the community here on EvoAtlanta. If you have any questions regarding tuning the stock ECU, I'm here to help answer them. If I can't help, I'll do my best to get you the answer you're looking for.

So, ask away ... P300 issues, Tephra Mods, map scaling, O2 fixes, EGR deletion, tuning recommendations, ROM updates, basic advice ... I'm here.

:)

[ultm8mind]

welcome

[TripperFx3]

I actually need help with my O2 deletion. Someone else on here was going to help, but I've just been lazy and need to pull my ROM. I currently have an old method of removing the rear O2 via ECUflash, but it doesn't pass readiness checks, so it won't pass emissions.

Welcome too!

[TouringBubble]

It's my understanding that the basic rear O2 deletion mod (Mrfred/Tephra patch) won't let you pass emissions just as you've stated. You'll need to disable the check itself using the periphery bits which are not completely defined yet. Mrfred is working on them, but mainly for the Evo IX. You can follow this thread (http://forums.evolutionm.net/showthread.php?t=366879) to see if anything useful for your ROM pops up.

[blkonblk2red]

this guy knows his s*** :-D welcome :-D

[TouringBubble]

I received a PM with some questions and I thought I'd share ...

Can you explain what the loads stand for on a fuel map and also where should i start first when i start tuning.

There is some debate about how the load values are actually calculated. The basics are that 100% load is 0 in/hg (or psi). Anything above 100% is in boost and below 100% is vacuum. The more boost the higher the load and the more vacuum the lower the load. As you drive you will hit many different load areas. Changing the efficiency of the engine/turbo system can also change load values ... for instance, larger cams generally produce higher load levels.

To get started I'd suggest reading through the tutorials on the recently created Evo Tuning Wiki (http://evoecu.logic.net/wiki/Main_Page). Here a direct link to my tutorial (http://evoecu.logic.net/wiki/How_to_...o_TB_Alternate) ... it's not complete yet, but I still think it's a great resource.

[1badevo]

yeah i got a Q i hooked the comp. up to my evo and it says its running lean. but i do have a cat delete. woud that mess with my o2 sensor if so, what could i do to fix that prob and how much would it cost

[TouringBubble]

What reading are you seeing that is showing a lean condition? Also, when are you seeing the lean condition? Idle? WOT?

Removing the cat shouldn't affect the fuel mix since the ECU only references the front O2 to determine fuel delivery. The rear O2 is only for emissions and is compared to the front to determine how well the cat is functioning. The only way removing the cat could affect the mix is if a trouble code was triggered ... and that will usually cause a rich condition, not lean.

[tvrvic]

It's my understanding that the basic rear O2 deletion mod (Mrfred/Tephra patch) won't let you pass emissions just as you've stated. You'll need to disable the check itself using the periphery bits which are not completely defined yet. Mrfred is working on them, but mainly for the Evo IX. You can follow this thread (http://forums.evolutionm.net/showthread.php?t=366879) to see if anything useful for your ROM pops up.

This isn't true and is actually backwards. Disabling the periphery bit will cause the Check not to run thus eliminating the CEL but not allowing the OBD2 readiness test to ever complete.

By using the Latest MrFred/Tephra patch the periphery bit remains enabled and the only thing the modification does is send the data from the actual o2 sensor(or none at all) to a different area in RAM and place valid data where the ECU expects it to be so it believes the O2 sensor is functioning and reading. To eliminate the CEL and pass ODB2 readiness tests you will need to place a resistor between the heater wires along with the ECU code modification.

[TouringBubble]

Good info ... thanks. I don't personally use the rear O2 delete mods so I may have been confused. I was under the impression that the newer Mrfred fix was basically identical to the original resistor fix that did not pass emissions.

[bomjoon]

whats a tephra? is that a new type of tempura? i have not tried that. lol

what up bubble.

this guy tuned my car numouros times and he amazes me everytime.
he gets me powa where i want it.

+1 for his face~!

[1badevo]

well all i know is thas all ive done to the car and now it says its running lean bad. but thanx yall

[bomjoon]

you might want to get that thing tuned if its leaning out.

leaner isnt always better...

[TouringBubble]

well all i know is thas all ive done to the car and now it says its running lean bad. but thanx yall

We need to know how you are getting the lean reading ... do you have a gauge? Is it reading the stock sensor or an aftermarket wideband sensor?
Are you using a computer? If I know this I may be able to help.

[bomjoon]

he has a sound gauge. he hears knock. lol j/k

[1badevo]

no and its stock

[TouringBubble]

no and its stock

Alright, I'm trying to help but I need more info. You say the car is lean, but I need to know how you are getting the lean reading. What method are you using to monitor the AFR?

[1badevo]

well all i know is that i took it to advanced and they hooked it up cause i just wanted to know why my check eng lite was on

[TripperFx3]

And what did advanced say? Lean condition?

[TouringBubble]

It sounds like it threw a code for a lean condition. Has the code come back?

One thing to consider is that the car can only read the fuel mix at idle/cruise conditions. Once you roll in to the throttle the ECU could care less about the fuel mix and relies only on the values in the maps. So, it's likely that you are rich at high throttle and it was simply that one circumstance that tripped the code that said you were lean.

If the code hasn't come back I wouldn't worry about it.

[1badevo]

ok thanks bud