just got in my evo 8 ecu and 399 maf and im idling a little rough, would this be an injector latency value or maf table?

on cold start up it wants to die, and it seems as well like sometimes when i come up to a stop light or stop sign and dont downshift at a reasonable distance back it dies as well.

i think its an injector latency, but i need other opinions on it as well.

i will data log tonite hopefully and post up as well, both in boost and not.


josh

 

Did you let the car re learn the idle after you disconnected the batt? Dont forget about that

 

yup yesterday and then took a 20 min drive down to school about 4 hrs after that and the 20 mins back home last night from school.


josh

 

I know it took mine like 2 days before idle went back to normal. Easy to check your injector scaling though just log fuel trims

 

injector scaling, maf scaling, the other maf scaling also (forgot what its called)

i hate tuning this part...

 

smoothing table

 

Dont forget about maf sensoring filter and maf size

 

yup well i kept the same 399 maf that the ecu is used to so thats why i think its more of an injector issue than a maf issue, but hey ive only been driving for a day now so ill see what happens, just gotta get out and datalog it.


josh

 

Ya thats true forgot about that, I do know my 05 ecu had settings for everything alot different than the 03 settings I used after I went back to my stock ecu with the 399 maf (still working on getting another ecu). Seemed I had to bump everything up alot in the maf scaling too. I realized my maf scaling I had for my stock maf was wayyyyyy off which was why I was only hitting maybe 95 load. Now I am hitting 110+ load

 

ya i really think its an injector thing. at normal idle im at 10.7-12.5!!!! thats way too rich for idle and it seems a little like it wants to hesitate a bit obviously after that and need to clear out the system.


josh

 

Wow man that is rich!!!!! I was idling too lean to register before I bumped my scaling up on my maf, now jumps around 15-17

 

You need to look at your fuel trims to know where your injector latencies need to be adjusted. They will tell you everything you need to know.

 

yupand thats all done with evoscan. i just havent had a chance to do so.

josh

 

4th reply

 

ok so it looks like my trims are:

low .1008
mid range -7.351 to -10.0964
hi .1008


now to adjust. but which way to go?


josh