evo viii ecu fuelling problem [Archive] - Mitsubishi Lancer Register Forum

evo viii ecu fuelling problem

05-12-2007, 10:45
hi, ive got an evo viii fq330, ive had a mr320 complete engine fitted to it including turbo manifolds etc.
the car also has a 3" exhaust with decat pipe, hks mushroom filter, and a big hid intercooler.

now the problem; i have had it on a rolling road and it is producing 365bhp :eek: but is running lean at around 5-6k :confused: ,
the obvious thing i thought to do was to knock the boost down, but after putting the boost down it was running lean throughout the whole rev range. :(

i have been advised to install a walbro 255 fuel pump and a new fuel filter, also to get ecu flashed.

can anyone enlighten me on whether this is the right thing to do, and also a recommendation to someone in the midlands area that can ecuflash to get the fuelling correct.

any advice would be much appreciated

Ben 6
05-12-2007, 11:01
pm GrayW mate, he will have all the answers you need :)

05-12-2007, 12:25
Originally posted by fernando_khan
hks mushroom filter,

That could well be your problem. It's been found on many occaisions that a non standard in take setup will adversly affect the fueling. Do you have the stock air box to put back on? Do you have a Tactrix cable yourself?


05-12-2007, 13:09
Do you have the stock air box to put back on? Do you have a Tactrix cable yourself?

i dont have the standard airbox, nor do i have a tactrix cable.

is it worth getting a tactrix cable?, as i am not too clued up engine management.

05-12-2007, 13:26
It's not as hard as you might think, though you will get much much quicker results from a pro tuner. For some one with moderate PC skills and an understanding of engines, a little reading and about 300 for the cable and wideband O2 sensor will see you tuning your own car.

Here's a link to a good thread.


05-12-2007, 15:20
thanks for that burgers, ive had a read through of that thread, makes it look very easy, however i dont think i can trust myself tryin to map it for the first time.

is there any ecuflash users that might be able to help me out? or anyone know of any ecuflash tuners?

05-12-2007, 15:30
I had the same issue on my 330, it seems the piggyback ECU plus induction and exhaust mods can make the engine run lean.

The solution most people go for is to remove the piggyback ecu and get a reflash, which will unlock more power from your engine as well as improve the fueling, so a win/win, really.

05-12-2007, 16:43
If you haven't got the equipment to log your car it might be better to visit a pro tuner in your area, where they can set up your car. It's a nice idea to get a fellow enthusiast to help, but personally unless the user has got at least a Tactrix cable to log the car post remap, I'd be very hesitant about getting involved.


DaveR 83
24-06-2010, 21:36
iam planing fitting pigg back to up it to 330 bhp i have a decat and am still using standerd air box will run lean :confused:

scandinavian fl
25-06-2010, 09:25
Get it remapped instead mate with a few supporting mods you'd get 30+ hp more

DaveR 83
26-06-2010, 11:26
:smthumbupGet it remapped instead mate with a few supporting mods you'd get 30+ hp more

but i bought the piggy back because i was on a bugget