another newbie here but need help with my gto

gto400

Full member
Points
16
Location
dorset
Car
mitsubishi gto tt
hi all, first time ive posted on this site and i hope someone might be able to help, i have a mitsubishi gto twin turbo which has been stood up for a while i have finaly got round to getting it all up and running and on the road, ive just put a stage 2 clutch in it from evil empire moted and taxed it, now the problem is its misfireing and kangarooing under load, its ok if your using a 1/4 throttle but as soon as you put your foot down or even half throttle its misfireing under pressure so ive just put on a coil pack and new spark plugs still the same, i gave it a good run still the same, mods are a hks exhaust, decat, filter, hks boost contoller, hks fcd, and a few other bits, has anyone had the same problem or any input as to what you think it might be, any help would be much appreciated thanks.
 
Have you fitted new spark plug wires?

If it has been stored without a full fuel tank it may have had condensation in the tank and the pump is picking up water as well as petrol so my suggestion is that you drain the tank to see if there is water in the fuel.
You should check/replace all the fuel filters including the in tank pick up filter as they can become clogged with rust etc

See if you can test the fuel pump flow by disconnecting the line at the rail and pumping it into a bottle BUT this will not indicate how it flows/behaves under load when it pressurizes the fuel rail
 
thanks for the reply tcjboldie, so far the possibilities are the ecu, fuel relay, boost leaks, or as you said it may be condensation due to being stood up for a while, im just trying to get all the possibilities on the table so i know where to start, i forgot to add it revs perfect when stationary, but thanks for the input
 
Was the car running fine before you parked it up?
Is it a digital boost controller? If so has it reset to standard settings? I'd also be checking the fcd setting and wiring cause it's job is to cut fuel

I'm only suggesting simple things cause these are usually overlooked;)
 
thanks herb any input is helpfull as its got to be something doing it, yeah its a hks digital boost controller to be honest i havent even looked at the boost controller as thats how i burnt the clutch out in the first place, it started misfireing a long time ago and i got pissed off with it set the boost controller to max took it down the bypass and goodbye to the clutch, so now with only 50 miles on a new stage 2 clutch i dont realy want to be putting the boost controller on, but i will have a look at the fcd and trace any wires, you never know it might be just that.
 
thanks herb any input is helpfull as its got to be something doing it, yeah its a hks digital boost controller to be honest i havent even looked at the boost controller as thats how i burnt the clutch out in the first place, it started misfireing a long time ago and i got pissed off with it set the boost controller to max took it down the bypass and goodbye to the clutch, so now with only 50 miles on a new stage 2 clutch i dont realy want to be putting the boost controller on, but i will have a look at the fcd and trace any wires, you never know it might be just that.

Do you have a boost gauge?
 
Greetings gto400 and a Warm Welcome to our TorqueCars Forum my Friend!

Good to have you along with us :)
 
thanks t9 man good to be here buddy, and yes its got a boost gauge

What are you boosting atm? Cause I'm I'm leaning towards this being your issue cause if you have your controller turned off it maybe over/under boosting and the engine is protecting itself
 
i think thats standard boost with the boost controller on i think it was around 0.9 - 1 bar of boost
 
well it sounds like you're air and fueling are out and the ecu is going into limp mode to protect itself
I'd firstly try and get your boost controller working correctly;)
 
leave it with me boys and through the week i will have a good look into everything and see whats what, ill be back ;)
 
Finding and fixing a miss type problem can be very frustrating.

My son wanted to know what time the JB would do on the 1/4 so while driving to the strip I had a premonition that something would go wrong so lined up for the first run and there was some vibration on take off and at the end it was sounding like a WRX on 3 cylinders , no smoke ,temps ok ,oil pressure ok.

so drove home on 3 .Pulled plugs looked ok ,compression test all between 165-170 psi,installed new plugs,had dinner then started car and it ran fine so went 4 a drive and app 3k down the road the miss returned so I reasoned that it was temperature related and maybe a sensor that was defective,back home tracked it down to #1 cyl so not the EMS as it runs waste spark so must be #1 coil so replaced #1coil, starts up on all 4 Problem fixed ??

On next test run starts missing a couple of k's again GRRR. installed new/spare wires, no change,swapped #1&2 coil wires along plug leads, still no difference, maybe it is the injectors but can hear them clicking with long screwdriver in ear,pulls injectors and had them sonic cleaned etc reinstalled and miss starts straight away .

bingo!! tested power to injectors and zero to #1 so wriggle wires and all 4 running hip hip hooray traced it to a faulty joint in the injector harness had sparky replace it and all smiles again.
This can be very frustrating and character building.

FWIW I did a 14.3 so must see what it can do on all 4
 
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who around here is best with ecus as a few people have also said about the caps leaking is a common problem, so today i took the ecu out and had a look, the ecu looks perfect the caps are not leaking but there is a slight whitening in places, i dont think its anything but i took a few pics anyway, i can send them by email if anyone needs to see,
 
also checked the wireing from the fcd boost controller and injector wires, the best i can without a electrition anyway, does anyone know where the fuel relay is.
 
i dont think its anything but i took a few pics anyway, i can send them by email if anyone needs to see,

Your on 9 posts now buddy, once you have reached 10 then your name will be printed in bold lettering and you will be able to post those photos yourself in your posts ;)
 
i would say it was ecu as i had similar problem with mine
its the most common problem with gto,s, the capacitors leak and wreck the board, remove it and open it up and if it smells of eggs its leaking
hope this helps
 
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