new evo 4 owner wierd cut out :/

[Megahurtz]

Hi there im a new evo(4) owner and therefore new to the forum, so please don't be too hard on me
i've recently bought myself a black evo 4 and its been great fun so far, but i have a small problem an wondering if you bigwigs can help.

Sometimes when im fully on the throttle in 2nd and 3rd gear up to around 6krpm it cutsback short of hitting the redline. However it will redline in 1st gear fine everytime without issue ?

I changed the sparkplugs to some ngks and the problem still persists, so perhaps it might not be them.
I could buy some new ht leads but were told they were new silicone ones when i bought the car.
Coils i guess could also be an issue ?

As a last resort im gonna have to go to a garage an pay them to hook it up to a machine an see if that can help. Maybe air/fuel ratio ? The list goes on...
The car itself has no major mods just an hks airfilter and aftermarket exhaust.

i dunno guys im just stumped an hoping you guys can shed some light on it.
Thanks

 

[DDS789]

Sounds like boost cut

Where are you based?

Ideally want simon@NTS to get involved.

 

[Megahurtz]

sorry im based in torquay in devon so everywhere is far away lol. i bought the car in suffolk about 2 months ago

 

[fq-craigus]

Fuel cut. Needs mapping

 

[DDS789]

Fuel cut. Needs mapping

That what I meant lol, knew what I was saying didn't sound right.

Will need mapping but the 4 ecu isn't mappable have a look at the tuning advice at the top of the "technical" section

 

[Megahurtz]

ah ive looked into that.
theres a evo 5 ecu on ebay for £200 ah well at least its an upgrade i suppose, ill have to upgrade the injectors also then.
thanks very much for your help guys.

 

[fq-craigus]

What mods has the car got at the moment. Is the boost above stock?

 

[Megahurtz]

hi, as far as i know its a standard engine with the limiter still on(verified)
its got exceedy clutch and flywheel.
hks air filter
3" turbo back nur-spec stainless steel exhaust with a 4" nur spec backbox
de-catted
silicone ht leads with ngk-r spark plugs
rear transmission is from an evo 4rs with a 2-3/4 locked diff
and a turbo tim boost gauge.

theres nothing in there that can manually adjust the boost to my knowledge
( however small that is :/ )

 

[DDS789]

It's the air filter and exhaust combo.

The are just helping the car breath better, it's pretty normal for it to happen.

Get yourself the ecu, sometimes there's the apexi ones forsale too which are good.

You just need to factor in the cost of the ecu, plugs and remap. It'll be well worth it once done, you won't be disappointed!

 

[russ-5]

You may want 560 injectors too

 

[Megahurtz]

Brilliant thanks for the swift replies. I'll get the pennies together and get right on it.

 

[Megahurtz]

Alright guys just a note to let you know i went to Alan Jefferies in Plymouth the other day for a remap. Turned out it was the actuator that had sized(common problem- water through the vents apparently) and was overboosting. Luckily he had a new one around and put that in. However the fuel pump had not arrived in time so hes put it up to 292.9hp on the rolling road but wont go above that till the pump (walbro fuel pump 255) is fitted next Tuesday. ill post the results once i get them. Once again thanks all for your help

p.s it has been costly, in total £752 inc vat
£420 for the remap + rolling road
£42 actuator
£50 labour
£90 fuel pump
£150 labour to fit it - taking the tank out to fit - not cutting the hoses

But im sure it will be worth it

p.p.s for those who want to know i found my evo 6 ecu and injectors off ebay around £80 each so that wasn't too bad