Haha... you said you have done a boost leak test with an air compressor m8? It sounds like you're hitting fuel cut which will happen if the car leans out too much, so maybe you're boost is turned up too high, or you're having fuel issues somewhere along the way?

This may also explain why the plugs in the motor were so cold. This motor was likely modified with a significant tune, and put back to stock to sell. Did you buy it private party, or from a dealer? The private party may have some insight? Otherwise, you'll need to take it to a tuner and have them sort it for you?

 

iv never done a boost leak test don't have compressor. and my boost is stock around o.7 0.8 bar. your its just strange as it was going really well then just stated nearly cutting out also sometimes the turbo timer just turns of when on?

 

I would suggest getting rid of that turbo timer as its just another variable that is obviously not working properly. Once you have the problem sorted, you can reinstall it correctly and know that it isn't fubaring everything.

Also, just because your car is making its stock boost doesn't mean you don't have a boost leak.

The turbine doesn't care how fast it spins, because the wastegate is controlling it based on pressure. In your case, metric BAR. So if there's a leak, the turbine won't actually "know" and will just spin faster until it overcomes this leak and the motor receives as much boost as it knows its supposed to. At this point the wastegate will open and prevent over boosting.

On top of that, if your vehicle was modified, and returned to stock without changing the tune, the motor may actually boosting at a completely improper level which is causing the roughness.

You can realistically do a boost leak test with a bicycle pump, though with a leak, it will be very difficult to actually do that.

I'd suggest finding someone with a compressor and a boost leak tester, or getting one yourself. Pressurizing the system to around 1 bar, and listen for leaks. Find them (you WILL have them, whether they're causing the problem or not) and fix them. THEN spray every connection with soapy water and SEE if you have any still, and repair those. Reset the ECU again, and see where that gets you.

 

hey man thanks for the help hard to find anyone who really cares these's day's. i can here when car is running a leak somewhere behind the throttle body just hard to find like you said without doing the boost leak test im going to invest in a compressor maybe this week. and i do agree with what you said about the turbo as it will no matter what make up for the diffidence in boost as the waste gate opens. i will keep you up to date on this. on i noticed that the needle on the boost gauge is now jumping up and down again. it was not doing that when i first done the spark change and reset. so im guessing there is a leak somewhere could even be a intercooler hose as they have done 108ks now

 

Yeah m8, no worries. Many people upgrade their piping couplers with silicone couplings. I'm sure you can find a local supplier, but in the states one popular one is siliconeintakes.com. I'd also recommend using some t-bolt clamps instead of the stock worm gear clamps. There's a kit and a diagram on that site, but only for the newer evos. They also sell boost leak testers so you can see what they look like and make one yourself if necessary.

The throttle body shaft seals on the Evo 4+ are generally regarded as leaky. So that could be it. Mellonracing.com is a tuning outfit here in the states that actually handles a fair amount of 5th gen Evos (4-6) so they may be able to offer some assistance with tuning or replacement uprated shaft seals if you can't get them in AUS. Though I'm sure someone has to have something there.

Have you popped onto lancerregister at all? Perhaps one of those chaps can lend you a hand if they're local?

 

yea i have but have not put a post up yet but theres alot of reading haha so ill keep looking

 

Good luck m8. Keep us posted!

 

ok another update, took car out yesterday morning drove sweet as no problems. started it up around 530pm and started to splutter and **** then engine light came on and wouldn't go of so i turned it of and took other car. my partner put car in shed and the engine light as of again? very strange!!!

 

What code is it throwing?