Seeking help on turbo boost

[kurt_629]

Hi,
Need some help and attention over here.

I have a 4g63t, evo 3.
Everything was stock.

When I bought it 3 years back, I have spent time and money to restore it back to stock.

I have replace almost everything that I could possibly think of.
- wastegate
- 3rd fuel pump
- spark plug and cable
- 3rd manifold
- double layer radiator
- boost leak test
- ecu check
- air flow sensor check

The boost now, can only reach 0.5 bar and will cough when I exceed 120km.
Should I unplug the air flow sensor, the boost can goes up to 1.0 bar
With air flow sensor, only 0.5bar

Has anyone encounter such issues?
What could possibly goes wrong?
I have visited 5 workshop but none can resolved this.

 

[kymanhalim]

Dear sifu please help him.. seem like he kena conned by his mech omg...

 

[kurt_629]

Dear sifu please help him.. seem like he kena conned by his mech omg...

thanks, mate.

conned or not.. what is done, is done..
but this car.. the amount of time and money spent to resolve this, is really a pain.

I feel so close, if I can resolve this boost issue, everything gonna be perfect.

 

[y2188]

Hi,
Need some help and attention over here.

I have a 4g63t, evo 3.
Everything was stock.

When I bought it 3 years back, I have spent time and money to restore it back to stock.

I have replace almost everything that I could possibly think of.
- wastegate
- 3rd fuel pump
- spark plug and cable
- 3rd manifold
- double layer radiator
- boost leak test
- ecu check
- air flow sensor check

The boost now, can only reach 0.5 bar and will cough when I exceed 120km.
Should I unplug the air flow sensor, the boost can goes up to 1.0 bar
With air flow sensor, only 0.5bar

Has anyone encounter such issues?
What could possibly goes wrong?
I have visited 5 workshop but none can resolved this.

What's your waste gate spring rate? Make sure it is correct with your desired boost level..

Btw i dont think it's nice to remove the air flow sensor and drive it because that is exactly what is needed by the ecu to calculate how much fuel to dump into your combustion chamber.

Just my 2cents.

 

[kurt_629]

What's your waste gate spring rate? Make sure it is correct with your desired boost level..

Btw i dont think it's nice to remove the air flow sensor and drive it because that is exactly what is needed by the ecu to calculate how much fuel to dump into your combustion chamber.

Just my 2cents.

Hi, I don't know how to identify the spring rate for wastegate but currently, is this a 2nd unit of Tial 38mm wastegate.
Original.

Yes, without the air flow sensor, it is really undriveable.
imagine the engine will stall when coming to traffic light, damn dangerous.
the only good thing is that it can continue to boost..

 

[y2188]

Hi, I don't know how to identify the spring rate for wastegate but currently, is this a 2nd unit of Tial 38mm wastegate.
Original.

Yes, without the air flow sensor, it is really undriveable.
imagine the engine will stall when coming to traffic light, damn dangerous.
the only good thing is that it can continue to boost..

Since you said without air flow sensor can continue boost, i guess its not wastegate problem. Hmm what ecu are you running?

 

[kurt_629]

Since you said without air flow sensor can continue boost, i guess its not wastegate problem. Hmm what ecu are you running?

stock ecu, evo 3. 2364

almost everything is stock..

 

[DanzEterna]

have you checked your coil pack?

 

[y2188]

I think it should be ignition/fuel related issue, check your coil pack like what Danz said..

 

[vr2turbo]

How about the air flow sensor itself?

 

[kymanhalim]

have you checked your coil pack?

thanks for reply man, finally got sifu who use perdana reply.. :)

 

[kurt_629]

have you checked your coil pack?

hey buddy, check.
NSK coil with iridium spark plug.

hows everything, mate.

 

[kurt_629]

How about the air flow sensor itself?

hey hey, checked.
with another air flow sensor, also the same.

with air flow.. 0.5
no air flow, 1.0

 

[kurt_629]

thanks for reply man, finally got sifu who use perdana reply.. :)

yeah, glad to see you guys again.

help me out if you can. I'm still holding strong on this car

 

[lsm1991]

so solved already?? (ayam has ben following since the lyf thread)

 

[kurt_629]

so solved already?? (ayam has ben following since the lyf thread)

nope.. no one knows how and why..

5 mechanic also don't know what happen..
I even try to contact the previous owner but seems like he change his handphone number..
my behasa melayu is damn terrible, can only type in English..

 

[mojo1ne]

What about the o2 sensor? My friends colt had this problem and changed solved.

Sent from my SM-N9208 using Tapatalk

 

[kurt_629]

What about the o2 sensor? My friends colt had this problem and changed solved.

Sent from my SM-N9208 using Tapatalk

does evo 3 actually has a 02 sensor? might be this if true..
how do I know if its faulty? via reading?

 

[mojo1ne]

Yes. Better u use a reader to find the fault. Unfortunately it's not obd2.. Easier.

Sent from my SM-N9208 using Tapatalk

 

[kurt_629]

Yes. Better u use a reader to find the fault. Unfortunately it's not obd2.. Easier.

Sent from my SM-N9208 using Tapatalk

I actually schedule an appointment with a tuner , famous for unichip located in jb - permas jaya.

I was pinning the hope that the reading, would actually tells what is wrong.
But for such an old engine, is it that advance?