Boost Problem R34 Gtr

[Turbo Piston]

Hey guys,

I just got my R34 serviced, replaced the coils, adjusted the idle a little bit and replaced the boost sensor.

Now i realised when i gave it a bit, boost did not go over .86 bar at all. Why is that? Normally it will go to around 1bar of boost!!

I'm stressed and worried!

It would have to be the boost sensor right? Does it need a reset or something?

Thanks!

[Johnny]

That seems to the be the stock boost level of an r34, wouldnt be too worried. and it gives you some security against boost spiking in 1st and 2nd gear.

Try it yourself, nail the throttle in 2nd and see what boost you reach on the mfd.

then nail in 3rd gear and see what the boost reaches

ps: dont forget to reset the mfd (middle joystick) everytime.

you have an EBC??? computer???

[Duncan1]

Hey guys,

I just got my R34 serviced, replaced the coils, adjusted the idle a little bit and replaced the boost sensor.

Now i realised when i gave it a bit, boost did not go over .86 bar at all. Why is that? Normally it will go to around 1bar of boost!!

I'm stressed and worried!

It would have to be the boost sensor right? Does it need a reset or something?

Thanks!

I know what your experiencing, mine does this to on occasion. More often than not mine will run up to 1.07 on the mfd, then every now and then something happens and it runs a max of about 0.8 bar and feels very flat and lathargic. I have no idea why, and its an intermittant fault, generally when its warm and it has been driving in a spirited fashion. I can turn the car off and start it again and it goes away!!! cant work it out...I was hoping it was just a minor fault [glitch]with the factory ecu, so i figured once i had a pfc it would be problem solved!!!! That may or may not fix the problem though.......

Im very interested if somebody can solve this problem for us, if indeed we have the same problem....

Paulr33 please help mate!!!! cheers!!!

Edited September 28, 2008 by Duncan1

[Johnny]

I know what your experiencing, mine does this to on occasion. More often than not mine will run up to 1.07 on the mfd, then every now and then something happens and it runs a max of about 0.8 bar and feels very flat and lathargic. I have no idea why, and its an intermittant fault, generally when its warm and it has been driving in a spirited fashion. I can turn the car off and start it again and it goes away!!! cant work it out...I was hoping it was just a minor fault [glitch]with the factory ecu, so i figured once i had a pfc it would be problem solved!!!! That may or may not fix the problem though.......

Im very interested if somebody can solve this problem for us, if indeed we have the same problem....

Paulr33 please help mate!!!! cheers!!!

Hey duncan, remember i had the same prob as you? well mines all fixed now after i installed my new EBC. I got the HKS EVC version 6.

it hold boost nicely at 1.0bar in 3rd gear loads but in 2nd there is no stopping the boost spike to 1.10-1.20bar. Im contemplating buying the HKS actuators which are preset to 0.8-1.1bar and see if that helps.

Oh a little problem found was a loose vacumn line under the plenum chamber which was throwing off proper boost control so you might wanna get someone to check it out.

Took my tuner 2 hours to diagnose the prob; we thought it was the ebc faulty.

[DrewII]

check all of your hoses and when i say all of them i mean absolutely everyone so no cracks or holes are present at all.

[Turbo Piston]

I will run over the hoses, but I am pretty sure they are fine.

Before I could drive the car and hit 1.02 Bar of boost no problem, but yesterday after i got it serviced it just stopped at .86 Bar. Bit dissapointing because you don't feel the power come on.

So you think you can turn the car off and it will go away? You will reach 1.0 bar of boost then? I will give that a go too, see if that works. Just annoying!

If someone gets a new ECU or boost controller, let me know if that helps.

[R33GOD]

reset your ecu

[Duncan1]

Hey duncan, remember i had the same prob as you? well mines all fixed now after i installed my new EBC. I got the HKS EVC version 6.

it hold boost nicely at 1.0bar in 3rd gear loads but in 2nd there is no stopping the boost spike to 1.10-1.20bar. Im contemplating buying the HKS actuators which are preset to 0.8-1.1bar and see if that helps.

Oh a little problem found was a loose vacumn line under the plenum chamber which was throwing off proper boost control so you might wanna get someone to check it out.

Took my tuner 2 hours to diagnose the prob; we thought it was the ebc faulty.

Thanks again mate, will get it sorted soon, ebc sounds like a good idea. Bit scary when you see 1.2 bar register on the mfd!!! feels great though!!!!

Sorry for gatecrashing your thread Turbo Piston.....

Edited September 28, 2008 by Duncan1

[Bakes]

I have same boost controller as Johnny. I run 1.2 bar every day on stock turbos. No dramas.

If I go on a mountain run where I will be on and off boost continuously for a long period, I just adjust it back to 1 bar.

Turbo Piston, I would suggest pitting an EBC in for sure

[Turbo Piston]

Alright, I'm going to check all hoses and reset the ECU first.

How do I reset the ECU? I'm assuming there is a reset button on it?

And another way to fix it would be to get a boost controller?

Before all this though guys, what was your R34 GTR displaying on the MFD? did it vary as well? Or normally sit on the 1.0 bar of boost?

[Bakes]

Before I put the boost controller in it varied a bit, never used to go past ~0.90 on the MFD.

The MFD doesnt actually display bar either, its kg/cm squared which is close to bar but not exactly the same.

[Turbo Piston]

Looks like everyone's reading is different. I finally took my car out for a drive since i wrote this post, been sick in bed. Assuming all the hoses were good, I gave it a go.

Soon as I turned it on, I realised the MFD was displaying the oil temp I had 4 days ago, which is a bit odd, normally it displays - - since there is no recording yet.

Anyway got to the servo, turned the car off, turned it back on and the oil was back to normal -- good. Think the car needed a reset, don't know!

First gear .96

Second 1.02

Third (not enough road)

Did that several times, pretty much identical recordings, so maybe after the service it just needed to be switched off or something. Unless when its hot outside and it has been driven hard, it automatically reduces the amount of boost. Because during the service of the car, it was a really hot day and the car had been on for while and a bit of hard driving was used too.

[Bakes]

Yeah it wil boost up more in cold weather definately