Strange Problem With My R32

[noakespg]

Hey everyone,

I have recently had a FMIC installed on my R32 GTS-t. The car seems to go heaps better but on cold mornings when I try and give it some boot it seems to boost up well but then at about 4000rpm the factory BOV will sound and I will loose all throttle and revs will drop. I shift down and the car is back to normal. This may happen twice in a row but then it seems to go away as the car warms up.

It almost feels like an intercooler pipe has blown off but the car doesnt stall and the problem goes away.

I have tried to search but I have no idea what the problem is. The car is running between 12 and 14 psi on a bleed type boost controller and may be overboosting but I cant tell without a boost gauge.

Thanks

[nemz]

well a stock plumback should be changed if you boost your car any more then stock. i had problems with it back when my car was pretty stock with only an exhaust and pod on 11 psi, would fuel cut and do all sorts of stupid things, oh and was also because stock fuel pumps are shit to so i advise, change you blow off, get an aftermarket plumback or vented blow off, and also a bigger fuel pump, also a boost guage is very cheap and easy to install, if your in west syd, id install either a blow off or boost guage if you dont know how to when i have free time

[dbo]

I have a GFB plumback blow off valve off an R32 for sale.. bolt's into place of the stock BOV.. PM me if ytour interested..

Definately upgrade your fuel pump.. your BOV shouldn't be opening at 4000 rpm..

[TTT]

NEMZ - wow... that has to be the most misguided reply yet.

noakespg - give more information.

1.) is the car at normal operating temps when it does this or when it still shows cold on the factory temp gauge. after how many minutes of driving does it stop doing this?

2.) have you checked all the intercooler piping and clamps?

3.) have you checked the vacuum line to the bov, to the bleed valve, and the plumback hose of the bov?

from my experience.

rb20's seem to have this wierd CHOKE funciton when cold.

when my car is cold, it is JERKY so to speak untill about 5 minutes of regular (no boost, nothing over 3000rpm) driving. then the choke goes off.

the best way I can describe the feeling is that it's like the car is being held back then quickly released (to describe the jerkyness).

once it is warm, this doesn't happen.

I ask you to check the pipes and clamps cause you said it happens at 4000rpm (ish)... this is when the turbo has hit full boost and all the pipes and intercooler are all fully pressurised.. this may be causing a lose clamp to allow some air to escape.. and it doesn't do it as when it heats up the pipe may be expanding a little to keep it from escaping.. (just a long shot here)

I also say the vacuum line to the bov and hose for plumb back. if the vacuum line has a split, it will bleed air and the bov will open early as it doesn't have any pressure above the piston and when you come on boost, it will just be forced open.

how do you know how much boost you car is set to if you don't have a boost gauge?

what does the factory boost gauge read when you have your foot burried?

give some more info and there may be more to help you.

Edited March 3, 2006 by GTST

[DRFTWU]

i had the same problem on my ca...get to about 4ooorpm then it would just stay there and not go up i took out the stock fuel pump and replaced it with a bosch 070 and problem solved...might not be the same problem but may be the case...

[buggor34]

It could be a boost cut. Put a temporary guage on one of your vacuum lines & see how much boost the car is running. The higher the gear your in (car is under more load) the more boost it will run. Bleed valves can be very fluctuating & in accurate. Try taking the bleed valve off & see if this fixes the problem.

Its never a good idea to have a boost controller installed with no boost guage to monitor it. Also the standard bovs are actually better than most aftermarket ones, in most cases they can hold up to 20psi. Yours maybe just busted!

[rory_kieran]

I don't think you really need to look to much into this. My R32 is the exact same however I just warm the car up for a few minutes before I drive (or drive it very slowly). This stops the problem, just as GTST said. About the fuel pump, you can pick up a Walbro fuel pump real cheap which do a great job. If you want one just PM me.

You should really also get a boost gauge. They are cheap from autobarn and are good for getting accurate readings.

[noakespg]

1.) is the car at normal operating temps when it does this or when it still shows cold on the factory temp gauge. after how many minutes of driving does it stop doing this?

The car is between 0% and 25% of normal operation temps.

5 minutes and the problem seems to be gone.

2.) have you checked all the intercooler piping and clamps?

It is definately NOT the intercooler. All hoses and clamps are good. The car does not stall so the pipes are still there. This was the first thing i checked.

3.) have you checked the vacuum line to the bov, to the bleed valve, and the plumback hose of the bov?

Not yet but i will now

how do you know how much boost you car is set to if you don't have a boost gauge?

We had a boost gauge hooked up to the car when we were tuning it. It was around 12psi.

what does the factory boost gauge read when you have your foot burried?

It usually goes a little past 7. My instrument cluster does need replacing however because the speedo, oil, and tacho are all slightly off.

Oh I forgot to mention that my car is already running a GTR fuel pump.

Thanks for the quick replies guys!

Edited March 3, 2006 by noakespg

[TTT]

a little past 7 on the stock gauge is somewhere near 14psi mate..

A vdo boost gauge will set you back about $40 and are very accurate.

cheap insurance if you ask me.

if it only does it when cold, don't worry about it.

like I said, drive sedately it till it is at half temp, then about 2 minutes after that it is good to go.

I'm surprised you thrash it when it is stone cold.

that like getting out of bed putting some shoes on and lining up for a 100m sprint in the olympics..

meaning it's gonna break/pull/strain something.

[ellie]

My guess: a Boost cut of sorts. What Gtstis desribing is when the car is cold the computer enrichens the mixture to keep the car running right. On the other hand in japan with their emissions the idle and just off are very lean which is why commonly when you get you car tuned with S-AFC,PFC etc the tuner will actually richen up this part of your fuel map. So when your car is cold it will feel jerky due to the computer trying to keep the mixture as lean as possible then when atmospheric preesure or above is detected the computer heavily enrichens the mixture for positive boost and an instant power hit. Feeling as though holding a horse back by a rope and then suddenly leeting go sensation!

On to your current problem: I would perhaps suggest the your tettering right on the edge of the computers calculations so when the motor is cold and in a heavily richened state while hitting boost the computer thinks that too much fuel is bieng added so simultaniously there must be to much air folw so it cuts out. But once the motor warms up it's happy with the amount of fuel/air consumption hence no cut out

Something to ponder over any way

[ODessA]

gtst i know what u mean about the rb20 feeling wierd when driving it cold like it holds back then lets go i always thought it was more to do with just driving the thing with a cold transmission and that the 32 choke would run it rich and u would get a strange kick off that.

and +7 on the stock boost gauge is atleast 14psi.

ur crazy to up the boost without a gauge, and even crazier to boost the car before its at operating temp

Edited March 5, 2006 by ODessA

[J_R32]

Hi, apologies to hijack this thread but i feel it is related. i understand that all Rb20dets have this "cold-choke" function, but my issue when my car is cold is that as soon as it starts getting some positive pressure(even 1psi on my aftermarket gauge) i will immediately hear a sort of "flapping-ticking" sound. this sound will disappear once the car is running normal operating temp. it should also be noted that it boost wont climb very fast, compared to when it is running at normal tempurature but i believe that is because of the "cold-choke" function, computer running some retarded timing on the engine.

anyone else have this sound when cold, or know what it could be?