Jump to content
SAU Community

Strange Problem With My R32

noakespg

By noakespg,
in Engines & Forced Induction

 Share

Recommended Posts

noakespg Collaborator

noakespg

Posted
Posted

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

Link to comment
https://www.sau.com.au/forums/topic/108024-strange-problem-with-my-r32/
Share on other sites
nemz Experienced

nemz

Posted
Posted

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 :P 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 :iluvff:

TTT Grand Master

TTT

Posted
Posted (edited)

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 by GTST
DRFTWU Apprentice

DRFTWU

Posted
Posted

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 Proficient

buggor34

Posted
Posted

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 Contributor

rory_kieran

Posted
Posted

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 Collaborator

noakespg

Posted
  • Author
Posted (edited)
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 by noakespg
TTT Grand Master

TTT

Posted
Posted

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 Proficient

ellie

Posted
Posted

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 Collaborator

ODessA

Posted
Posted (edited)

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 by ODessA
J_R32 Experienced

J_R32

Posted
Posted

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?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Milkmun
      The FD RX7 is the best looking 90's JDM car

      By Milkmun · Posted

      Lucky man, who owns it in the family? Any pics? 
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      The engine stuff is Greg Autism to the Max. I contacted Tony Mamo previously from AFR who went off to make his own company to further refine AFR heads. He is a wizard in US LS world. Pretty much the best person on earth who will sell you things he's done weird wizard magic to. The cam spec is not too different. I have a 232/234 .600/603 lift, 114LSA cam currently. The new one is 227/233 .638 .634. The 1.8 ratio roller rockers will effectively push this cam into the ~.670 range. These also get Mamo'ified to be drilled out and tapped to use a 10mm bolt over an 8mm for better stability. This is what lead to the cam being specced. The plan is to run it to 6800. (6600 currently). The Johnson lifters are to maintain proper lift at heavy use which is something the LS7's supposedly fail at and lose a bit of pressure, robbing you of lift at higher RPM. Hollow stem valves for better, well everything, Valve train control. I dunno. Hollow is better. The valves are also not on a standard valve angle. Compression ratio is going from 10.6 to 11.3. The cam is smaller, but also not really... The cam was specced when I generated a chart where I counted the frames of a lap video I had and noted how much of the time in % I spent at what RPM while on track at Sandown. The current cam/heads are a bit mismatched, the standard LS1 heads are the restriction to power, which is why everyone CNC's them to get a pretty solid improvement. Most of the difference between LS1->LS2->LS3 is really just better stock heads. The current cam is falling over about 600rpm earlier than it 'should' given the rest of my current setup. CNC'ing heads closes the gap with regards to heads. Aftermarket heads eliminate the gap and go further. The MMS heads go even further than that, and the heads I have in the box could quite easily be bolted to a 7.0 427ci or 454 and not be any restriction at all. Tony Mamo previously worked with AFR, designed new heads from scratch then eventually founded his own business. There he takes the AFR items and performs further wizardry, CNC'ing them and then manually porting the result. He also ports the FAST102 composite manifold: Before and after There's also an improved racing crank scraper and windage tray. Helps to keep oil in the pan. Supposedly gains 2% power. Tony also ports Melling oil pumps, so you get more oil pressure down low at idle, and the same as what you want up top thanks to a suitable relief spring. There's also the timing chain kit with a Torrington bearing to make sure the cam doesn't have any thrust. Yes I'll post a before and after when it all eventually goes together. It'll probably make 2kw more than a setup that would be $15,000 cheaper :p
    • MBS206
      Can't put strut back

      By MBS206 · Posted

      Because the cars wheels are on blocks, you slide under the car.   Pretty much all the bolts you touched should have been put in, but not fully torque up.   Back them off a turn or two, and then tighten them up from under the car with the wheels sitting on the blocks holding car up in the air.
    • MBS206
      Can't put strut back

      By MBS206 · Posted

      Yes. Imagine you have the car on the ground, and you mine away all the ground under and around it, except for the area directly under each individual wheel. That's exactly how it'd look, except the ground will be what ever you make the bit under each wheel from
    • GTSBoy
      Can't put strut back

      By GTSBoy · Posted

      Yes, if you set the "height" right so that it's basically where it would be when sitting on the wheel. It's actually exactly how I tighten bolts that need to be done that way. However....urethane bushes do NOT need to be done that way. The bush slides on both the inner and outer. It's only rubber bushes that are bonded to the outer that need to be clamped to the crush tube in the "home" position. And my car is so full of sphericals now that I have very few that I need to do properly and I sometimes forget and have to go back and fix it afterwards!
×
×
  • Create New...