GTR boost problems....

[jlnewton]

I have been noticing of late my car (33 GTR) has been feeling quite sluggish. Put it down to getting too used to it and my clutch is a little average atm. But under closer inspection I have been noticing that most of the time now my car isn't coming on to boost as it should. My car is stock except for a HKS dual dragger exhaust, including front pipes. Everything else is untouched. When the car feels strong the stock boost guage goes up to a couple of mm under the +7 mark but when the car feels sluggish the highest it gets to is the half way graduation mark which would be +3.5 I suppose. Sometimes its good and other times it feels sluggish.

Any ideas as to what is causing this inconsistant boost problem? I am thinking a boost leak somewhere atm, although I can't really hear anything. Could this problem be caused by a dodgy actuator or wastegate? or maybe something more serious. The car otherwise is running perfectly.

Thanks in advance....

[Tommyk]

I have the same issues

It only happens occasionally. I found that turning the car off and then back on fixes the problem. Mind you this has only happened to me twice where ive noticed boost problems. Personally Im thinking it may either be a problem with the computer or the boost solenoid.

Let me know if you find out what it is. My car is completely stock (even exhaust), so I dont know where the problem could be. Like you, i hope its not a more serious problem

[NIS.26L]

I have the same issues

 

It only happens occasionally. I found that turning the car off and then back on fixes the problem. Mind you this has only happened to me twice where ive noticed boost problems. Personally Im thinking it may either be a problem with the computer or the boost solenoid.

 

Let me know if you find out what it is. My car is completely stock (even exhaust), so I dont know where the problem could be. Like you, i hope its not a more serious problem

mine does it only when you hit the speed limter (185kph) i have been told it go's in to limp mode and when you turn the car off it resets its self i now have a power fc computer and it dosent happen any more

[gtr fan]

Your problems sound very similar to one i had about 18 months ago when I first got my 32 gtr. Soemtimes the car would only get 50% boost but then swithching the car off for a couple of minutes seemed to fix this but it was very annoying as it happened frequently. I tried a new blitz boost controller hoping that it was just the boost solenoid but the problem remained, then i put in a power FC and the problem went away. Try putting in another ECU and see how you go.

[Tommyk]

Sounds ECU related then.

Im not fussed about mine because it doesnt happen very often. And if it does, I'll just turn my car off and then back on

[jlnewton]

hmmmmm. Mine is happening quite frequently, and just occurs during normal driving. I just go to give it a little squirt every now and then and it does doesn't feel like it wants to go. Check the boost guage and sure enough its only half way. Might be a good excuse to get a powerfc then huh . Next time it happens I will turn it off and restart to see if it has any effect.

Cheers

[wrxhoon]

I have been noticing of late my car (33 GTR) has been feeling quite sluggish.  Put it down to getting too used to it and my clutch is a little average atm.  But under closer inspection I have been noticing that most of the time now my car isn't coming on to boost as it should.  My car is stock except for a HKS dual dragger exhaust, including front pipes.  Everything else is untouched.  When the car feels strong the stock boost guage goes up to a couple of mm under the +7 mark but when the car feels sluggish the highest it gets to is the half way graduation mark which would be +3.5 I suppose.  Sometimes its good and other times it feels sluggish.

Any ideas as to what is causing this inconsistant boost problem?  I am thinking a boost leak somewhere atm, although I can't really hear anything.  Could this problem be caused by a dodgy actuator or wastegate? or maybe something more serious.  The car otherwise is running perfectly.  

Thanks in advance....

Your problem is the ecu knocks the boost down because its knocking or leaning out up high in the rpm to prevent engine damage .You will find it will reset itself when you turn it off but will do it again especialy if you dont have the restrictor in and you get crapy fuel .

As gtr fan stated a power f/c will fix it , in the meantime be carefull your engine may go boom .

If your car was stock it wouldn't happen but the exhaust and maybe the removal of the restrictor will give you more boost . Your stock ecu is not programed for that .

[Tommyk]

ive got boost restrictor removed.

But I thought that the GTR ran rich anyway. I have stock exhaust.

You could be right about that. its probably knocking, and then going to limp mode. Always run on 98 ron petrols

Anyone know what the boost level is for limp mode ?

[jlnewton]

Interesting, I always run 98 fuel, usually BP ultimate, and haven't touched the boost restrictor although I am prolly running a little higher than stock boost due to the exhaust. Have done a couple of power runs on the dyno before and after the fitment of the exhaust and it ran quite rich up high, 10s and 11:1 if I remember correctly. But I did notice down low in the revs in ran leanish then on boost it richened up quite a lot. If all goes well I will get a chance today to try restarting it. Hope that is it....

[wrxhoon]

ive got boost restrictor removed.

 

But I thought that the GTR ran rich anyway. I have stock exhaust.

You could be right about that. its probably knocking, and then going to limp mode. Always run on 98 ron petrols

Anyone know what the boost level is for limp mode ?

With stock ecu it will run rich low to mid rpm but will lean out at high rpm .

Put your restrictor back and will fix the problem . 98 ron fuel is not always the same , if its a bit old for instance .

Boost level will drop to around 6-7 psi when the boost solinoid is not working .

Thats the pressure actuators will open .

[jlnewton]

That is exactly what it is dropping to, the same as the stock reading for the GTST. One bonous is it does get quite good fuel economy at that boost level.