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RB25 Fuel and compressor surge issues.

Redknight

By Redknight,
in Engines & Forced Induction

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Redknight Explorer

Redknight

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Posted (edited)

RB25 Fuel and compressor surge issues.

HI guys

I just want to say how frustrated I am with my stupid car. I have sent this issue to 4 mechanics in gold coast and no one can seem to fix it.

Basically the car feels like its compressor surging under light acceleration and feels like something is restricting the car power wise. The car wont pull like it should and feels more like a civic. The car also sounds raspier and harsher than it usually does.

The back of my bumper is caked with oil and completely black. Looks like it might be over fueling or something. You would think it would be picked up on the dyno though.

 At times, although rare, it will free itself up and boost like it should but its a rare occurrence when this happens.

when this is happening the car is is using a crap load of fuel. It would easily go through a whole tank of fuel in half a day. This isnt normal.

I think lowering the boost and duty on the EBC seems to help slightly but im not sure. 

I have had the car on the dyno and no one can seem to find the issue.

mods I have done

Power FC

front mount 

full exhaust

spit fire coil pack

aftermarket fuel pump

AVCR boost controller

stock turbo and injectors. 

I have done everything humanly possible to fix it. Boost leak test, replace waste gate actuator. All new piping. I don't know what else to do!

any help would be greatly appreciated.

 

 

Edited by Redknight
KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

None of your mods are really going to make your car get up and go but since you have a PFC it should be tuned by someone who is familiar with RBs.

This one is not very close but does come highly recommended: http://dvstuning.com.au/contact/

Maybe members can find you someone adequate closer to you.

Redknight Explorer

Redknight

Posted
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2 minutes ago, KiwiRS4T said:

None of your mods are really going to make your car get up and go but since you have a PFC it should be tuned by someone who is familiar with RBs.

This one is not very close but does come highly recommended: http://dvstuning.com.au/contact/

Maybe members can find you someone adequate closer to you.

 

Thanks for the reply mate. My car was tuned by PITTS at Molendinor. 

it made over 200kw at the wheels so its not too bad. Problem is the surging under acceleration is making the car lose power.

do you think it could be tune issue? I hope not because PITTS is considered the best in Australia according to many people.

Redknight Explorer

Redknight

Posted
  • Author
Posted
2 minutes ago, hy_rpm said:

Turbo intake been replaced?
Known to suck shut under more boost power and heat

Hey mate. No its still using the stock turbo intake. It does feel pretty soft though.

I am running 13 pound boost. Would it suck shut with that amount of boost? And would it be picked up on the dyno?

 

Redknight Explorer

Redknight

Posted
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Posted
15 minutes ago, hy_rpm said:

Yes depending on the condition and age
Depends on the dyno as the bonnets open and only do afew full power runs for short burst
Where as on the road under bonnet temps are alot higher and running under load alot longer

Thanks a lot for your help. I will replace it with a metal intake and see if it helps.

would the intake sucking shut make the car compressor surge under acceleration? 

AngryRB Grand Master

AngryRB

Posted
Posted (edited)

One thing to double check is the fuel lines, i'm not sure on the details but i have seen on a previous car when the lines got confused, the vapor line was hooked up to the return and the return on the vapor nipple...  the two nipples were different size internally and the car sucked up raw fuel under vacumn and pumped out a shitload of fuel on load.

Also, try Gavin Woods at Autotech, he knows RB's.

Edited by AngryRB
Redknight Explorer

Redknight

Posted
  • Author
Posted
28 minutes ago, AngryRB said:

One thing to double check is the fuel lines, i'm not sure on the details but i have seen on a previous car when the lines got confused, the vapor line was hooked up to the return and the return on the vapor nipple...  the two nipples were different size internally and the car sucked up raw fuel under vacumn and pumped out a shitload of fuel on load.

Also, try Gavin Woods at Autotech, he knows RB's.

 

Thanks a lot guys. You might be on to something there mate as my vapor lines don't look right. Ill be taking my car to Gavin wood on monday.

 

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