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Hi out there, does anyone know what an rb 26 is meant to idle at standard, i have an arc air box and cat back exhaust.

it idles around 1050-1100

from past experience all my cars being manual have sat around 800 or so.

does anyone know how to adjust the idle on an rb26?

do you adjust the throttle bodie linkage near the accelerator cable or something else?

any info would be much appreciated.

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Hi out there, does anyone know what an rb 26 is meant to idle at standard, i have an arc air box and cat back exhaust.

it idles around 1050-1100

from past experience all my cars being manual have sat around 800 or so.

does anyone know how to adjust the idle on an rb26?

do you adjust the throttle bodie linkage near the accelerator cable or something else?

any info would be much appreciated.

Hi mate! On the RB26 you have three methods of adjusting ur idle speed: ECU (aftermarket), throttle linkage and AAC Valve. The main place to adjust ur idle would be on the AAC valve located under ur intake plenum. This is an adjustable screw, mid section under side of plenum facing forward. If you screw this screw clockwise, ur idle speed will decrease, anti clock wise and ur idle speed will increase. I personally would not adjust ur throttle linkage, leave it be! RB26's are happy to idle around 650 - 800 RPM. I have a Nissan service information sticker under 33 vspec bonnet and it stipulates idle RPM to be 650. Hope this helps u out!

Hi mate! On the RB26 you have three methods of adjusting ur idle speed: ECU (aftermarket), throttle linkage and AAC Valve. The main place to adjust ur idle would be on the AAC valve located under ur intake plenum. This is an adjustable screw, mid section under side of plenum facing forward. If you screw this screw clockwise, ur idle speed will decrease, anti clock wise and ur idle speed will increase. I personally would not adjust ur throttle linkage, leave it be! RB26's are happy to idle around 650 - 800 RPM. I have a Nissan service information sticker under 33 vspec bonnet and it stipulates idle RPM to be 650. Hope this helps u out!

yup, that is by far the best and easiest way to ajust the idle

when your ajusting it, start the engine, get a long screwdriver, turn the screw, after each ajustments wait about 10~15 senconds for the idle speed to settle

yup, that is by far the best and easiest way to ajust the idle

when your ajusting it, start the engine, get a long screwdriver, turn the screw, after each ajustments wait about 10~15 senconds for the idle speed to settle

thanks heaps guys eally appreciate your info. :)

  • 7 years later...

a very common cause of high idle for the rb26 is some plonka has cleaned inside the throttle bodies.

they have a factory film, clean that off and you get a 1100-1200 idle. it wont be helped by the idle screw either so crack the plenum off and check that also.

6 hours ago, powerdbygarrett said:

Hate to bring up an old thread but can someone confirm the location of the screw? 

Is it one of these guys? 

Thanks!

unnamed (1).jpg

Wow a car that still has HICAS!

Anyway, that is the AAC and the idle screw is on that. It may be the screw in your red circle (hard to tell in that pic). Depending on how standard your car is, the ECU also has an idle adjust screw and the throttles themselves could be adjusted.

If you have developed a high idle, its more likely you have an air leak somewhere in the intake. AAC should never really need adjustment unless you've just given it a full clean out internally

On 11/6/2016 at 11:20 PM, GH05T said:

a very common cause of high idle for the rb26 is some plonka has cleaned inside the throttle bodies.

they have a factory film, clean that off and you get a 1100-1200 idle. it wont be helped by the idle screw either so crack the plenum off and check that also.

This is the way I purchased the car. I am not sure how the idle was with the previous owner. If the film has been cleaned off, what would be the solutution?

On 11/7/2016 at 1:56 AM, Duncan said:

Wow a car that still has HICAS!

Anyway, that is the AAC and the idle screw is on that. It may be the screw in your red circle (hard to tell in that pic). Depending on how standard your car is, the ECU also has an idle adjust screw and the throttles themselves could be adjusted.

If you have developed a high idle, its more likely you have an air leak somewhere in the intake. AAC should never really need adjustment unless you've just given it a full clean out internally

The car seems pretty standard, not really modded. just basic stuff. I will check for vacuum leaks. 

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