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What Would Make An Rb25 Idle Hunt?

copycutter

By copycutter,
in Engines & Forced Induction

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Craved Grand Master

Craved

Posted
Posted
Im not familiar with the plazmaman plenum physically, but before it was bolted up did you put a straight edge over the plenum base where it bolts to the runners to make sure its perfectly flat.

I know on some plenums when they are welded the base warps and if the base isn't machined perfectly flat, it will never seal, even with a gasket.

I doubt this is the issue with such a nice plenum, however some things need be checked when looking for those illusive bugs and gremlins.

I will have a look in the manual for what pin number the TPS wires are a little later tuna_144.

yeah these aren't welded, but they tap studs into them.. but there is a spacer at the bottom of the plenum to raise it like the std one, so not metal on metal.. there is about 3mm

i think ones of these is wrong and not clamping down close enough to the runners flange..

will see how it goes,

carby cleaner does show the leak with the car revving up a little. but is audible when quickly opening the throttle.. bit of hessitation on the road when it does it.

insu Rising Star

insu

Posted
Posted

Put some soapy water in a spray bottle and spray it around the plenum base while the car is running. Open the throttle slightly and look for evidence of air leaking: Ie bubbles.

Plazma man plenum has recieved alot of good feedback. If you used the appropriate gasket, I doubt this would be the source of your problems.

  • 2 weeks later...
plazmaman.com Rookie

plazmaman.com

Posted
Posted

Hi Plazmaman here ,

The whole system was designed as per Nissan factory specs. Nissan factory did not use any sealant on there factory gaskets . We recommend a sealant (threebond) on the gasket - it is a must for high boost applications .

Also check initial gasket thickness , might be a hole in the side .

We will be happy to assist , we have a large team that is willing to help you with any problems relating to our range of products . Any dramas please contact us 02 9725 1728 .

We have never had a problem to date .

Craved Grand Master

Craved

Posted
Posted
Hi Plazmaman here ,

The whole system was designed as per Nissan factory specs. Nissan factory did not use any sealant on there factory gaskets . We recommend a sealant (threebond) on the gasket - it is a must for high boost applications .

Also check initial gasket thickness , might be a hole in the side .

We will be happy to assist , we have a large team that is willing to help you with any problems relating to our range of products . Any dramas please contact us 02 9725 1728 .

We have never had a problem to date .

so a sealant over the factory gasket to assist it to seal. im willing to give it a go.. was thinking this would be the only way around it other than running a shim in there to decrease the gap.

copycutter Experienced

copycutter

Posted
  • Author
Posted

Yeah i'm pretty sure its not a vacuum leak. Will get checked again at Desynz this friday, and getting him to look at the IAC and install my new speedo sensor.

Excellent plenums you guys make btw, am very happy with it. Its always the first thing people notice and ask about when i pop the hood :cheers:

What do you recommend to keep the mirror finish though? I tried some of that Autosol metal polish and it helped a bit, just after some suggestions, and I guess the person who made it would be best to ask.

Cheers

plazmaman.com Rookie

plazmaman.com

Posted
Posted

Polish plenum using MOTHERS mag and aluminium polish . Small circles using a quality polishing cloth we found is the best way . Other polishes are scratchy and dull up after a while .

Our instruction leaflet with the plenum stated to use sealant . If you havent ,that is definately the problem .

Also idle speed motor do get clogged with soot and carbon - maybe clean and blow with air hose .

We have had news today that a customer has made 695 Rear wheel hp with one of our plenum / swept back kits on their car . We will hear more shortly . We are proud that our products make big reliable horsepower .

osiris23 Rising Star

osiris23

Posted
Posted

i was having idle problems so i went and saw my mechanic friend. He told me to get this stuff from the Subaru Dealer which is a Upper Engine Cleaner. You spray it into a vaccum line in the plenium then do what it says. it clears out all the carbon build up and junk. I also added in some Nulon Trade Strength injector Cleaner. Useing the both of these my car runs much much better while driving and goes seems to have heaps more power and the idle does not hunt any more. The stalling side of it he rekons is the idle control sensor which apparently with shit fuel we have around here chokes it up. How true is all this? Must have some trueness to it as my car is running heaps better since i didd this at the cost of all about $25.

Craved Grand Master

Craved

Posted
Posted
Polish plenum using MOTHERS mag and aluminium polish . Small circles using a quality polishing cloth we found is the best way . Other polishes are scratchy and dull up after a while .

Our instruction leaflet with the plenum stated to use sealant . If you havent ,that is definately the problem .

Also idle speed motor do get clogged with soot and carbon - maybe clean and blow with air hose .

We have had news today that a customer has made 695 Rear wheel hp with one of our plenum / swept back kits on their car . We will hear more shortly . We are proud that our products make big reliable horsepower .

Alex,

have you tested these plenums on the R34 GTT runners? do they fit?

think i put the instructions down after having to drill out the std bolt locations on the lower section to be able to fit the studs through .. oh well

will try the sealant on the gasket and see if she gets fixed up :)

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