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Cas Problems And Possible Solutions...

kdwebber

By kdwebber,
in Engines & Forced Induction

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kdwebber Apprentice

kdwebber

Posted
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Hey guys first off just like to say that this is an awesome website. I'm more of a lurker/reader but i still find this site very helpfull. There are not many rb25's in Canada which makes this site even more useful.

Anyways I've been having problems with my series 1 rb25det for quite a while now. When the car warms up to about 83-85 celcius the car begins to hesitate and shudder. It almost feels like the car is not getting enough fuel. The car wont stall but it will not move forward either. Eventually the car becomes undriveable and I am forced to limp home pulling over, waiting, and then continuing on my way. After changing couplers, seals, amf's, plugs, fuel filters, cleaning and testing coils among other things I finally changed out my cas and the car ran noticeably better but still far from perfect. Presenly the car runs ok up to about 4500-5000 rpm where there is a noticeable lack of power and the car will not rev any higher. Even after changing the new cas the same problems have come back when the weather outside reaches 25 degrees celcius.

Upon closer inspection the half moon (the part that attatches to the cam) appears to be slightly damaged. I've read that this can cause the timing to be off among other things.

My questions are has anyone else experienced this problem?

Does anyone know what would caues the apparent damage to the half moon?

It appears that the half moon that attatches to the cam can be removed and replaced. Can I order this part from nissan?

Any help or advice would be greatly appreciated.

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kdwebber Apprentice

kdwebber

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fuel pump rooted??

I suspected the fuel pump but the car will run horribly, I will shut off the engine for 10-20 seconds, restart the car and it will hit full boost again until the problem re appears somewhere in the next 2-10 mins.

kdwebber Apprentice

kdwebber

Posted
  • Author
Posted (edited)
fuel pump.

A new fuel pump is definetly a good idea. Not sure if the fuel pump was upgraded when the swap was done, might still have the old r32 pump in there.

Eventhough the fuel pump does need an upgrade sooner than later im almost confident the problem lies with the cas. just curious if anyone has had a similar problem or knows why the damage has occured to the half moon.

Edited by kdwebber
SECURITY Grand Master

SECURITY

Posted
Posted

yeah. what you'll notice if the cas is shagged that it'll be like that constantly as well as have a fair bit of black smoke come out the exhaust (as the fuel wont be firing).

if you feel like you're getting a fair bit of hesitation and it is completely random (not misfire) then its most likely your fuel pump.

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