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VCT Rattle, solutions?

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Pheonix

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MY S15 has developed the dredded VCT Rattle, was only quiet a few weeks ago, it's starting to get unbearable when poking my head in the engine bay when I just start it, normally taked 10-15 mins at idle to go away.. or 5 mins driving.. So I was woundering what I should do or what it could be. I've established it's either the Gear or the Solernoid, either way, should I replace the VCT Gear Sprocket for a new one, or just put an adjustable sprocket in?

Cheers.
 
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It's up to you what you replace it with. The VCT gear is the easiest option, if you go with cam gears you will need to have the car retuned.
 
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Apples for apples,it will cost you about the same for gears installed and tuned and you will sacrifice the VCT as well.
 
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odd... you say 10 to 15 min at idle, but that's with a gear in and clutch pressed? VCT is only active when the transmission is in any gear position, and is off when on neutral if i recall correctly.
 
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VCT is, or more correctly NVCS (Nissan's terminology) governed by engine RPM, not gearbox engagement. The issue with it is the gear engagement unit has a very small oil lubrication hole and with time and oil deposits blocks up and causes it to fail. Solenoid failure is also the other issue but is not as prevelant as the NVCS gear.

Installing bigger cams or stiffer valuve springs can exacerbate the failure
 
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i thought i saw in the FSM that the ECU takes five different signals to turn on intake valve timing solenoid, these are maf, vss, coolant temp, throttle position and gear position, mine does not engage when on neutral (you can check by hearing the clicking sound of the solenoid).
 
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I'm in the same situation, except my vct makes an embarassing loud rattling noise after a bit of driving around, and only when on idle or very low rev (1500-2000ish)... I think it's well time to replace it?
 
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i just changed it last year. VCT + soleniod. If u are changing vct, might as well change the solenoid. The solenoid is alot cheaper. But after 1 year, it seemed to have developed again the rattle (occasionally)... I think better change to cam gear. yes i do have BC springs and 256 cams. Straight after installation i got them, that was when i changed the vct and solenoid.
 
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Pheonix

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I feel like an idiot...

All fixed now, it seemed that the last person to put oil in it, forgot to put oil in.. and it's been running on half a cup of oil.. Now it's been filled the pressure is up and the rattle is gone (except for startups), since there's finally oil getting to it! which is a releif.. And it's my fauly for not properly checking the oil >.> Apologies for this thread.
 
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