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VCT Problem

Dev RB25

By Dev RB25,
in R Series (R30, R31, R32, R33, R34)

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Dev RB25 Explorer

Dev RB25

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VCT Problem

Hi guys,

 

I have an issue with power loss at 5.5k rpm onwards, after much troubleshooting im quite certain fault lies at the vct.

I disconnected the plug, went for a drive and no changes. Same power at low end...and same power loss at high. I removed solenoid to see if actuator is working and it is. ticks and closes when fed direct 12v.

Power fc is sending the signal. So its not the ecu.

Now when i put the solenoid back into the head. wired direct 12v into it... it ticks and can feel the actuator moving(vibrates)  however no change in idle whatsoever. From what i understand there was suppose to be a noticeable change in idle when the actuator closes. nothing happens.

Would this point to the vct cam pulley mechanism being stuck/jammed?

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admS15 Grand Master

admS15

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If it is the vct, it would be stuck in the on position. That would explain the power loss after 5.5k, that's around the switch off point. I'm not really sure how you can trouble shoot it. I have seen second hand vct gears for sale on eBay for cheap as if it comes to that. Good luck.

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Dev RB25 Explorer

Dev RB25

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yea mate, im somewhat confident its the issue, but before i go ahead and replace the cam gear, just wanna know if there was anyway i can confirm its stuck inside or something. so that at least ill understand what happened. or what caused it and such. im worried that i replace it and problem lies elsewhere kind of thing. just wanna make sure i get it done right.

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Dev RB25 Explorer

Dev RB25

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this is what ive gathered so far.
 

On 27/02/2012 at 6:06 AM, The Dan said:

When I said move it by hand I didn't mean you could grab it with your fingers and turn it lol.

Cam gear on, belt on.........turn the bolt in the centre that holds it on the cam until it's tight. When you turn it further to tension the bolt, the camshaft will turn but the outer gear part will stay still.

You are looking for the wrong problem. The gear will be fine on both

taken from

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Dev RB25 Explorer

Dev RB25

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as that post said, to rotate the cam manually.. i was wondering, if it were to be stuck in advanced.. would it be safe to rotate it anti clockwise (retard) to get it unstuck ? logically im thinking it should be ok.. but dont want wanna be a smartass thought ill check first,

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Dev RB25 Explorer

Dev RB25

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not much help eh .. hahah its ok ..ill just keep this post updated in case anyone is facing the same issue.

today i got the cam covers off... tried moving the intake manifold but the main bolt(after removing the vct cover plate with spring loaded in) and it was not moving. it was stuck. tomorrow ill be removing the timing belt off, and pull the intake pulley out and have a look.

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Dev RB25 Explorer

Dev RB25

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pulled of the intake pulley, noticed in the vct cam gear, small amount of debris, oil inside the gear felt rough. suspect this could have gotten the pulley stuck. got another pulley from a friend on its way. hope this fixes the problem.

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  • 1 month later...
kingtube69 Experienced

kingtube69

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On 11/20/2016 at 10:50 PM, Dev RB25 said:

pulled of the intake pulley, noticed in the vct cam gear, small amount of debris, oil inside the gear felt rough. suspect this could have gotten the pulley stuck. got another pulley from a friend on its way. hope this fixes the problem.

Did you end up working this one out mate?

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