Jenvey Throttle body not closing

[angus337]

Just fitted a jenvey twin throttle body to my TVR chimaera, but having an issue with it staying open on deceleration.

With the engine off it seems fine. However, with the engine running, it doesn’t close fully and remains partially open, between 5 and 15% indicated on the ECU. Feels like it is being held open by the air flow to the plenum.

It was a second hand part so I’ve replaced the springs on the throttle and linkage and cleaned everything but still having the same issue.

Just wondering how easy it would be to strip down and lubricant these. Or is it a better bet just to send them away for servicing.

[Boosted LS1]

Could you oil the spindle from inside the tb using a syringe and some thin oil?

[227bhp]

Are you sure you've put the springs on correctly?

[DVandrews]

From my experience..

I) possible drag on the cable when engine hot
Ii) throttle position sensor mis mounted, not concentric of pushing on the end of the spindle
Iii) detritus/corrosion on shaft or linkage (soak TB overnight in Jizer bath then lubricate

I have seen the above issues several times.

Dave

[GreenV8S]

I suppose the problem is probably caused by air pressure on the throttle plate. Can you reproduce it engine off by pushing gently on the throttle plate in the direction of air flow as it closes? If so, hopefully that will enable you to locate the source of the friction and know when you've resolved it.