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bens4s

throttle jack question

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Hello,

I have bypassed my throttle jack capsule... Kind of.

I disconnected the vac hose from the relay and capped it. I also strapped the bar to the intake, all the way up. Since I have not removed the capsule, rod, or valve did I actually bypassed it entirely? I have removed components from the exhaust as well. I understand it may not be the safest option. Im just wondering if I actually made a difference?

Thanks for your help.

Edited by bens4s

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Are you asking about the Throttle Jack (which increases speed with the A/C compressor engaged) or the EBPV (Exhaust Back Pressure Valve) which closes the exhaust during warmup?

 

If you disconnect the vacuum source from the EBPV, you need to wire it in the OPEN position, otherwise you will choke the exhaust over ~3000 RPM.

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As I understood it the ebpv and throttle jack capsule are engaged at startup to warm up the cat. The ebpv is gone and I read a post that I should also remove the throttle jack capsule. Im not sure if its what you stated. Its a 95 s4s USA model. There's no wires going to it, Just vacuum.

Edited by bens4s

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Yes Ben, from your description it sounds like you have effectively disabled the throttle jack. By disconnecting the vacuum, it shouldn't operate. Fixing the linkage is done so there is no risk of interference with the lever for the trottle. You just need to make sure it can't move and let's the throttle close fully. I had done the same on mine, until I had the engine out and had easy access to remove capsule, rod, lever etc completely.

 

Filip

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Does the throttle jack have anything to do with the air-conditioning? I thought it was just for the EBP valve? It's disconnected on my car (there's no EBP valve when I bought it) but it does have air-con fitted.

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It should  raise the revs slightly when the ac is put on as well.

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The throttle jack has no relation to the A/c on our cars.

It all relates to the Exhaust emission control US spec I think.

The EBPV closes to keep exhaust gas in the cat as to allow it to get to it's optimum operating temperature quicker. The throttle jack opens the throttle so the engine doesn't choke and keep cutting out while this is happening.

Stripped all mine out. Disconnected solenoids, vacuum lines capped and mechanical parts removed. Never has a moments trouble.

It's correct to state that the EBPV should be wired open or removed if disconnected. You can by a spacer that fits in between the two exhaust flared ends if you remove it.

Wayne

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Also I'm speaking in relation to fuel injection cars.

Can't speak for carb turbo models.

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I wouldn't recommend the spacer - I found it impossible to seal it satisfactorily given my original cat/backbox combo....

 

But no the ECU alone raises the revs when the AC is engaged.

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Two conflicting reports!

 

I searched through the service notes this morning, and couldn't see any connection from the A/C to the throttle jack. It looks to me as though it's purely for EBPV purposes, but no doubt someone will confirm that.

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Sorry forgot yours is a later car. Mine is carb n/a where it triggers on over run, ac and choke.

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Thought I had confirmed that Ian. If your car is an injection model ie SE or later the throttle jack has no impact on the A/C. :-)

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The throttle jack on the carb engine is there to increase the revs when additional demand is put on the engine. This normally means but not exclusively when the aircon is switched on. But it is not connected or wired into the aircon.

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