Intake Venturi Problem

[YEOH250SL]

Hello, I have started with the linkage tour today. At step 1, I already ran into a problem. I know I need to adjust the venturi so that the butterfly almost bind. However, when I adjust the stop screw, even back it out all the way, no position would bind it. It was just loose at all positions. I was trying to find a sticking point and plan to slowly turn in to achieve what is described in the linkage tour. May I know what is the problem?

Thank You

[TJMart]

You may want to check the 2 screws that hold the butterfly to the shaft that runs through the throttle body
and make sure the butterfly is secure.

[ja17]

Is your pagoda an automatic transmission? If it is, your electrical switch of the other side of the venturi may need to be loosened (two screws) to allow the venturi to close fully. Make sure the linkage rod going to the venturi is disconnected before you adjust the stop screw.

[YEOH250SL]

Really appreciated the input. I will give it a try tomorrow when I get back to the car.

[YEOH250SL]

TJ,

I would probable need to remove the throttle body in order to check the screws, right?

[YEOH250SL]

Joe,

My car is an automatic, and as you said, it has the switch on the other side. So, I will loosen the screw to try to close the butterfly. If that's the case, I will resecure the switch once I get it completely closed?

Thanks.

[TJMart]

TJ,

I would probable need to remove the throttle body in order to check the screws, right?

No you can just take off the large hose in the front of the throttle body that goes to the air filter canister.

Take a look at this video:      https://www.youtube.com/watch?v=s9pqlRglL0s

Tony

[ja17]

The mounting holes for the switch are slotted to allow the plastic switch to rotate, for adjustment. I would just loosen them up first. Then check to see if your venturi flap closes all the way. You should be able to feel it binding in the venturi after you push it closed all the way (linkage rod at the venturi disconnected). Next set the slotted screw and 10mm lock nut, just enough to keep the venturi from binding, then lock it in place. Linkage rod can now be connected as long as it does not change the position of the venturi flap. If it doesn't line up, run through the linkage tour again and then adjust the rod going to the venturi so it just slips onto the linkage ball, without moving the venturi linkage lever. The electrical switch should now be adjusted so it is closed (permitting passage of voltage) at idle and up to approx 1500 rpms. Tighten  the two screws down once the switch is adjusted. AT 1500 rpms the swich should open (not permitting voltage to pass). Correct adjustment of the switch is needed as it controls the modulator pressure in the transmission for smooth downshift before stopping. It also raises modulator pressure for slip free acceleration.

[YEOH250SL]

TJ, I checked the screws and it was tight. Thanks for the tip anyways.

Joe, i loosen the switch and it did the job. The venturi now closes! Now how do I adjust the electrical switch? Thanks for everything

[Pawel66]

When you type in, in parenthesis, "throttle switch adjustment" in the search window, you will receive a lot of hits, this one for example: https://www.sl113.org/forums/index.php?topic=26120.msg188454#msg188454

or

https://www.sl113.org/forums/index.php?topic=30906.msg224337#msg224337

[YEOH250SL]

Pawel,

Thanks for the tip. I'm such a novice and didn't even know what's the name of the switch. Now I know. Much appreciated.