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Discussion Starter #1
I removed the fuel distributor (FD) and the air meter boot then did a smoke test. It appeared to me that excessive smoke was escaping around the throttle body, possibly at the gasket. Even with the FD and air meter boot removed it was impossible to be certain. I feel confident that the smoke was NOT coming from any of the eight intake manifold intermediate seals.

I removed the throttle body but I have no idea how to test it for leaks? I would greatly appreciate anyone giving me guidance on how to proceed.
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I'm not even sure how the throttle body looks off the car but could you duct tape both sides of the venturi, cap off the vac connections and use one of the vac connections to introduce your smoke?

I've got to say, that is a hilarious pic. "Let me out of here!"
 

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Discussion Starter #3
I did several different smoke test variations and concluded that my throttle body is the cause of the air leak. I also tested my parts vehicle throttle body and it also leaks, although not as profusely. This is understandable since my parts vehicle had the same start issue as by 89. I disassembled one of the throttle bodies hoping to rebuild it but decided that I would purchase a new one from MBOEMPARTS.COM. The price was reasonable and the risk that I would screw it up was huge! The wife is very unhappy and I need to get this vehicle on the road so that I can get out of town.
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Discussion Starter #5
It appeared to me that the leak was from both sides where the shaft pivots. When I disassembled it the rubber seals were badly deteriorated. I made a feeble attempt to remove the needle bearings and quickly decided to just buy a new throttle body.

What adjustments will I need to make once I receive the new throttle body? Several years ago I replaced the sensor and made the adjustment but I am weak when it comes to electronics. I'll gladly take all of the advice I receive from Board members.
 

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It appeared to me that the leak was from both sides where the shaft pivots. When I disassembled it the rubber seals were badly deteriorated. I made a feeble attempt to remove the needle bearings and quickly decided to just buy a new throttle body.

What adjustments will I need to make once I receive the new throttle body? Several years ago I replaced the sensor and made the adjustment but I am weak when it comes to electronics. I'll gladly take all of the advice I receive from Board members.
Here you go, Tom.
 

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Discussion Starter #7
I installed the new throttle body which came with the sensor switch attached. I did a smoke test this morning and no smoke visible in the intake manifold or throttle body areas. Yea!

It will be several weeks before I actually start the vehicle since I am in the middle of HVAC box refresh. I have it removed and on the bench. All parts needed are here and ready to install. Removing the HVAC box scares me to death but I am taking it one step at a time.
 
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