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Discussion Starter #1
Renee's '65 289 C4 2100
six months ago, the car started idleing bad. Turned out that passiger side of carb wasn't working at idle. I figured crud in the circuit. Rebuilt the carb and the problem went away. Three months ago, same problem back again. I pulled the carb, suspecting warped base, and swapped it for a spare I had. Problem fixed. Two weeks ago, problem comes back. I found loose intake bolts, figured they were the problem, tightened them up and car runs great. Last week, problem comes back. It acts like a classic vacuum leak. #1,4,6&7 don't contribute at idle. A squirt of carb cleaner, into passenger side of 2100 and the idle speed jumps up. I checked the PCV valve, vac advance, vacuum modulator for leaks. None found. I squirted carb cleaner everywhere trying to find leak. No leak found.

So... I suspect intake manifold leak in the valley area. Thats why I can't find it from the top. Any other ideas?
ty
Eric
 
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If there is a leak from the lifter valley,you can sometimes proof it by checking spark plugs. If one or more plugs exhibit more oil than the others (everything else being equal) you probably have a bad or mis-installed gasket. This just happened to me. Best regards John Las Vegas
 

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Try shooting some carb cleaner through the air bleeds.They are tiny orifices in the booster venturi assembly.Two face straight up,two are angled outward toward the choke housing,if I remember correctly.Use the plastic pipe that comes with the can and hold it tightly to the hole,and using short blasts.One last thought,how did you determine that 1,4,6&7 were missing?Did you pull the plugs while the engine was running?Keep us posted..
 

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Hey Eric,

More crud in the idle circuit perhaps?? You've got a cruddy idle..*G*

It's late but aren't the cyls you noted exactly what's fed by the PS carb bore on a 2V dual plane intake? The fact that the idle jumps up when you add fuel (carb cleaner) to that bore would support that hypothesis....if I'm not all wet on my #'s...

Does the 2100 have the screw in fuel filter on it? Is the flexible hose to it recently replaced?

Let us know what you find out...
 

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Yup, 1,4,6,7 fed from PS side of carb. Fuel pump, with interagal filter replaced, about two weeks ago.
 

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Discussion Starter #6
I pulled the wires and the engine speed did not change.
I will try the carb cleaner. I can also pull the booster venturi after removing the carb top.
 
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