Did you not set the timing with a timing light? If you don't have the timing set properly you'll be chasing problems that are a byproduct of incorrect timing all day.
MONTE CARLO Need info on vacuum switches
- Thread starter Bludacious
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Timing has been set with the advance line disconnected (and plugged) with a timing light, IIRC it's advanced by about 8 degrees.
I think you may be going down a rabbit hole. The only reason the vacuum advance is there for is mileage. If it makes a difference maybe you have too much timing. I am thinking choke issues also.
Automobile engines operated for decades without TVS in the system, I question whether the carb on the car is correctly set up, including lack of vacuum leaks, choke settings, and fast idle adjustment
If you told us whether the carb had been changed to a non computer version or not, I missed it.
With emissions removed, a non CCC carb, and a non computer distributor you would essentially have a lower-compression version of a late 60's/very early 70's 49-state SBC
Never had an issue with that setup even when I lived in Iowa, just depress the pedal once to close choke, crank, and when it starts, and runs for a few minutes to get some heat in the engine, a slight tap on the pedal kicks it off of high idle
If you told us whether the carb had been changed to a non computer version or not, I missed it.
With emissions removed, a non CCC carb, and a non computer distributor you would essentially have a lower-compression version of a late 60's/very early 70's 49-state SBC
Never had an issue with that setup even when I lived in Iowa, just depress the pedal once to close choke, crank, and when it starts, and runs for a few minutes to get some heat in the engine, a slight tap on the pedal kicks it off of high idle
The carburetor and distributor have both been changed, fast idle has been adjusted and I have checked for vacuum leaks using a can of carb cleaner. When I adjusted the timing I just looped the line over to a spare unused port off the carb which was and still is capped. Also I do want the TVS to help economy, the only reason I even swapped out the carb and distributor in the first place was because the original one desperately needed a rebuild and since the ECU died it ran pig rich and gave horrible mileage. The choke thermostat operates just as it is supposed to and I always prime the engine with 2 or 3 pumps of the gas pedal when it is cold.
Of course it did. You have an incorrectly adjusted vacuum pull-off causing the rich condition. The vacuum leak added air which masked the condition. Remove the leak and you are back to a rich condition. When the choke opens fully the condition disappears. You need to adjust the vacuum pull-off and verify it opens as soon as the engine starts. Fully open it should be between 1/8 and 1/4" open at the butterfly. Check an older Motor manual or Chilton's for the opening on an old engine similar to yours. Later models used an angle gauge which no one has so go by the old specs. Measure yours and open it by adjusting the spring loaded screw on the linkage.
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