Ok, after messing with a simular issue for about 6 months and never finding this solution on line figured I'd share it as it pretty much matches his issues.
Check your Choke!
Someone on my car connected the choke line to the Dizy +12vdc so neither were getting the current they needed, meaning the choke did not fully open and what happens when your choke does not open? You run rich and have a lack of O2 when hot and load up the engine when trying to take off, car sounds like a lawn mower ect....
Hope this helps someone.
Ken
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