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620 throttle problem


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so ive had my 620 sitting for a week or two while i was getting my maxima together, now its time to get working on my 620. finally moved it today, it was fine when i first started it but by the time i drove it into my garage it was acting up.

when i turn the car on it starts idling higher and higher as if i was pressing on the gas but im not.. i even disconected the throttle cable from the carb but no change....

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On EFI cars the fuel ratio can easily be adjusted automatically by the computer. Cold engines are less efficient and do not run well on the theoretical stoichiometric 14 to 1 air fuel mixture. On carb equipped motors a mechanical plate partially covers the air inlet which increases the venturi vacuum and draws in more fuel. To aid in the warm up, a fast idle is employed to add more air to the extra fuel. The engine revs up and warms up faster. The choke is so designed to slowly turn off and lower the fast idle as this happens. For example the L20B fast idle is expected to be between 1,800 and 2,300 RPM and sometimes can seem excessive. To release the fast idle just lightly tap the throttle peddle.

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the choke may be bad, on my 620 there are 3 screws that hold the auto choke assy and you can adjust it. When cold the plate should be basically closed, a couple minutes after running the plate should be straight up and down. Mine is bad, I adjusted it to straight up and down and just let it warm up for a while now.

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