High Engine Idle Speed After Coming off Cruising Speed

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Viper
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Re: High Engine Idle Speed After Coming off Cruising Speed

Post by Viper »

Could be a few things. I'm assuming TBI? Wonder if the TPS gets out of range during operation.

One of the benefits of having twins when diagnosing is that you can swap hardware and see if the fault follows the part. Guess we'll have to wait and revisit in the Spring :banghead:
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Scurvy Dog
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Re: High Engine Idle Speed After Coming off Cruising Speed

Post by RSS »

Update. I think my high idle problem is finally solved. Secondary barrel butterfly was sticking open very slightly that I didn't notice before (1/16th inch maximum). A good inside and outside carburetor cleaning with carburetor/choke cleaner seems to have fixed the problem. I have powered up to full power cruising speed three times in a row now and engines went back down to normal idle speed when backing off the throttles. Therefore, I'm declaring problem solved! Thanks for everyone's help.
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Re: High Engine Idle Speed After Coming off Cruising Speed

Post by bud37 »

Good catch..thanks for posting the fix....... :beergood:
FWIW.....The above is just my opinion.
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