Runs OK when cold, damp, or rainy. No power when air temp is warm (>80)and
engine has run about 30 minutes until I disconnect the line from the MAP
sensor, then it has power but surges when idling. Fuel filter, air
filter, MAP, MTS, and CTS are new. Temp gauge is reading normal. In
mornings when temp is cool, I'm getting 21 to 22 mpg, with MAP
disconnected, it gets ~16mpg.
Why would disconnecting the MAP sensor when temp is warm restore power,
but lower mpg?

"bille" wrote:
>Runs OK when cold, damp, or rainy. No power when air temp is warm
>(>80)and
>engine has run about 30 minutes until I disconnect the line from the
>MAP
>sensor, then it has power but surges when idling. Fuel filter, air
>filter, MAP, MTS, and CTS are new. Temp gauge is reading normal. In
>mornings when temp is cool, I’m getting 21 to 22 mpg, with MAP
>disconnected, it gets ~16mpg.
>Why would disconnecting the MAP sensor when temp is warm restore
>power,
>but lower mpg?
Because you have a intake air leak causing lean mixture untill you
un-plug the mapp.

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