neo1967

I cleaned the throttle bodies and MAF sensor this weekend now it seems as if I am getting poor gas mileage? Is it common to get lower gas mileage after cleaning? Throttle response is quicker and less hesitation and cold start idle remained the same.
Is there something else I need to do?

NisCal17

I think your MAF is malfunctioning. I know that if MAF is working incorrectly the car will run rich.

compyelc4

Why did you find it necessary to clean the TB and MAF? Curious.

The Wizard

iTrader: (43)

My thoughts exactly. The MAF is a very sensitive piece of equipment. I wouldn't clean it unless it was known to be contaminated with oil vapors etc (assuming an oiled K&N filter was in use).

wild willy2

It's a very easy clean, just do not touch it!!

neo1967

No just used a Mass Air flow sensor cleaner to clean the mass air flow sensor.
The throttle bodies were dirty and I was getting hesitation and poor throttle response so cleaning the throttle bodies definitely made a difference in performance.
Just the lower gas mileage is now an issue.
.

Sugardaddy1979

What temperatures are you driving in? Colder weather can reduce fuel economy.

neo1967

80-90 degrees

MONTE 01&97 SE

iTrader: (1)

Could be a result of the below:
https://www.bellperformance.com/blog...blend-gasoline

Blame The Winter Blend Gasoline. ... Winter gas is more volatile and evaporates more quickly, so it is ideal for it is used in the colder air of winter. In terms of gas mileage, you get better mileage on summer blends than winter blends because the summer blend gasoline has about 2% greater energy value than winter blend.Dec 2, 2010

neo1967

Do you think doing a Accelerator pedal released position learning, throttle valve closed position learning and idle air volume learning would fix the issue?
Disconnect the battery?

Richard66

"It seems as if I am getting poor gas mileage" You didn't post any numbers on mileage or how you figure it. Your cleaning was done on the same weekend as your reported low mileage, not nearly long enough run time to get a accurate reading on fuel usage. The most accurate reading comes by the manual method of fuel used divided into miles driven.

Steptide

I use non ethanol gas, and in winter my gas mileage is always worse than summer. Some due to letting my car warm up, and some due to the fact that your car just gets worse gas mileage in the cold. Don't forget, using heat, rear defrost, heated seats/steering wheel, all contributes to worse gas mileage. Also tire pressures in the winter will almost always be lower than in summer. Even if your tires are at the right pressure, the summer heat will raise the pressure automatically and will give you slightly better gas mileage
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compyelc4

Op said his is in 80-90 degree weather, not cold winter.