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Since you guys are on the topic of gas mileage, what is the average for a stock '85 4Runner 22re with stock tires. I get about 15 around town and 20 on the hwy. Is that pretty normal? How bad can the Oxygen sensor interfere with mpg?


You are about 3mpgs off on city and about 5-8 off on the hwy from the average. Age/tune-up schedule/driving habits could be the cause of this difference, as well as tire size to gear ratio.

The O2 sensor measures the amnount of oxygen in the exhaust, it basically tries to find the optimum ratio, and will lean/richen the air:fuel ratio. A lazy/failing can allow the mixture to run rich, causing you to use more fuel than you can burn.

More than tread lightly. Leave it like you were never there, nor anyone else.
'90 X-cab 4.88's 33 BFG AT's, rr ARB, Headers, Ignition upgrade, cold air induction.
'91 X-cab 5.29's 315's BFG MT's, rr ARB, custom bumper and flatbed