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Lost MPG???


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Ok, I have a 1988 GL10 Full time 4wd EA82 turbo 5-speed. My gas mileage used to average 24-26 mpg and after parking the car while I was out of the country for 18 months I have gotten 15 to 20 mpg over the last 4 tanks of gas. I did put some fuel conditioner in before I parked it and I ran a can of Seafoam through it after starting it back up 2 months ago. I also run the Lucas upper cylinder additive with every tank of gas. My check engine light is not on.

 

I have replaced the following parts along with cleaning the MAF sensor:

Spark plugs, wires, cap, rotor, PCV valve, fuel filter, air filter, gas cap, O2 sensor

 

What else could be affecting my gas mileage?

 

The O2 sensor wiring was cut and spliced by the previous owner, so how important is the shielding on the wire from the computer? The new O2 sensor doesn't appear to have any shielding?

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Have you checked the tire pressures? I've found that by the time mine looked noticeably low, on the '89 GL wagon, I'd shaved my mileage from 28 average to 22ish. Oops.

 

You've already replaced everything else I'd have suggested... so I'm not sure what else ???

 

As far as the O2 sensor, I've had a check engine light for that on for two years on the wagon, and it still averages 26 to 29mpg, and 31mpg on the highway. It seems to have jumped about 1mpg when I replaced the rotor and plugs though (the rotor and cap were both noticeably burnt after 50k miles).

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Have you seafoamed your oil and then changed it?

If not, I would recommend pouring about half a can into the oil and the other

half into the gas tank.

Run it for 5-10 min with the seafoam oil, then drain it and fill with new oil of your

choice. (My brat seems to do best with 10-40w)

Hopefully this helps!

 

Twitch

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