My MPG used to be about 38 or so, now I'm down to 32.

Over the last 6 months, I've done thermostat, plugs and a fuel filter. The cap and wires looked newer so I didn't mess with them after I inspected them.

Today, I replaced a collapsed PCV tube and cleaned out the valve itself, confirmed it's still functioning. Also replaced the air filter but it really didn't look like it was needed.

I'm going to go ahead and throw some wires, engine temp sensor, an 02 sensor and another fuel filter hoping that something is going to cure this.

I'm not getting a CEL and there's no lights flashing on the ECU.

Just to see what would happen, I unplugged the 02 sensor and let it idle for a minute to see if it would throw a CEL or trigger the ECU and it didn't do anything.............I found this a little odd.

Will a bad 02 sensor trigger a light on these golden oldies?

It starts fine, idles good and runs great...............I'm a little baffled by the loss in MPG.

 

Bump

 

Just an update in case anyone stumbles upon this while googling since actual activity on this forum seems all but dead now...........

My mechanic changed out my O2 sensor and found my cat completely melted and plugged.

This accounts for poor acceleration and a big loss in fuel mileage.

I've always thought it was a little doggy in 1st and 2nd when you first start out in those gears, I'll bet this makes it a lot better once he smashes that crap out of there.