[BROWN TROUT]

This is on my 88 2.9 V6 Ranger speed density.

Gets 20mpg when the ambient temp is above 80 or so, but goes to 16mpg as soon as fall arrives.

I know, I could move to Florida, but I like fall.

I have checked voltages on the ACT and the ECT sensors and everything seems good. This will be the third year with the same problem. First year I was in denial, second year I was in Roadster build mode, so this year I need to fix it.

Any ideas?

Thanks

 

[Robert Duncan]

Might need a new thermostat.

 

[Steve]

Since it's an 88, I'll take a guess and say Oxygen sensors.

 

[RacingRob]

Where you live, do they switch over to the oxygenated(sp?) or blended fuel for the Fall/Winter months?
They do up here and I can really notice a difference in gas mileage.
RR

 

[Wade Chamberlain]

I'm w/ RR. Same here.

 

[Cardiac]

Originally posted by BROWN TROUT:
This is on my 88 2.9 V6 Ranger speed density.

Gets 20mpg when the ambient temp is above 80 or so, but goes to 16mpg as soon as fall arrives.

I know, I could move to Florida, but I like fall.

I have checked voltages on the ACT and the ECT sensors and everything seems good. This will be the third year with the same problem. First year I was in denial, second year I was in Roadster build mode, so this year I need to fix it.

Any ideas?

Thanks

I'll second the Thermostat - if it doesn't get hot enough, (180 in a 5.0 application I think - not sure about the Ranger, but probably similar) it will stay in the cold start map and run rich all of the time. Put a 180 or 190 thermostat in.

John

 

[BROWN TROUT]

Thermostat is 192 degree and I know it is working correctly because I have an add on mechanical gauge.

I tried a new oxygen sensor, no different.

No codes.

The fuel thing has me thinking.... Do they really change the gas this far south? I do know that they do NOT change the diesel to #1 like they do up north in winter. I will check into it with my local petroleum engineer.

 

[Todd]

I live in Nevada and they go to oxegenated gas at the end of October, My mazda goes from 30 to 25 mpg, for about 6 month's every year just like clock work. If you read on the pumps they will tell you when they go to oxegenated gas.

The real cool part is that prices stay the same which means we are still paying more at the pump by about 10-12%, since we have to gas up more.

Check all of the pumps next time you get gas if they switch you will see something.

 

[Odrapnew]

Brown,
I know how you feel, my 2001 Ranger did the exact same thing about a month ago. Mine went from 18 to 15. It sux. I would have to agree with rob and wade. I'll check the pumps when I fill up again.

 

[CobraDreaming]

Here in the Dallas area we have a nasty additive called MTBE. Decreased my gas milage about 4-5 per gallon. Suppossed to clean up the air, haven't any difference. So...I get to pay more at the pump for the additive, more because my mileage has decreased, breathe the same dirty are and get to drink MTBE because it accumalates in the ground water. Sounds like a win-win to me