Sup guys,

I recently did a cat-back on the Ranger, idk original exhaust size, but I went 2.5in from the cats back, its a Flowmaster super 44, when I first did this I noticed maybe a 10 mile difference in drop from a full tank from the stock exhaust, now i'm noticing that I went from a good 17-18 MPG, to about 11-12. I'm wondering if it is the exhaust? and if so how come it took about a month or 2 to notice a difference? Or what else could be an issue? I heard the cat might be starting to get clogged? I'm thinking about swapping oxygen sensors? Any help or ideas i would appreciate, thanks guys!

__________________

Try and get your hands on a scanner that reads live data and look at what your measured fuel ratio is, there is two readings ,Commanded fuel air ratio and measured or actual fuel ratio, should be 14.7:1....
At the sametime look at the O2 % readings, and post your readings .

__________________
2011 Ranger XLT 2x4,4.0 SOHC, 5 Speed Auto, 3.55 Rear. Oxford White.

Simplicity is the ultimate sophistication.

Torque it down till it breaks off, then back it off 1/4 turn.

For sure, I will get you these readings by tomorrow night. my scanner doesnt do live data, but at work we have one. thank you

__________________

Oh, I forgot ,take a look at Long term and Short term fuel trims too !!

My last post I asked for o2% ,I meant O2 volts ,should be swinging from 0.15v to 0.85v on the up stream O2s

__________________
2011 Ranger XLT 2x4,4.0 SOHC, 5 Speed Auto, 3.55 Rear. Oxford White.

Simplicity is the ultimate sophistication.

Torque it down till it breaks off, then back it off 1/4 turn.

More air flowing threw the engine. More fuel burned

When working on smal 50cc motors this was really noticeable

Small things like removing air filter required re jetting the carb

lol wut? Exhaust would not affect this.

Maybe your just a little too heavy on the throttle now that you have exhaust to listen to?

Either that or your EGR isn't opening up enough since it could have less back pressure now.

__________________
2011 Ranger XL Extended cab, 2x4, 2.3 L Duratec, Automatic, Mis-colored Leer camper shell, Ultragauge, LED plate bulbs, DDM "cree" reverse lights. Staying as stock as possible

Ehaust side is just important as intake for making the engine breath

U can put a super charger on it but with 2 inch exhaust it'll be like breathing out a straw

Vehicle is not equipped with this part.

A factory engine does not need exhaust to "breathe" better. It has more than enough breath, both on exhaust and intake.

__________________
2011 Ranger XL Extended cab, 2x4, 2.3 L Duratec, Automatic, Mis-colored Leer camper shell, Ultragauge, LED plate bulbs, DDM "cree" reverse lights. Staying as stock as possible

So if I put a smaller header and one inch exhaust it won't affect my engine performance ? Cool never knew that

Run out of "logic" I see

__________________
2011 Ranger XL Extended cab, 2x4, 2.3 L Duratec, Automatic, Mis-colored Leer camper shell, Ultragauge, LED plate bulbs, DDM "cree" reverse lights. Staying as stock as possible

No. Just too lazy to troll you now that you told me changing exhaust doesn't effect how your truck breaths

Whatever you have to tell yourself dude.

__________________
2011 Ranger XL Extended cab, 2x4, 2.3 L Duratec, Automatic, Mis-colored Leer camper shell, Ultragauge, LED plate bulbs, DDM "cree" reverse lights. Staying as stock as possible

It was at like .635 - .813 volts I believe..

__________________

It sounds like it's biased rich. It should be switching down to about .2 volts and then back up to .8.

If you readings are correct, i'm really surprised you haven't set a code.

__________________
2011 Ranger XL Extended cab, 2x4, 2.3 L Duratec, Automatic, Mis-colored Leer camper shell, Ultragauge, LED plate bulbs, DDM "cree" reverse lights. Staying as stock as possible

This my thinking too, the lower reading is too high!! Where's the codes? At least pending codes!!??
It should have not passed the I/M readiness test,

Did you get a look at the measured fuel ratio??

What does the short term fuel trim look like, should not greater than +- 10% swings

And do you have something as simple as a dirty MAF sensor causing this or vacuum leak causing the ECM to command a RICH condition to compensate..

__________________
2011 Ranger XLT 2x4,4.0 SOHC, 5 Speed Auto, 3.55 Rear. Oxford White.

Simplicity is the ultimate sophistication.

Torque it down till it breaks off, then back it off 1/4 turn.