Questions about MPG...

[BlackDog]

Buy this Bronc in May, spend 600 or 800 dollars getting it dialed in to where it is daily driver dependable, new wheel bearings, inner and outer, new plugs cap wires, rotor, new brakes and a caliper, new clutch master and slave cylinders... e-fans... radiator, re-did all the grounds, new alternator... synth blend oil, fuel system cleaners, ATF and H2o down intake manifold to clean it out... (and then new plugs agin' after the ATF and H2O just in case they were fouled....)
High flow air intake with K&N on the end of it, $40 on the K&n filter care package, the cleaner goo and the re oil stuff..., new pcv... timed to the best of my abilities... mark has moved, something to the effect of a rubber dealy in between the two pieces of metal, crank on one side and actual balancer on the other side....rubber twists, marks get all fubarred, 327 Chevys had the same problem I guess...

I am getting 10.2 mpg out of my EFI 300 cid 6 cylinder... with a 3speed manual tranny that has O/D, as in 1,2,3,o/d.

It runs as smooth as anything on a new car lot...

Oh yeah, 31" wildcat LT's on factory spoke whels, with 3.54 gears...

Haven't changed: O2 sensor; EGR; MAF....

Does occasionally flutter at idle...... No codes are present.

WTF am I not doing?

(Highlighted problem I want addressed)

 

[red]

is your foot through the floorboards? other than that the only things i can think of are:
1. O2 sensor is gone
2. tranny slipping really bad.
3. cat plugged up or some other exhaust restriction

 

[BlackDog]

Nah, I shift between 1500 and 2500, depending on what my final speed will be. In town, 1500, hitting the freeway, 25-2700.
Clutch is done, but no ssssslippage. On floor, and stif, but it full engages and disengages.

Might try hollowing out the cat, no smog here yet, it doesn't sound or feel restricted, seet I dunno, that might be it. Guess I could pull the o2, and wire brush it... may have some serious build up, I was getting 15 in the summer, and now it has dropped, I did "loan" it out to my nephew for the last few months, but it sat more than got drove, and when I got it back, it had dropped to 13, and now 10... acredit winter mpg drop for some of it, slower speeds, spinning out, longer idle times, etc. but the point still remains that I had an efi 460 with rings so bad it consumed a quart every 150 miles or so, do 12 consistently....

 

[Spork]

odometer correct? Check with GPS?

 

[RockMonkey]

A bad O2 sensor could cause it to run rich which would affect your fuel consumption, and then add in the additional idle time, cold weather warm-up delay, and everything else that drops your MPG in the winter. Does the engine warm up all the way? A stuck open thermostat could keep the engine from ever getting up to operating temp, especially in the winter. That would also affect MPG.

 

[BlackDog]

I have discoed the e-fans, and never run more than a 1/3 of the gauge... might not be warm enough, but thought it was okay... Gonna pull the o2, and at least clean it off,(wire brush the dog snot out of it) seemingly I have read that helps, in between paychecks, so throwing money at it, at least for a short spell, is out.

 

[BlackDog]

odometer correct? Check with GPS?

Yeah, read 68 on the freeway the other day, got pulled over for not seatbelting.... he said I was doing 70, so If it reads 68, and ISP reads 70, and I am running 7% or whatever over stock in tires, I am gonna say pretty close to dead on.

 

[RockMonkey]

I have discoed the e-fans, and never run more than a 1/3 of the gauge... might not be warm enough, but thought it was okay... Gonna pull the o2, and at least clean it off,(wire brush the dog snot out of it) seemingly I have read that helps, in between paychecks, so throwing money at it, at least for a short spell, is out.

Sounds like it's not warming up properly. I'd replace the thermostat with the OEM correct part. I betcha losing 5 miles per gallon over a tank of gas costs more than a thermostat.

 

[BlackDog]

totally, think I replaced that, but will throw another 5 or 6 bucks at a t-stat.

 

[red]

how much does your 02 sensor cost? usually just replace them unless they're kinda pricy (usually 4 or 5 bucks in my experiance).

 

[gijohn40]

my expedition has 4 o2 sensors and every one of them cost $55 or more... and they seem to go out about once a year... I have yet to see one cost only 5-10 bucks...

 

[red]

the ones in my old 89 suburban, only 2 of them. replaced them when i lived in midland.

 

[BlackDog]

45 for o2, payday, 90 for harmonic balancer, payday as well.

 

[BlackDog]

so i did the t-stat today, thinking I might be running w/o one, had an overheating issue last summer and was foggy as to whether I put one in or not, gauge goes to about a third, idle it for two hours, 75 on freeway, or stop and go, hits a third or a quarter and thats it, no fans running ever.

Turns out I had a 180 degree t-stat in there, OEM is 192, I bought a 195 and this is how that job went:
you can see I was using a monster ratchet, best $8 I have ever spent in my life, Pep Boys in Orem... 2004, not capable of the highest torque specs though, the Camels are there to illustrate is stubbiness.

 

[erocrocks]

WHAT DID YOU DOOOO!!!!!?!?????? that sucks, a simple repair turns into a $$$$ one


kinda off subject but not all the way....... i hava a 92 wrangler i6, i put a 180 t stat in mine to help with summer driving, does it really matter that much , the temp differnce in t stats?? i beleive mine is sopposed to be around 190+


any thoughts

 

[krawlereng]

with fuel injection you want to stay close to stock thermostat temp. if you go too cold the motor will run too rich.

 

[BlackDog]

WHAT DID YOU DOOOO!!!!!?!?????? that sucks, a simple repair turns into a $$$$ one

does it really matter that much , the temp differnce in t stats?? i beleive mine is sopposed to be around 190+


any thoughts

Still have no idea what I did, read the last pic.... chinese iron and ford.. I think that was the root.

Now to the temp mattering question...

I was running 180, and all my ford guru's screamed up and down that that was too cold, it needed at least to be at the OEM 192 to hit peak efficiency, and the one guy said that even after it had the 195 in it, my gauge reading was lower than it needs to be for optimum efficiency, and that I should put cardboard in front of the radiator to get the gauge to read in the 55-60% range...

So yeah, 20 voices screaming that the motor needs to be at 200 degrees or so to be efficient would lead me to believe that you might have an issue.. But my XJ always ran 210 or so, so you might be okay... just cause you have a 180, doesn't mean necessarily that is where you are running.

I can't make this get hot, towing itself, idling for hours, driving hard, 1/3 of the gauge, and that is it. (no fans).