bad mpg (ohv)

[fordexploder_96]

I Have been averaging 11 to 12 mpg. I have done a full tune up, plugs, wires, air filter, fuel filter, pcv, injector cleaner ect... still 11 to 12 mpg im running out of ideas and even at these cheap gas prices the money adds up pretty fast. is there anything else ive overlooked?

 

[corkey]

mas airflow sensor, idle air control valve, throttle body , , clean all of these with a good o2 sensor safe cleaner, that will make a big difference,

 

[96eb96]

mas airflow sensor, idle air control valve, throttle body , , clean all of these with a good o2 sensor safe cleaner, that will make a big difference,

I don't think you can go much over 13 in all street driving on the 96, and that is really taking it easy. Anyway according to my message center. Highway is another story, on a long trip I can get in the low 20s.

 

[aldive]

I don't think you can go much over 13 in all street driving on the 96, and that is really taking it easy.

Nonsense.

 

[aldive]

I Have been averaging 11 to 12 mpg. I have done a full tune up, plugs, wires, air filter, fuel filter, pcv, injector cleaner ect... still 11 to 12 mpg im running out of ideas and even at these cheap gas prices the money adds up pretty fast. is there anything else ive overlooked?

Have you scanned for O2 sensor function?

 

[96eb96]

Nonsense.

This is the OHV remember, and I saw your thread. My scanner(with live stream) reports normal fuel trim and 02 sensor switching. I have royal purple too.

 

[XLT]

I agree with aldive. I had a 93 with the OHV engine in it and i constantly got 15.5 to 16 mpg in the city and that was driving it hard. You could also try using some injector cleaner or running a can of sea foam through the engine as well.

 

[96eb96]

I agree with aldive. I had a 93 with the OHV engine in it and i constantly got 15.5 to 16 mpg in the city and that was driving it hard. You could also try using some injector cleaner or running a can of sea foam through the engine as well.

maybe, i should try that...I just figure its a big vehicle and if it runs well leave it alone.

 

[daan-o]

brakes rubbing?

 

[silky]

I am only getting about 11-12 mpg (300km/tank) in my 98 sport sohc. It doesn't smell like it's running rich or spew out any black smoke or anything.

I have noticed that my speedo is off. I drove by a thing that reads your speed and it said I was diong 50 when my speedo read 55. Would this throw the speedo off? If so, wouldn't it mean I am not even getting 300km/tank..ie because it thinks I am going faster than I am it is hitting 300 when I am actually at like 260?

 

[Blee1099]

A 2nd gen OHV can get over 13 MPG.. My old 97 constantly got 14-16 MPG even with 33s. Its just a matter of driving style, gearing, and vehicle condition. Things like fresh plugs & wires, clean MAF sensor, IAC, etc will help alot.

 

[team]

This is the OHV remember, and I saw your thread. My scanner(with live stream) reports normal fuel trim and 02 sensor switching. I have royal purple too.

what kind of fuel trims are you seeing? ltft and stft?

 

[Cobraguy]

My wife gets 17.5 mpg tank after tank with our 95 OHV. Never fails. And that car hasn't been out of town in I don't know how long. Of course, you have to remember that traffic moves around town here at about 55 mph...or faster. I'm not kidding...

 

[robertoa1a]

I got a '96 5.0 auto trans getting about 18mpg all city driving. I got my girlfriend a '97 4.0 5sp getting about 16mpg. Bouth are XLT's. My trim on the 5.0 averages around 0% (+/- 5%). I don't know about her car because she needs to buy tune-up parts since I paid for the car. She drives a bit more agressive than I do too.

I thought mine was getting good mpg because of the od trans but I think most people don't go all the way with thier tune ups to achieve origonal factory specs(17-21mpg) or better. I got a light foot most of the time.

 

[Glen4X4]

my 96 OHV when I drove it everyday was getting 20mpg highway with her driving its getting 18, and my 95 gets 16mpg they both have same trans/3.55 gearing the 95 has 31" tires and 206,9XX miles and the 96 had 154XXX so you can deffinetely do better gas mileage than what you're getting now. I would run a can of sea foam through the intake, run at least a synthetic blend oil if not switch to complete synthetic.

 

[96eb96]

what kind of fuel trims are you seeing? ltft and stft?

Nothing over say 8%, I will check later though.

 

[fordexploder_96]

02 sensors are operating normaly but it looks like im getting low voltage coming from my DPFE sensor. other than that im coming up blank

 

[96eb96]

Ok, here is what I found, at idle LTFT is steady around 8%+ on both banks (city gas mileage???), STFT is around 0 (maybe +-1). At cruise LTFT drops to and is around -1.5 to + 2 , STFT is around 0 ish. This is kinda ok by the manual I believe. The idle LTFT may be a bit high. If you need more details I can look further at the data.

Very very few misfires, maybe 5 total over 6 cylinders in about 30 minutes, I have a bunch of misfire counters watching. I've seen that amount of misfires in scanning 2008 cars. Idle quality is very good, but I cant say perfect, maybe a bit of vibration at some rpm. Better when warmer.

BARO is reading a bit low (dirty maf?) 156Hz, Ideally should be 159Hz at sea level, but within spec.

IAT agrees with compass thermometer.(41)

ECT was a bit higher at startup (50), but that could have been heat retention from driving not that long ago. ECT follows temp gauge, drops to 179 at lowest point (1/2 way between the C and the thermometer icon), 192 at highest.(center of the thermometer icon). Sorta always was like this, new stat, flushed coolant, bled, etc.

O2 sensors seem very responsive when graphed, fast switching as RPMs increase.

City mileage (lots of stop and go, 2 minute lights etc.) over this 10 mile scan, 12.9 as reported by the computer. I should have had my scan tool monitor gas mileage, it could.

I also have 4.10 gears.

 

[robertoa1a]

The confusing part about those who aren't getting good mpg is; where is the fuel going? It seems to me that it either gets burned efficiently and is converted into power or it goes out the exhaust unburned. If o2 readings are good, then wouldn't that mean that the car isn,t putting the the power to the pavement? In other words shifting later than necessary.

I know these questions are kinda' dealing with the basics but mine gets better mpg than it should and cruises at around 1200-1400rpm and doesn't kick down in gears unless I stomp on one of the pedals. How about you?

 

[96eb96]

The confusing part about those who aren't getting good mpg is; where is the fuel going? It seems to me that it either gets burned efficiently and is converted into power or it goes out the exhaust unburned. If o2 readings are good, then wouldn't that mean that the car isn,t putting the the power to the pavement? In other words shifting later than necessary.

I know these questions are kinda' dealing with the basics but mine gets better mpg than it should and cruises at around 1200-1400rpm and doesn't kick down in gears unless I stomp on one of the pedals. How about you?

Lots of reasons. Say you have dragging brakes, transmission, engine wear etc...more gas has to be used to catch up to the driver demand on the gas pedal. The engine could be working fine, but its like adding another 500lbs of weight to the car.

Also, sensors can be reporting slight misinformation to the computer, and the 14.7:1 air gas ratio is skewed. The computer makes its best guess in that case, so a few MPG are lost. A clogged injector may not be able to feed the engine what the computer requests, or carbon deposits could be absorbing fuel.. so the computer may have to add more gas...you get the idea.