[Jeffescortlx]

Common causes of poor gas mileage:

Engine:

Dirty or bad MAF Sensor (SOHC).

Lazy O2 sensor (pre cat). Does'nt allways trip the CEL right away.

ECT (Engine Coolent Temp Sensor)
Or poor engine temp - runs too cool, ECU never see's closed loop. (See common problem thread for thermostat housing problem for SOHC)

Under performing ignition system. Time for new plugs and wires.

Internal Engine Problem. Compression check might be in order.

Tranny:
Overdrive torque converter lock up problems.

Rolling Resistance:

Under Inflated Tires.

Poor alignment.

Dragging brakes.

Bad Wheel Bearing.

Junk in the truck.

The 1991-1996 models are prone to fuel leaks at the filler hose and fuel pump gasket areas. That could easily reduce gas mileage.

If I missed any thing feel free to post up and I'll add it.

 

[juggalo]

IAT sensor. when that goes bad u'll be runnin horribly rich.

 

[Jeffescortlx]

IAT sensor. when that goes bad u'll be runnin horribly rich.

The IAT sensor is tied into ignition timing.
The MAF, O2 and ECT are the needed sensors for AFR.

 

[juggalo]

well i did notice a big drop in gas milage when mine stopped workin.

 

[Jeffescortlx]

well i did notice a big drop in gas milage when mine stopped workin.

With less timing you lost over all power efficiency. So you have to give it more gas to get the same power, and that made your MPG get worse. But the IAT sensor is'nt directly related to how long the injectors are open for.

 

[oldfordisbetter]

im averaging 26.6 mpg.. mostly highway like a 70/30...no cel, fresh tuneup, oil change, fluid change. does have 329,000 miles on my 97..normal or what can i do to get more?

 

[madmatt2024]

Is it an auto or manual? At that mileage a new O2 sensor and cleaning them MAF is in order.

 

[oldfordisbetter]

5spd.

 

[madmatt2024]

Then you should definitely be doing better but at that mileage expect some reduction. If the trans fluid is still the original I would change that as well.

 

[zzyzzx]

The 1991-1996 models are prone to fuel leaks at the filler hose and fuel pump gasket areas. That could easily reduce gas mileage.

 

[juggalo]

^at 150k miles, i haven't had a leak yet

 

[cklaubur]

Another thing to check, at least on the 1.9L and the 2.0 SPI: the crankshaft balancer. Play in the balancer will throw off the spark timing.

Casey

 

[zzyzzx]

^at 150k miles, i haven't had a leak yet

At 193K neither have I. I haven't had the lock cylinder problem or my heater core go bad yet, but if I keep the car long enough, I will probably get both. Just seems that a mention of that common problem belonged in this thread, even though the smell of gas is probably obvious.

 

[faizy]

Tranny:
Overdrive torque converter lock up problems.

i've pretty much done everything else, except, i dont know how to take care of this one.. mechanic who was doing certification told me i have a tc problem, but other than that, i dont know what i should do about it ..

picking from stop to cruising speeds i DO feel car's been dragging.. its 98 3rd gen automatic..

after an air intake, post o2 (defective) sensor replacement, and replacing clogged+cracked catalytic converter, and new muffler, it runs better, but original "feeling" remains..

 

[UsedTampon]

I get half a tank in 300 KMs with my 97 escort LX auto.

I just replaced the 02 sensor, didn't seem to help much. I was told it's the gas tank that makes the gas fall on its face after half a tank.

 

[Silex]

im averaging 26.6 mpg.. mostly highway like a 70/30...no cel, fresh tuneup, oil change, fluid change. does have 329,000 miles on my 97..normal or what can i do to get more?

i got mid 30's when i towed my wagon home with my 3rd gen , my best so far was 810km to a tank thats 5.06 L/100km or 46.47 MPG !!

keep the fluids up to date , air filter clean , decent plugs , wires , tires properly inflated and leave the lead boots at home ... an NO higher octane fuels will NOT increase your MPG . 87 is fine.

my ONLY mod is a SRI ( short ram intake )

 

[Guest]

Another thing to check, at least on the 1.9L and the 2.0 SPI: the crankshaft balancer. Play in the balancerugg toast will throw off the spark timing.

 

[Green91Goblin]

What about the BP? I put 15 in it yesterday, and I'm already down on E again, with minimal romping.

 

[Emdog]

o2 sensor

I want to replace my 2nd o2 sensor i havnt found it but i have been told there is 2 sensors. i have a 1991 ford escort lx with a 1.9L i replaced the first one in line (before cady right by cooling fan) a photo would be greatly appreciated.

 

[madmatt2024]

There is no 2nd o2 sensor on a 91 Escort and even if there was there is no point in changing it unless your computer is throwing a catalyst efficiency code.