Terrible Gas Milage, please help me fix!

[Nic]

I have a 91 Ranger, 2wd, 4 liter with new air filter and fuel filter and I'm getting 10 mpg. . I was getting 17 only a month ago. Tire pressure is fine...so what's going on?!? Any ideas?

 

[black_demon69]

I have a 91 Ranger, 2wd, 4 liter with new air filter and fuel filter and I'm getting 10 mpg. . I was getting 17 only a month ago. Tire pressure is fine...so what's going on?!? Any ideas?

try new spark plugs and wires also air filter.. could also clean throttle plate and mouth of upper intake... also keep foot out of the floor

 

[Nic]

try new spark plugs and wires also air filter.. could also clean throttle plate and mouth of upper intake... also keep foot out of the floor

I have new spark plugs to, but wires makes sense. Is there any way to check them before I just replace them? I'll try those other things too, thanks! And even driving conservatively I'm getting that ! Foot on floor I get negative ten

 

[griz700rocket]

A bad O2 sensor can cause a rich condition that will decrease fuel mileage.

 

[Nic]

A bad O2 sensor can cause a rich condition that will decrease fuel mileage.

Alright, thanks. How do I check that?..is there a way to?

 

[hank857]

If you dont have a code reader, try one of the auto stores that may have obd 1 capability. If nothing else you can get one fairly cheap to keep. There could be several things as noted, dirty MAF, air filter, some bad sensors, weak coil/coilpac, dont know if yours a distributor or not?

Wires can be checked for resistance but depends on the wires being used. Do a you tube search always someone with how to info.

You can run some SEA FOAM thru the tank and spray some cleaner into the intake but more than likely will need to pull and clean the intake if dirty. Take the air intake hose off and check for dirt carbon on throttle plate that will give some indication. It is also possible to have a bad injector but you would have other indications of it.

 

[black_demon69]

If you dont have a code reader, try one of the auto stores that may have obd 1 capability. If nothing else you can get one fairly cheap to keep. There could be several things as noted, dirty MAF, air filter, some bad sensors, weak coil/coilpac, dont know if yours a distributor or not?

Wires can be checked for resistance but depends on the wires being used. Do a you tube search always someone with how to info.

You can run some SEA FOAM thru the tank and spray some cleaner into the intake but more than likely will need to pull and clean the intake if dirty. Take the air intake hose off and check for dirt carbon on throttle plate that will give some indication. It is also possible to have a bad injector but you would have other indications of it.

no distributor it is edis ign system.. as for wires for me as a matter of me being anal i just replace wires every time i do plugs but thats me. i do this because wires don't cost that much and keeps me from digging back into it a month later possibly! as for suggestions above alll are good just didn't think of all that this when i posted earlier (still hadn't finished my coffee) to save gas you could do the fred flinstone hybrid mod to your truck by cutting a hole in floor for your feet to go through.

 

[jeremysdad]

You can check anything electrical with an ohmmeter and knowledge. Saves money and frustration?

Do they teach 'Derp!' at schools these days? My kids have taken that class, but I swear it wasn't offered in school 20 years ago.

 

[ridgerunner]

I don't know where U live but here in the NE winter blended fuel drops my mpg from 17-20 to 11-15mpg during the winter.

 

[jeremysdad]

I don't know where U live but here in the NE winter blended fuel drops my mpg from 17-20 to 11-15mpg during the winter.

Agreed. Also, starting your truck to let it 'warm up' decreases fuel mileage.

 

[hank857]

He is in AZ, look for a dragging brake or brakes on the truck. It doesn't take much to slow one down. Caliper could be stuck up front, rear shoes dragging?
Also make sure that emerg brake is fully released.

Have changed anything like tire sizes?

You are in east LA so you may be getting gas from over that way and it is pretty sorry stuff to begin with!

 

[Andy D]

Do you smell any burnt stuff. Hot brakes are gross smelling. Are the hubs warm? OK? Smells and heat are bad. Also check ignition for weak spark. And the coolant temp sensor for the ecu.

 

[Nhaz]

I don't know where U live but here in the NE winter blended fuel drops my mpg from 17-20 to 11-15mpg during the winter.

Not to mention added air density from being cold. makes it harder for the engine to push the truck through the air.