Awful Gas Mileage

[newprot5fan]

WTF???? My last two tanks I have gotten 20 MPG?!?!!? It's not an SUV!!! It is mostly city driving with winter tires on, but still - the tires are inflated to 32 psi.

This is just stupid! Anyone else experiencing this? If so, what can I do? The air filter looks good and honest to god, I don't drive hard. I can probably count on one hand the number of times I rev the engine past 3300rpm.

Is there something serisouly wrong with my car?

 

[ho bag]

Maybe you need to give it a good beating. If you never rev it past 3300rpm maybe its gotten carboned up a bit.

 

[sirbeauris]

Yeah...The same thing has been happening with my protoge5.....I checked the last 3 times and I have only been getting 20-23 mpg....Something has to be wrong but I am not sure what...I'm taking it for an overall tune-up this weekend. Hopefully that will help.

 

[P-Funk!]

^werd. I get 30 (or better) MPG regularly...

..and i drive it like i stole it!

 

[Tom03es]

automatic or manual transmission? It seems the auto transmission are gas hogs while the manuals can sip on the gas.

I get 22-24 in automatic mode and 24-26 in manumatic mode.

 

[newprot5fan]

^werd. I get 30 (or better) MPG regularly...

..and i drive it like i stole it!

How is that humanly possible???? Even on the highway, the best I ever got was 30mpg (and that is going 120km/hr)

I'm relatively new to figuring out how cars tick, so what else could affect gas mileage other than tire pressure, the air filter and hard driving?

I just had my EGR replaced (for free) so that is taken care of...

Spark plugs??? Does that make a difference? I got it used from a dealer but they didn;t replace the plugs (the car is a 2002 with 54,000km on it when I bought it)

Any suggestions?

 

[mogi]

new plugs wouldn't hurt, get the stock NGK replacements and make sure they are gapped properly (0.040 to 0.044), don't trust pre-gapped plugs to be correct

also, with the new EGR, you might want to reset the ECU, disconnect your battery and pump your brakes a few times, let it sit for about 5 minutes, then reconnect. It will take a bit for the computer to re-learn, but you might end up with better mileage out of the deal

oh yeah, and depending on where you live, winter blend gas can hurt your mileage

 

[BOOSTR]

Put a few more psi of air in the tires. Definitley change the plugs, pcv and air filter. Not sure on the km to miles conversion, but you may want to change to coil packs and or wires as well.

 

[njaremka]

automatic or manual transmission? It seems the auto transmission are gas hogs while the manuals can sip on the gas.

I get 22-24 in automatic mode and 24-26 in manumatic mode.

what he said - need to know if you have an auto or manual.

the auto cars average inthe low 20's, manual cars average around 30.

 

[mogi]

he shouldn't need new coil packs or wires, that seems like a waste of money

 

[pasadena_commut]

the auto cars average inthe low 20's, manual cars average around 30.

Well, the automatics give poor mileage but really only in city driving. In the city the autos sucketh greatly and turn in mpg figures in the low 20s, whereas the manuals are reported to give at least 5 mpg more. On the highway both types do around 30 mpg. There's too much variation in tires, driving habits, and gas composition to generalize much more than that.

 

[P-Funk!]

How is that humanly possible???? Even on the highway, the best I ever got was 30mpg (and that is going 120km/hr)

[snip]

As you look at my mods (except for wider tires which cause more friction and the weight of the stereo) they each yield some side benefit in improved gas mileage - or at least don't hurt it). I measure by always filling the tank ('pushing' some more gas than the first 'stop' to make sure it is full) and resetting the odometer. I then do the math on the next fill up. I still coast to a stop when practical and i don't tailgate (speed up slow downspeed up slow downspeed up slow down).

 

[16902]

not to mention that most trucks that are EPA rated for 15/20 (city/highway) actually get around 10mpg or lower in the city.

 

[16902]

As you look at my mods (except for wider tires which cause more friction and the weight of the stereo) they each yield some side benefit in improved gas mileage - or at least don't hurt it). I measure by always filling the tank ('pushing' some more gas than the first 'stop' to make sure it is full) and resetting the odometer. I then do the math on the next fill up. I still coast to a stop when practical and i don't tailgate (speed up slow downspeed up slow downspeed up slow down).

you will actually get worse mileage by "topping off" your gas tank. it is the way cars are designed now that they burn off the fuel vapors in the tank as well to increase the mileage. i don't really understand how it works that well, but it is something to that effect. someone else will know for sure

 

[fonzinator]

Cheap things to try first:

1. Replace Spark Plugs. This is really inexpensive (NGK V-Power about $2 each) and you can do it yourself. If you don't know how, find someone in your area to show you.

2. Check/Replace air filter. DIY for sure.

3. Switch to 5W30 oil for the winter if you are in a cold climate. The lower viscosity may improve fuel mileage.

4. More PSI in the tires.

5. Replace fuel filter.

 

[thrasher]

Cheap things to try first:

1. Replace Spark Plugs. This is really inexpensive (NGK V-Power about $2 each) and you can do it yourself. If you don't know how, find someone in your area to show you.

2. Check/Replace air filter. DIY for sure.

3. Switch to 5W30 oil for the winter if you are in a cold climate. The lower viscosity may improve fuel mileage.

4. More PSI in the tires.

5. Replace fuel filter.

for #5. the sock in the tank? or is there another?

 

[ctt 1982]

cold weather has a big effect on mpg

 

[fonzinator]

for #5. the sock in the tank? or is there another?

Our P5s don't have an inline fuel filter? Perhaps they don't...I've never seen or replaced mine.

 

[ho bag]

I believe its only the sock in the tank. I always wondered why they never had a real filter, Although its easy enuf to add one in the engine bay if u want

 

[B1GHAM]

I believe its only the sock in the tank. I always wondered why they never had a real filter, Although its easy enuf to add one in the engine bay if u want

the only fuel filter in the proteges is INSIDE the gastank. There is no inline filter.

one thing only 1 person has touched on is winter blend gas. Winter blended gas will usually yeild slightly lower gas mileage, although it should only be about 2 mpg at best. Where do you live? this might help us figure out other issues.

Also, cars do like to "breathe" everyonce in a while. Try going out after the car is warmed up and really romping on it for a few minutes. Doing so will help blow carbon deposits from the cylinder walls and exhaust system. Yes its fine to ride around shifting @ 3300 rpm however you will lose some performance/gas mileage due to deposits of carbom.