Very Poor Gas Mileage

[Iowa4Runner]

Ok guys, lets get back to the topic an that is Pinuz's gas mileage.

Getting annoying are we? Hitman is starting to talk in circles, and has opened a new can of worms in his most recent response. I've got counter points to everything he's said, but I get the feeling it won't benefit anyone to drag this out for another 50 posts. Besides that, I've got stuff to do. Hitman- you can have the last word...

 

[DaveS]

Short trips in cold weather are probably enough to cause the mileage you are getting imho. Ever tried filling up, resetting the mileage meter then starting the engine ? - the mpg reading is frightening at first because the V8 takes a lot of gas to start it - running on choke in cold conditions will only add to this.

My V8 idles at around 5-600rpm in neutral but idles at 1000rpm on choke after the initial 1200-1300 start up rpms. It takes quite a while to warm up (I am putting that down to the size of the chunk of metal that needs to heat up)- especially if I start off in a low speed limit area.

The short runs you are talking about will result in poor mileage and more concerningly fairly hard wear and tear on the engine and drivetrain. You should probably follow the service schedule for heavy wear conditions if you are not already...

 

[Pinuz]

Does your 4R actually reach operating temp when you drive. I was thinking about it. It may just be the fact that you drive short distances in cold weather and the FI will compensate by making the mixture richer. I would say maybe drive a couple of miles extra once or twice a week, to make sure the engine heats up properly.

Also for general longlivety I would say hit a good few miles of highway at least once a week. It is not good for an engine just to be used for short distances, especially in the cold. Your engine oil will get a lot more moisture in and you engine will build up carbon from constantly running at low rpm with a rich mixture.

Just take it out for a spirited highway drive every week, and do a few miles extra to make sure it heats up properly a few times a week.

Does the temp gauge get to halfway when you do your daily trips for at least half the trip?

-----------------------------
thank you bulldog-yota for your help, I think you're right.

Unfortunatlly I'm driving everyday less than 10km, yesterday I refill the tank and the Kms are 250 (156 miles) and the litres 57.9 (15.3 gallons), little more than 10 mpg and little less than 4.3 kms per litre!

The themp is ok on the centre, the choke stops just when I arrive at work in the morning (no traffic) 5 minutes, in the afternoon the same 4.5 kms trip takes over 20 minutes.

The RPM in this trip are high (of course) 1200-1400 in the morning and 800 +/- in the afternoon

I should go more in the highway....but I want to have the car serviced for a check since my Grand Cherokee in this condition was better.

 

[DaveS]

I'm not sure where you are in Canada but you might want to get a block heater if you dont have one already - this should reduce the time it takes to warm the engine up at this time of year (and help reduce wear)

I am getting one fitted today and plan to monitor my gas mileage to see if this pays for itself in fuel savings at this time of year in fact. (I live out in the country and its freqently below -20c at this time of year)

 

[LukeSKY]

I have the 2005....v6


I get 400 miles per fill-up..

0
400
800
1200
1600 5th time.....filling up this weekend

 

[Pinuz]

Thanks Daves
I live in Vancouver, BC and here is quiet warm.

Please let me know about your mileage and the road you run (HIghway mixed etc etc)

I'm not sure where you are in Canada but you might want to get a block heater if you dont have one already - this should reduce the time it takes to warm the engine up at this time of year (and help reduce wear)

I am getting one fitted today and plan to monitor my gas mileage to see if this pays for itself in fuel savings at this time of year in fact. (I live out in the country and its freqently below -20c at this time of year)

 

[live4swell]

I have the 2005....v6


I get 400 miles per fill-up..

0
400
800
1200
1600 5th time.....filling up this weekend

That must be nice, i get just under 300 miles per fill-up with my '03 V8, i just chalk it up as a loss...oh well

 

[pbm317]

My 03 V8 has been getting some pretty crappy mileage lately too. I get like 16 highway... maybe I'm driving too fast?? hahah

 

[Cleric]

filling up at E is hard on your fuel pump, because it is located inside your fuel tank and is cooled by being submerged in fuel. If you run your tank to E often, you may be shortening the life of your fuel pump.

This is true. If you regularly run your tanks below 1/4, you may overheat your fuel pump. It can also be bad in the winter if your tank is filled with air (because of the water). I was taught in my auto tech classes to keep it above 1/2 and I still do.

 

[Expat]

This is true. If you regularly run your tanks below 1/4, you may overheat your fuel pump. It can also be bad in the winter if your tank is filled with air (because of the water). I was taught in my auto tech classes to keep it above 1/2 and I still do.

I'm curious on these points you and others have made on this subject. I did a quick search on the net to see if there was any validation to your comments. I was unsuccessful. Have you got any specific proof (err... research/reports) that supports this? If so, could you direct me to these?

Thanks
Mark

 

[Cleric]

Have you got any specific proof (err... research/reports) that supports this? If so, could you direct me to these?

I was taught this in an Auto Tech course. I have also seen others mention it in this and other forums, but do not have any literature to cite. It seems like I remember reading about it in the "Auto Q&A" section of my newspaper a few years back, but really can't remember for sure.

 

[iFORCE]

I can run 12.5L/100KM but sometimes I have some fun so it'll go up (14.5L/100KM). What is that converted to MPG?

 

[live4swell]

My 03 V8 has been getting some pretty crappy mileage lately too. I get like 16 highway... maybe I'm driving too fast?? hahah

I have a mix of highway / city and I get 13-14 mpg, its pretty bad in my opinion. It has seemed worse this winter.

 

[CuzzinOlaf]

It has seemed worse this winter.

I was just thinking the same thing... Does gas mileage get worse in the winter?

 

[LukeSKY]

If you regularly run your tanks below 1/4, you may overheat your fuel pump.
-----------------------------

That is what the factory warranty is for!!!

 

[DaveS]

I was just thinking the same thing... Does gas mileage get worse in the winter?

Yes - a lot worse - primarily because of the extra time for the engine to warm up.

 

[Koz]

Some things to do to get better gas mileage.

Avoid excessive acceleration (tough one for me)
Avoid long warm-ups
Avoid using A/C when running the heat (use only to defrost)
Remove unnecessary weight
Use all synthetic fluids and grease
Keep tire pressure on the high end of recommended range
Use cruise control as much as possible
Keep air filter clean and car tuned
If you don't go off-road get good street tires

I have a supercharged Taco and I get anywhere from 12 to 21 mpg depending on my right foot. The Taco weighs 1K pounds less then the 4Runner, so the mileage on the 4Runner is pretty good, considering. The 4Runner, like most Toyotas, get some of the best gas mileage in their vehicle classes. If you’re upset with the gas mileage, you should have thought about that before buying this type of vehicle. Me personally, it’s worth every extra dollar of fuel, to have such a GREAT vehicle.

Koz

 

[BigDogMoney]

It's pretty darn cold up here, but I only warm up the car for a few minutes (3-4 minutes). I'm not like some that turn on their cars and immediately drive away. If I'm in a hurry I'll drive slow and avoid hamering the gas until the car is at operating tempature. I think it's important for the oil to properly warm up and lubricate those hard to reach components of your engine. Regarding the gas mileage - yeah it's pretty bad in the winter. In the summer I consistently get over 400 miles to the tankful, but now I'm probably at 360 to 375.

 

[linhsy]

My 4Runner used to get 390/tank. Now in the winter time, it only get 370/tank. Normally, it takes me a week to fill up the gas tank again, but now it takes 3-4 days. Gas price is also go up at my place $2.10/gallon.

However, it is all paid off. Yesterday, I was stuck in the parking lot with quite some snow. There is a truck in front of me so I can't go forward. I was still in 2WD mode and it slipped while I was trying to back up. Then, I engage to 4WD and have differential locked. It backed up with ease. I'm happy.:rocker:

 

[Hitman]

I'm curious on these points you and others have made on this subject. I did a quick search on the net to see if there was any validation to your comments. I was unsuccessful. Have you got any specific proof (err... research/reports) that supports this? If so, could you direct me to these?

Thanks
Mark

This discussion came up a few weeks ago here.... and it turned into a big can of worms.

It's a well-known fact (by auto techs at least) that the electric fuel pump, which sits inside the fuel tank, is cooled by being submerged in gasoline. If you keep your fuel tank level low on a consistent basis, there's a good chance that you'll shorten the life of your fuel pump. Here is a quote/link for you:


Electric fuel pumps are almost always located inside the gas tank. This helps prevent vapor lock and keeps the fuel pump cool. The pump is a turbine type hydraulic unit directly coupled to a permanent magnet motor. Fuel is used as a lubricant and coolant for the motor.

From: http://autorepair.about.com/cs/doityourself/a/aa050701a.htm