Gas consumption

[RageRover]

SeaFoam works wonders when I use it in the gas tank, or through engine manifold vacuum. I have not tried the step where you would put the product in the crankcase as a flush or whatever, but it has made some improvements. A guy at school I was talking to earlier ago, said after going through a half a can of the stuff through manifold vacuum, his overall vacuum from the motor made an increase in Hg/In. (inches of mercury). Seems to do what it is meant to do I say.

[ObraViva]

I'm doing on my RRC 91 (168K miles) about 285 miles per tank with regular gas. About 14 city miles a gallon.

[roverthen]

OK, so after a few tanks I calculated between 11.6 to 13.4 mpg. Not bad after all. I do get a lot better milage from the D2, even though it has bigger tires.

[Cris_RRC]

I just finish fixing the injectors I was getting about 8mpg with 2 bad injectors lets see now .

[skucera]

On our last road trip we got 17.2 mpg. That was 90% highway driving with the cruise set for 70 mph. Since that was right about at the EPA highway mileage estimate for an '89, and that average is known to be slightly optimistic for most cars, I figured we were getting about as good as we could expect. This truck has the aerodynamics of a tool shed on wheels, after all.

Also, I'd just put in new oxygen sensors, and the EFI light was out for the first time in months. Before, with the old O2 sensors, we were getting about 14 mpg in mixed city and highway driving.

Scott

[Cris_RRC]

Originally Posted by skucera

Also, I'd just put in new oxygen sensors, Before, with the old O2 sensors, we were getting about 14 mpg in mixed city and highway driving.

Scott

How is the O2 sensors affect your MPG?....not being a smart ass I truly want to know

[roverandom]

O2 sensors are a input to the EFI system. In a nut shell they tell the engine ECU how much ( or how little ) O2 is in the exhaust gas. If this is out of spec the system will try to adapt by adding/cutting back on fuel to bring it back to the correct level. So, if the O2 sensor is giving the ECU a faulty reading it will screw the whole system up. In most veh a O2 sensor is a wear item and has a set service life. just like brakes and spark plugs. Hope this answers your question.

[Cris_RRC]

Originally Posted by roverandom

O2 sensors are a input to the EFI system. In a nut shell they tell the engine ECU how much ( or how little ) O2 is in the exhaust gas. If this is out of spec the system will try to adapt by adding/cutting back on fuel to bring it back to the correct level. So, if the O2 sensor is giving the ECU a faulty reading it will screw the whole system up. In most veh a O2 sensor is a wear item and has a set service life. just like brakes and spark plugs. Hope this answers your question.

Thanks for the info ...in my case the O2 sensor is not clicking plugs in but it could get loose with vibration..any way of knowing if the o2 sensor is not working the way it should??

[roverandom]

Without boring you ( or myself ) with alot of techno mumbo jumbo you can boil it down to two types of O2 sensor. Not sure what Land Rover employs so I will give you the low down on both. One, a zirconium dioxide element, (Land Rover I think) compares the O2 in the exhaust with the O2 in the outside air. As the amount of unburned O2 in the exhaust increases the voltage signal drops off. Sensor ranges from 0.1 v (lean) to 0.9 v (rich) with a ideal mixture of 14.7 to 1 being 0.5 v. This reading (when veh is at operating temp) will change all the time but it should stay within the 0.5 v area if working correcly. Bad O2 sensors most always read low. Some of these sensors are heated to increase idle and start up emissions. A second type acts like a variable resistor, altering a base voltage supplied by the ECU. When the air/fuel mixture is rich, the sensor resistance is low. when air/fuel is lean the resistance is increases. The normal life span of a O2 sensor is 30.000 to 50.000 miles. Sensors can fail prematurely if they become clogged with carbon or solvents from non O2 sensor friendly RTV sillicone sealers etc. Older O2 sensor can become lazy and shows up as a loss of power, rough idle, poor fuel ecomy or increased emissions. the O2 sensor lives in a pretty nasty place on your veh so loose connections and /or corosion can be a regular problem. Readings can also be upset by a misfiring spark plug and air leaks in the intake or exhuast manifolds. Hope this clears the murky water for you. As for me, I think I may have to go and have a lie down now.

[skucera]

Yep, Roverandom tells it like it is. Oxygen sensors grow less sensitive over time, and rarely last more than 60,000 miles. The older 1-wire oxygen sensors lasted only 15,000 or so, but our Rovers are far newer and use very standard 3-wire heated O2 sensors... well, standard except for its odd size. Instead of using the standard size that uses the same size socket to remove as a spark plug, it is a much smaller size used by Nissan V-6 pickups and 300ZX sports cars. There are several FAQ's on the web with the interchange numbers. We bought our Nissan oxygen sensors at NAPA for about $65 each. It is a big savings, but that comes at the expense of having the wrong electrical plug on the end. You have to cut that plug off and splice on the old plug from your old oxygen sensor.

As I wrote, our Rover's freeway mileage went from about 14 mpg to just over 17 mpg. That sort of an increase is typical for the old cars I've bought over the last five years when I replace the O2 sensors. The biggest increase I got was from our trusty old Tercel 4WD wagon, which went from 24 mpg on the highway to 35. The Taurus and the Saab I got as commuters three years ago and two years ago each went up about 10% with new sensors.

Scott

[Cris_RRC]

Originally Posted by roverandom

Readings can also be upset by a misfiring spark plug and air leaks in the intake or exhuast manifolds. Hope this clears the murky water for you. As for me, I think I may have to go and have a lie down now.

I had all this ,the RR misfire due to 2 bad injectors (just fix over the weekend) plugs were change saturday (champion double platinum) only thing missing will be the exhaust manifold gasket due this week. Thanks for all the info ,any good web site to buy the O2 sensor from ??

[Cris_RRC]

Originally Posted by skucera

We bought our Nissan oxygen sensors at NAPA for about $65 each.
Scott

What Nissan model?? Thanks , that's nice 3mpg on a full tank is about a extra 60 miles

[Thor]

Just did a 'tank in a day' trip to Kelly Flats, west of Ft. Colins, CO.

275 mi/19.75 gal = 13.92ish

4 hours of highway and canyon road, 6 hours off road.

I could have done better by not caravaning with speed demons 80 mph +/- 10 mph. I also had my spare up top to see if it made the rig too top heavy on the trail, so aerodynamically I could have been better.

FYI

Picture by my man Jerome!

I'll try a new post to show what happened next in the off road or Range Rover section.

[roverthen]

Originally Posted by Thor

Just did a 'tank in a day' trip to Kelly Flats, west of Ft. Colins, CO.

275 mi/19.75 gal = 13.92ish

4 hours of highway and canyon road, 6 hours off road.

I could have done better by not caravaning with speed demons 80 mph +/- 10 mph. I also had my spare up top to see if it made the rig too top heavy on the trail, so aerodynamically I could have been better.

FYI

Picture by my man Jerome!

I'll try a new post to show what happened next in the off road or Range Rover section.

Great shot man!!!

[Cris_RRC]

Thor nice pic ,love Colorado ....what suspencion and tire set up do you have??