Hi all,
I just purchased a rover that is in ok condition, it is a 1990 Range Rover Classic county edition. This is my first rover and i got it for a steal. I am currently replacing all the fuel lines, because of some minor cracks, plugs, air, fuel and oil filters. My goal is to squeeze the best MPG out of this baby. I work for a parts store here in Nebraska, so price is not the problem.

I was first wondering if anyone who has experience with the 1990 RRC has tried the Bosch Platinum 4 plugs and if they are very effective for improving MPG, in the vehicle as of now are just some generic piles of crap.

Also have on order at the moment a K&N air filter and will be putting that in on sunday. The housing for the air filter is stock and I was also wondering if anyone has ever modified the stock housing? just some ideas.

Any help, ideas, and input would be greatly appreciated! I have limited experience with Land Rover but am very willing to learn and to make this vehicle run at optimum performance!

 

also what brand of oil would you recommend?
THanks again

 

If she doesn't leak too bad, I would use a synthetic 10w-40 (check your oil viscosity chart for the recommended range). I use mobil 1 on all my cars. My santa fe will tick if I use anything else. The rover doesn't seem to mind a whole lot, but it still gets the good stuff. There are many other great oil brands, like royal purple, shell rotella, etc. Go with an oil that has a good reputation is really what it boils down to.

I use the stock champion plugs because that is what the manual calls for. I bought a generic set of leads, that were supposedly made custom for the RR. Its been a couple years now and they seem to work fine. I don't think you could go wrong with the bosch platinums and magnecore wires though. If I wasn't so cheap, I would probably have used the bosch ones.

If you want great fuel economy, I would replace or at least clean your fuel injectors. They are very expensive to replace though. I would clean your MAF sensor too. Do a seafoam engine flush. I would definitely replace the air and fuel filters, but be careful with the k&n air filters. I've heard the rover MAF sensors don't like them and will eventually fail. There have been others on here that have had good luck with them though. As for me, I just assume not risk a $250 sensor to get a 1mpg increase. I've seen and heard of people modifying the filter housing, don't know if it made a difference.

For the best fuel economy, use the best fuel . Idle as little as possible (my rover would get 22mpg if it didn't have to idle). Coast to stops as long as possible, but don't **** off the person behind you though lol. When coasting the EFI is off and the transmission is turning the engine, so no fuel is being used. Once the engine approaches a certain RPM/Speed (the car knows its stopping) the injectors will reengage and start using fuel again. If you do it right and do not gun it, you should expect to reasonably get 15 to 16mpg. However, they do much better on road trips. Mine has been as good as 21mpg on one of my trips.

 

You WILL see lower MPG's by using 89 or lower gas.. 91 to 93 is the way to go. The price diff over a year negligable.

Champion plugs... The bosch 4's require a stronger coil in order to gain any useful spark advantage.

I could take or leave this whole SeaFoam craze in relation to the induction cleaning... There is quite simply zero substitute for removing the plenum and physically cleaning everything by hand. A little bit of alcohol vapor (seafoam) for a minute at most will do very little to clean up your air intake system from all the PCV residue. I do see the value in flushing a can through the fuel tank once in a while...

A complete tune up of the engine is the best way to see better mpg's and smoother running. Cap, rotor, plugs, wires, hoses and a clean intake.

Some people have luck with the K&N's... I have found the oem paper filter is best. If you leave any additional oil residue on the filter when servicing it some of it can get through to the hot wire sensor in the MAF and cause errant readings. Plus the K&N's allow greater air flow which = less filtration ability... if you are planning on running in a sandy or dusty environment then the stock paper is obviously the better choice for filtration vs. "performance" through increased air flow.

And on a slightly sarcastic note... if you feel you know more about engineering and design than the folks who designed your Rover then by all means, go ahead and alter / modify that intake system. They had only put 42 years of design and testing into it at that point.

 

Better MPG is the Holy Grail of the Rover world. If you find the answer you will be a rich, rich man. Many have gone before you and all have failed. The only way I have found to cut my fuel bill is to not drive it. These things are tanks and they get the gas mileage of a tank. If you bought it to be economical you bought the wrong vehicle. Actually, one of my favorite things to do is blow by ever Prius I see as fast as I can so that they choke on my spent hydrocarbons.

 

But seriously, the best thing you can do is just keep up on maintenance. Even just checking your tire pressure can do wonders. There is no magic device that will give you 20% better mileage, it there was they would have been factory installed.

 

all the tune up steps in the world may only yield 1 mpg.. be happy with 12 - 14 mpg, At 15 mpg you must be driving downhill everywhere you go... in an M.C. Escher kind of way.

My LWB weighs 4800 lbs before I even sit in it!



*Scott---Also I just noticed something you wrote ..... "When coasting the EFI is off and the transmission is turning the engine, so no fuel is being used. Once the engine approaches a certain RPM/Speed (the car knows its stopping) the injectors will reengage and start using fuel again"...

Who on Earth told you all that? Quite simply not true. The TPS and VSS work in conjunction to signal the ECM as to the state of motion and throttle position of the vehicle. VSS is directly responsible for controlling the IACV once the VSS senses there is no movement at the transfer case. The TPS tells the ECM what position the throttle is in and thus lengthens or shortens the injector pulse width (through grounding) to manage air:fuel mix. the only time there is NO fuel is when the car is shut off.

Now there's a good way to increase your fuel economy!! Shut it down when you are coming to a stop!

 

Ok, Ill keep all of this in mind. I really appreciate the help! I figured i wouldnt be able reap more than 2-3 mpg after every technique known to mankind, but I am willing to do what i can. at least until someone comes around and offers to buy this machine.

How much would a higher octane unleaded help? any ideas?

 

Or even adding an octane boost?

 

Popular Mechanics Did

When cars that have EFI are coasting, the injector pulse is zero. Meaning, no fuel is being used. Please read the 7th paragraph. BTW, I said the EFI was "off" to put it in layman terms. Its all still functioning, just no fuel.
Coasting in Neutral or Gear to Save Gas - Coasting and Fuel Economy - Popular Mechanics