Hey guys. I am new to this forum but I know these places area great source of information frompeople in the know. I was hoping you could help me with my 99 Discovery 98k. I call her Martha she has been a good ride but is a bit of a hag. I am facing a decision of having to sell her or get some better gas milage. She is getting about 10 City and 15 Hwy. Overall she has been pretty good to me, although I have cursed her quite a bit. I do not want to sell her and get some little car. I have about $500 I am willing to spend on improvements and repairs. But I have to get her up to 20 Hwy miles a gallon. What would you suggest for improvements and repairs that would be the most cost effective within my budget? Thanks.

 

Won't hit 20 on the road with her.
I have a heavily modified 99 and am happy at 16MPG in Colorado at 6000 feet.
The best mileage I have seen or heard runs 17 to 18 for the most part.
Things that are against you are the weight of the vehicle, Old O2 sensors, possible drop in compression based on mileage, possible tune issues.
What octane gas are you running, what size tires?
By the way mine has been named Mona by my kids.
Mike

 

Thanks for the quick info mike. I am have been using the search here and realized I am about to get burned for my stupid question. I really just don't want to sell her. I probally don't even get 15 Hwy. I am hust looking for alternatives that will justfy me keeping her. She is pretty much stock besides some tight tint. I got 29.0" GY P235/70R16 and never keep them at the right pressure.I alwasy run 87 in her.I know I could use a new air filter and spark plugs any suggestions? I am not looking for snake oil I just drive about 60 miles to a neighboring city about 3 round trips a week and I am getting killed. I have had her for a long time and always known she has been bad on gas but times are tough.

 

87 octane can cost you 2 MPG by it self much less the tune item.
Mike

 

With all respect (read LOL), I drove from Chicago to Brainerd , Mn. last summer in my '97 D1 se7.
It was approx 22hrs round trip.
60-80 deg. Outside
65 mph on cruise (rare)
93 octane
cleaned maf (but don't tell mike)
2 new front O2's
Firestone destination le's 235/70/16's 30&40 psi
85k on odom
No extra crap in car
=20.4 mpg

 

Premium all the way. run the highest you can get. You are looking at $4 more a tank, but it will save you $$$ on MPG. and like Mike said.... the tune issue. Replacing the O2 sensors will get you a little more, but that will be a few bucks. New plugs with a set of new Magnacor wires will help it fire better, and it isn't too expensive to change. I am getting high flow cats next week and will be tracking my mileage just to see. Watch out for the K & N air filters. They can kill your MAF.

I drove to Chicago, CEL on, 17.8 average. I run full synthetics in the driveline, and had just changed them. CEL is off now, got a new fuel filter, but haven't been on a good trip to check mileage. Has to be better cause in town is now 16.3 average. A good tune up, good alingment, and good tires will help. Get premium fuel in it ASAP. You can Seafoam the intake, that helped me a lot, and add it to the tank.

Having said that, Disco's get poop mileage.[&o]not a whole lot you can do...Good Luck!

 

I just drove to Texas from San Diego and averaged 17.3mpg on the highway. This is with a 3+" lift, 265/75R16 Goodyear Wrangler MT/Rs, aftermarket steel front and rear bumpers, rock sliders, underbody protection, hella 4000's on the front and the back loaded with gear (tools, bike, clothes, and a bed platform/mattress). The biggest jump I noticed in mileage was after changing my plugs and wires at 55k miles. Put in Magnecor 8mm wires w/ Bosche Plat +4 plugs and went from ~11.5 mpg -> 17.3 mpg. My previous jump was from ~9.5 -> 11.5 after changing to a K&N air filter from the old disgustingly dirty paper (it works great, my MAF is fine).

I don't think it would be out of this world to think that if I changed to street tires or A/Ts and dropped off my hundreds of extra pounds of accessories which are seriously hampering the Disco's already terrible aerodynamics that I could get upwards of 19/20 mpg.

 

Thanks Mike, Greg and Ok. I officially now hate this site.[:@] After doing a little searching I realized how bad I have miss treated Martha and I am going to do some serious work on her this weekend. She is in worse shap than I let on. Her service engine light is on, rear windows will not roll up or down, headliner is saging and overall she looks pretty bad. I am going to go run tommorrow and get the fault numbers. I got a big couple of weekends planed and will probally be on this site a lot and I appreciatte all your help. I am going to need some window regulators and 02 sensors. I am also going to be looking for air filters, plugs, etc. I am also going to put a full detail on her including leather, scratch, trim, and wheels. If I can not get her up to where I need her to be with the gas milage I want to at least send Martha off looking her best. I am going to shoot for 18 MPG and if I can hit that I am going to keep her. Thanks for all your help here. I will try and get you guys some before pics tommorrow and I am sure I will have plenty of questions.

 

If you are wanting to do alot of the work your self, send me you tele number and a good time to call, I would be glad to walk you thru fixing her up.
Mike
mikeljacobs@comcast.net