I just purchased a 2000 Disco in Uganda. When I drove it around the traffic jammed streets of Kampala, everything seemed fine. But, when I took it out on the highway (after buying it), it drove like s#!t. The tachometer registered erratic changes, the gears kept changing and when I hit even the slightest uphill grade, the car slowed way down. At times, when I would reach say 100 km/hr, the car would start "lugging". Once in a while on the flats, when I had the accelerator pedal in just the right position it would run pretty good.

The guy I bought it from swears up and down that he has never experienced this and even just returned from a trip to Kenya without any problems. He thought maybe bad gas or clogged fuel injector. I will say that it starts right up without hesitation and idles very smoothly and appears to drive fine when traveling slowly over the dirt roads of northern Uganda.

Any ideas besides sticking to the dirt roads of northern Uganda?

 

Okay few questions,

Is there a check engine light?
Is the Disco diesel or petrol?
If petrol, what octane are you putting in? My only experience is South Africa which is 95.
Are there any other lights coming on in the dash?
When turning on the vehicle do the dash lights come on and go off as normal?

Edit: It sounds like you might have a bad fuel pump/filter (they are one unit in the back above the petrol tank).

 

If petrol, without any check engine light displayed (it should bulb test at initial crank up), or stored codes read (check out pix of the $70 US "Ultra Guage" code reader and data display) I would say that engine computer is being fooled by a sensor out of range. The engine computer and transmission computer talk to each other on a data buss, adjusting things for changing conditions.

I would start with checking the sensors to be sure all are plugged in firmly. Then I would check the air filter, all of the pathway from that to the engine to be sure all is secure, no leaks.

I would clean the MAF sensor IF and ONLY IF you can obtain a spray cleaner made for MAF sensors, and do this when the engine is cold, and you have NOT turned on the ignition at all. That sensor has an internal heating function, and a hot sensor does not respond well to a sudden blast of cold spray.

I would evaluate the throttle position sensor, and clean the actual throttle body with spray carb cleaner. The TPS tells the computer what angle the throttle butterfly is, so the computer can judge how much fuel to apply. Truck should run with sensor unplugged, using a default value. Check engine light may come on. Sensors have been known to go bad, they are a variable resistor. Using a scanner, they should show a smooth change in throttle angle when you step on gas pedal. This value goes from a minimum of maybe 9% up to maximum of say 96%. The idea that you have a "sweet spot" follows the idea that you could have a sensor that is erratic, like a noisy volume control on an old radio.

Pages attached from the "RAVE", the Rover issued shop and owner manual set. Full download for free in links below.

Note: Pix shows why you can't trust the factory heat gauge, it is either cold, 50%, or baked. Also as a new owner you should be aware of the factory front drive shaft that tears apart with almost no warning and pokes a big hole in transmission. Rebuild info to add grease fittings write up in our tech area.

 

how many miles on this truck, a stretched timing chain will give you a lot of those
symptoms.

 

Get your charging system tested, if voltage is below 13.6, there is your problem.

 

You have some very good advice here and have a great place to start. We do need more info as to any light illuminated on your dash?

I have had mass air flow sensors cause me these problems before more than once . Heed the warning about cleaning your mass air flow sensor use crc mass aid flow cleaner if any and do as stated above. I would start here and then move forward. Also maf can fail at anytime even from one stop to the next do its possible that the guy is not bs ing you he may never experienced this problem.

Fuel injectors rarely ever fail so that would be almost ruled out.
Failed Fuel pump usually will not allow you to start the truck so that does not seem to be the culprit here.

 

Appreciate all the feedback. To answer some of the questions, This is a petrol rig and there are no check engine or other lights. The whole array of lights shows upon ignition but nothing stays on. Relatively low mileage at 74,000 km. I don't know what the octane rating is here - it hasn't been listed on the pump so far and the attendants had no idea what I was talking about when I asked. I might be able to find it on the internet.

I'll give this advice to the local mechanic which will probably give him a big head start and save a lot of unnecessary chasing. Again, many thanks.

 

Give your mechanic the RAVE manual too.

To Download the RAVE Manual, follow this link land rover service factory manual RAVE download land rover resource, service manual, workshop factory manual, download, rave, vehicles including discovery, series, defender, range rover, freelander, LR3, Handbooks, Catalog, Catalogue, Land Rover Inte

 

Normally unleaded premium petrol/super unleaded is around 95/98 octane so if that is what you are putting in you should be fine on that front.

 

I would put dry gas into it.
You may just have bad gas.
Dry gas will take out the moisture..
You may just have a load of dry gas..

Are you from Uganda?
If not, you'll need to learn where to get trusted gasoline.

Uganda Online - Petrol Stations in Uganda

Over 30 Brands
Shell, Caltex, Gapco, Hass, Gaz, Kobil, are among the petrol stations operating in Uganda. Otherwise they are quite a number and some have no names and these tend to charge a lesser price but at your own risk. The Uganda National Bureau of Standards (UNBS) normally carries out inspection checks to find out which pumps pass its test and those that have passed the quality check, an approval sticker will be displayed.