Hello all,

first, can't find the O2 sensor on my '94 disco. It's from Namibia. Isit possible Discos in Africa from that era didn't have a O2 sensor?

Two operating problems: one, the engine cuts out abruptly for a few seconds and then returns to normal operation.

Two, the engine has an intermittant idle problem; idle is erratic and engine dies.

Don't know if the issues are related.

It's a manual and has a new fuel pump and fuel and air filters.

Thanks,

Tim

 

Idle air control valve (IACV or stepper) may need cleaning, you remove it from the mount and use spray carb cleaner, don't move the tip yourself. Also clean bore it comes out of. Fuel pump issues? Ignition amplifier issues? There were O2s on the Lucas systems used in 94, see https://landroverforums.com/forum/at...ionsystems-pdf

 

No O2's on non NAS trucks, no catalytic converters either.

I am assuming this is a petrol engine, if it is the petrol V8 then the engine cutting out while driving for a brief moment and then coming right back is a bad throttle position sensor.
The bad idle is probably a bad idle air control valve, but I'd replace the TPS first.

 

Thanks, I'll clean the valve and bore and see how that works for the intermittent idle issue.

New fuel pump and filter. Sorry, should have mentioned that.

Appreciate the advice.

 

Yep, doesn't have a CAT either. Is NAS a designator for African export vehicles?

Yes, petrol, (gas), engine. Sorry, should have mentioned that. Will order a TPS and have someone bring it back from leave.

I'll try and clean the idle air valve first and then replace if that doesn't work.

May I ask; without an O2 sensor is the FI system just an open loop type since there is no O2 sensor for feedback? Why develop a different FI system for export? Less expensive?

My 94 has about 270K km but is doing a pretty good job here in Juba.

Thanks for the assistance.

 

NAS = North American Specification, GULF = Gulf States, UK = United Kingdom, Japan = Japan, ROW = Rest of World

The FI system uses another value (fixed I believe) instead of the O2 for information. But along the way Rover has put CATS baed on the individual county market, so the US not the only ones with this affliction. See Rover 14CUX Hot Wire Mass Flow EFI: Service and Troubleshooting

 

Thanks for the acronym list. The groups I work with use them to distraction.

The 94 disco I have is turning out to be an excellent vehicle here. The ride quality on the poorly maintained roads is far superior to anything in its class. I really must be getting old since ride quality became important.

During the rainy season the discos ability to move through mud has been outstanding. The independent front suspension and full time diff really shine.

Diesel is the preferred fuel here since gas, petrol, supplies can be limited at times, and the V8 drinks a lot of fuel, but besides the minor issues listed it seems a reliable motor.

One additional issue; that may not be worth addressing. There is higher speed gear whine that is related to vehicle speed and not gear choice, accel/decel or engine rpm.

Any obvious places I should look that are particular to this gen disco?

If I had to guess I'd say the sound is coming from the middle or front of the car; not the rear.

Top speed around Juba is probably 60 kph and only for a very short distance.

Thanks again,

Tim

 

Change oil in differentials and transfer case, many older ones in the States move up to a 85W140 weight oil and that helps noise a bit. The transfer case drain is a small bolt (delicate) and the fill spot is a 1/2 inch square drive like the diffs, partialy blocked by the emergency brake. You'll want to get the fill hole open before you dain it (if you can't get it open, and you just drained it, you're in a bad spot). There are also "swivels" to fill with oil or fine grease on the front wheels (CV joints).

The transfer case is a source of whine. If run low, and gear damaged, it is a large project to swap out.

 

Sounds very reasonable. A vehicle with this many miles probably needs it in any case; even if it doesn't help the whine.

Since you've been so kind and helpful to a soul in a primitive place perhaps I can ask about an additional item. When I bought the disco I swapped out the fuel pump, fuel filter, air filter and spark plugs. The old plugs seemed pretty black and might indicate a rich running condition.

Is there something that would be creating a mild rich condition?

Except for the abrupt cut out issue the motor seems to start and run pretty well overall.

I should say that the old air filter was very dirty and may alone have been enough to make the engine run rich.

Thanks,

Tim

 

Thanks Spike and Savana.

I put in a new idle control valve and a new TPS.

The TPS had a different plug but I just cut off the plugs and used the old one.

Disco runs without the stutter now and idles very well.

It's turning out to be a very good vehicle for South Sudan.

Thanks again