Just got my 98 disco last night, Very high mileage and thought it was in decent working order. At least the fluids are very clean, Geting a rover to 260k there must have been lots of fluid changes! LOL! I am having a little problem now.
1st It is idling around 1800 rpm. A friend of mine thinks it is the idle control valve. Could be I just don't know, I am coming from old vw's with carburetors! LOL?
2nd while getting to know my rover the Brakes lights are stuck on now. I was up till midnight playing with it and now my brain is in over drive and eyes sore from looking in the manual on a Iphone. Currently looking at the PDF version my work computer and need help getting to the right section to figure these things out.
Any help would be really appreciate, funny I am not a newbie in VW land but I am surely here. I can do it but will need some kind guiding gurus to help me start out. Looks like a good place to be here on the forum.
thanks
Erick Sowder
Greensboro, NC

 

IACV may need attention (remove, clean with carb cleaner, clean bore it fits in), if you have scanner any codes? Also, if coolant temp sensor is unplugged it will make ECU think it is -40 F. Or just a good old vacuum leak.

Brake light switch under dash is one place to look for the minor problem. See attached from RAVE electrical troubleshooting manual

 

Thanks Savannah, just what I needed to know. Is the IAVC mostly serviceable? We cleaned it but still had the same problem, Is there a way to check it out on its own? Ohms and such? Looks like they are not to expensive. Will check the coolant temp sensor also.
Still bugging me on the Brake Light issue. Does the Diff lock lever have anything to do with the brakes? Like a switch on it or something like that? Might be a day before I can get back over to where my Rover is, any info I can stick in my head will help me figure it out.
thanks again,
Erick

 

see revised post for drawings and pix. IACV should be examined before replaced, have it out, plugged in, turn on key and look for movement (it is a stepper motor). Resist temptation to "adjust" it. Replacement makes ECU have to re-learn it, some have problems getting that to sysnc just right. Me being one of them, I finally got a used ECU and IACV from donor vehicle. My ECU may have been bad to start with. The IACV is cheap and I believe may be crossed with some other vehicles.

 

Check your brake switch up under the dash to see if the switch is stuck.
Did you clean out the manifold opening where the IAC fits is? How about the t/body, they get quite dirty, clean it out with carb spray and a tooth brush if necessary. Might also check for a vacuum leak. Once that is resolved, might want to look in the sticky at the top of this section and read/do the major service list before doing any wheeling.

 

Great guys! I will let you know what I find out once I can get back too it. Glad it is a play toy and not a primary vehicle! LOL! We briefly checked the brake switch but it was getting late. I like the idea of checking the Iavc and seeing if it moves. Stuff like that is making me more cozy with this disco. Onward!
Erick

 

Not likely but it did happen to me so I'll throw it out there. When we got ours we noticed every now and then it would develop an irratic idle, sometimes jumping up to 1500 rpms. Fiddled around a bit and took my toe and pulled the gas pedal up, idle dropped. I was chasing the IACV, coolant temp sensor and a bunch of other crap when all I needed to do was fix the throttle cable and return spring.

 

Thanks for the suggestion Dustin, I have had the non returning pedal before in other cars.
I did fix the brake light problem yesterday. Apparently at first glance in the dark I felt the switch and it seemed good, but in light of day yesterday i see that there are 2 switches on my 98 and the upper one fell out of its holder. Put it back in and the brake lights work. Not happy about how the switch as it seems very likely it will fall out again.
Hopefully today I will get to the idle problem today. I drove it to the store yesterday right after I fixed the brake light and it is fun to drive and the visibility is intoxicating unlike all the new cars with tiny windows! Refreshing to actually see out! I sure hope new cars will trend to bigger windows like the defender some day. The new cars might as well cover up the windows all the way and put in cameras to see out, seems like the trend anyway.
later
Erick

 

The trend is to defend against side impacts........hence smaller windows, side curtain airbags and steel beams inside doors. Doubt it will change anytime soon. Dustin nailed one of the problems with these trucks that gets overlooked, adjusting the throttle cable slack and the return action. It's in the Rave. A variable reset of the ECU will usually fix it but in a pinch you can try the untech method. With ignition off, unplug IAC. Turn ignition on but don't start and plug in IAC, wait a couple of seconds then turn off. Do this three times. Sometimes that will do the trick.

 

IhScout, thanks for that tip! I will try that first this afternoon.
I must admit this is a refreshing site that is kind to new owners, I am reading all the time so hopefully some day I can help others! LOL!
On the topic of new cars yes the side impact is really causing the stir on smaller windows but still I don't like it. the new Acura almost have no rear side windows. Might have to keep the older cars for a long time. MY 66 vw bus has very good visibility just like a disco