Hello Everyone!

First post, hope someone can help. I just bought a 99 Disco form the north island of NZ and had it shipped down to the south island here. Well low and behold it has issues that were unstated by the seller. I have problems with a wandering idle after it has warmed up. (think it just requires cleaning of an idle air control valve, had the same problem on a ford years ago) but the biggest issues is when I going up a grade.

I will be cruising up a hill about 60 mph and need to shift down to 4th to keep speed. When I apply the clutch, shift into 4th, release clutch and depress acclerator there is a pause of roughly a second (little more) and than I get power. Also 4th or 5th gear (only ones ried so far) if I let of the gas completely and then press the gas again, there is the same pause before i get any power.

I have only had this problem while going up a grade, or just after going up a grade. If I'm in the flats for awhile it doesn't seem to do it.

It feels like the clutch has engaged, the rpms change when I let off the clutch, but i can't say for sure what they do (go up or down). I also notice a surging going downhill, I can let off the gas completely but the rig will still lurch/surge a bit when going downhill (only ever happened in 2nd or 3rd so far not more thatn 45mph) which i thought was odd, never had that happen before in a manual (unless you really pick a wrong gear, but this is not the case).

So I'm not sure if it's an issue with the clutch or with the maf/tps sensors....? I just got it yesterday and I'll take it for another spin and see if I can say what happens more in detail to the rpms when going up hill.

If anyone can give me any suggetions that would be great.

Thanks,

Peter in New Zealand

99 Disco 5 speed 3.9L (series I)

 

So doing some more driving last night, I think it is a clutch issue. It feels like it's sticking and not gettin engaged fully. The usually only happens when you've been driving uphill, but I have had it happen on normal flat ground. I never smell clutch burning, so I don't think it's slipping, I think it's just not engaged. Seems like the clutch is stuck in the disengage spot and then pops into after some gasis given. It's a pretty solid lurch when it does catch though, feels like i just dropped the clutch and not let it out gradually. Anyone have any ideas about this?

Also spark knock..... looks like it has a very new cap and rotor, plugs and wires, but there is some noticable spark knock. You can really tell when you are giving it 1/3 or more throttle (up hills again lol). Sounds like a timing or spark gap not being right, but I'm waiting for my container to clear quarintine to get my tools out, so can't really check right now. ButI assume that's what it is. Running 95 octane, so don't think that's the problem. Any ideas on the spark knock?

Thanks guys.

Pete

 

Ok so this knocks something out of the question.

I cleaned the throttle body and idle air unit today. I also made sure that all plugs were gapped properly and they were. Nothing to crazy from the plugs, look like a inner clyinder on each side burns a bit of oil. But not bad.

More about the hesitation. After I cleaned everything today and put in a new air filter (old one was pretty dirty) I did some more driving around town. The idle wandering seems to have improved.

A very interesting point is my hesitation and bad idle seems to happen in inclines....so I'm wondering where the fuel pickup is on a disco I? I am starting to think that there is water in the tank? I can't really seem to get it to hesitate except after going up hills and giving it 1/3+ throttle.

Interesting point 2is that I don't think it's clutch related. After running up the big hill and getting to the top letting off the gas and putting in the clutch, i change gears let out the clutch hit the gas and it hesitates and then goes. i put in the clutch and hit the gas, i can only get about 1500 rpms and it fumbles around 1500 clears and goes up from there. let off the gas again and push it again and get the same rpms climb to 1500 fumble and then clear and go up. can only get it to do it for a bit. at the top of the hill it's flat and once it's done that 3 times it goes away.

so i'm thinking spark knock up hills, and problems with going up hill is water in the gas??

Anyone else have any thoughts? Seems like it's not a clutch thing....so that opens a whole new can of worms. but not really being able to get it to do it on the flats makes me wonder.

thanks guys,

pete