The 3VIL-Disco

[3VILC]

Well after a messy divorce and not having a 4by for a few years I'm finally getting back into it again, so figured I might as well start a build thread for the few of us still lurking around on the forums

I'd decided I needed a 4by again so had been browsing around Trademe and Facebook for some time in search of something suitable. The brief was simple, something not too expensive that wasn't f***ed and would be somewhat usable without spending a fortune on mods first.
I came across a Disco 1 V8i facelift and after some reading seemed they were pretty capable out of the box aside from the usual Land Rover "quirks". They were asking 3k but lived in the middle of nowhere so noone had really been to look at it and they needed it gone, so after some discussion they offered it to me for 1500 and it was sold, rego current and only hadn't had a WoF since Feb so can't be too bad
Here it is pretty much as I got it, racing slick tyres 1 showing canvas, and absolutely filthy inside and out but I could tell under all the crud was a pretty good tidy wagon:

(Fingers crossed linking to google photos still works)

And so it begins..

I quickly found a set of well loved but still usuable 265/70R16s which just squeeze under at standard height although I imagine the will rub under flex:


Now since its a very budget build at the moment, I chose the 'cheap bastard' lift, rear springs in the front, and 80 series fronts in the rear, so i eventually found a pair of used cruiser springs for $50 which are sitting in the shed so more on that another day when I get them fitted

[Crawlerer79]

Great to see another Disco out there!

They sure are capable out of the box, and with a lift and those muddies, you'll be surprised where it'll take you!

Looking forward to this one!

[Cameron]

nice!
great rigs!

[aroma]

nice to see another basic build on here, just to remind us not all builds have to be big and mean to get us off the black stuff from time to time, then break every time you use them .. another landy sigh .....

[3VILC]

Work last weekend and work this weekend, but off the weekend after and the Mrs is away so I smell a shed weekend coming on haha.
Have managed to strip all the headlining and manually close the sunroofs. No more water seems to be getting in so hopefully can now put the interior back together and clean out all the filth inside lol. Had to strip all the soundproofing and throw some away and try dry the rest that stuff holds water lIke a mofo! Fortunately theres not a lot of rust in the floor so a bit of a clean up and prime should be fine

[1bad4x]

Nice trucks them Disco's & love budget builds, really gets the creative side alive Anyone with deep pockets can build or pay to have built a cool truck. but on a budget... totally different story...

[1bad4x]

BTW I would suggest replacing the expansion tank if it hasn't been done, heat, time & plastic... not a good combo. Mine blew lucky not out on trail..

[3VILC]

That looks fairly new, the previous owner spent a bucket load on the motor I think the workshop must've seen them coming I hate to think what the bills were compared to what they sold it for. While I don't have receipts most of it is fairly obviously new. New injectors new cam lifters (evidenced by the old ones found rolling round in the boot) new radiator new water pump

[1bad4x]

That looks fairly new, the previous owner spent a bucket load on the motor I think the workshop must've seen them coming I hate to think what the bills were compared to what they sold it for. While I don't have receipts most of it is fairly obviously new. New injectors new cam lifters (evidenced by the old ones found rolling round in the boot) new radiator new water pump

Nice to have all that new.. makes an even better buy!
I pity the poor buggers that have to take anything Euro to a shop, as they tend to get totally shafted. crazy thing is they are usually easier to work on compared to jappa's, parts if shop around can be cheaper as well, but some maybe most shops see the Euro badge & start adding 0's to the end of all their prices..

[3VILC]

No looking at the giant 4 core radiator I imagine that would've been an arm aNd or leg by itself. There's a few other bits too that I can't remember right now. It's actually pretty tidy under all the crap. Just need to make up a cable to get some readings off the ecu and work out why it's overfueling. Afm hasn't been replaced so a likely suspect someone seems to have fiddled with the mixture screw on the afm also so could be just way out of whack

[3VILC]

Well not very productive so far. Was planning on having a diagnostic cable made up to check the engine out, turns out as I suspected the cheap USB-serial adapter I brought is a fake copy chip, and can't be reprogrammed to read the non-standard serial output of the Rover diagnostic port, so back to drawing board on that one. I do have an old BMW cable that I could maybe mod to work but it is designed for CANbus but still has the same serial interface inside it. Anyway was cold and unmotivated this morning and spent half the morning digging thru boxes trying to find my multimeter to do some manual testing. Turns out the MAF seems to giving only a fixed output that changes very little even between engine off and engine running and revving. So I guess thats toasted..has to be about the most expensive sensor in the engine of course haha But I guess that explains the major drinking problem, wouldve been much easier to spot with a diagnostic cable tho to see exactly what the ECU is seeing.
Also took one of the rear spring seat bolts out as a sample to go and get some longer ones in order to flip the seats to accept the cruiser springs. Didnt make it to the shop, and the weather forecast looks excellent for working under cars tomorrow, so maybe not a very productive weekend after all haha

[Crawlerer79]

The MAF in my Disco died too, I got mine for about $180 from LRDirect. They have great prices and super fast shipping (last order made it to the Christchurch depot in 4 days). Highly recommend purchasing from them. If you have the time, the same MAF is available somewhere on aliexpress for around $80, however you have to put up with aliexpress shipping!

[3VILC]

Yup will hopefully source another one during the week.
On a brighter note much more productive today. Rear springs all swapped, and one side of the front done before it started spitting with rain and the wind got up. Managed to snap a quick if awkward angled photo thats hard to tell. I have a sneaking suspicion that the diesel 80 series springs are somewhat longer, cos the back certainly looks far higher than the fronts going to end up..drivers side front spring is in but some of the weight is still sitting on the jack. And I only lost the skin off one knuckle so far

But heres where we got upto anyway:

[3VILC]

Well a few productive evenings in the cold. Got my RoverGauge cable working, confirmed old MAF was shot, put new one in and confirmed that was working ok. Got carried away and finished putting the last spring in so I could go for a quick drive.
Now it looks like this:


Now that problem is that the slight idle hunt it always had is now so bad its all over the place and keeps stalling when warm! Clearly whoever fiddled with the mixture screw on the old MAF had adjusted a heap of other stuff in a failed effort to get it to run better with a f***ed MAF. Although I suspect the main problem seems to be either the trusty idle valve itself or something telling it to move when it doesnt need too. Wound the base idle screw down a lot as it seemed to be way to high, pulled the idle valve plug off at where I thought it should have been fully closed and it was sitting around 1000rpm, however, it was a very steady 1000rpm, no hunting or surging or wanting to stall! The mind boggles. Wound the screw down to around 725rpm-ish, key off plug valve back in and cycle key a couple times to make sure the valve is reset as it should be on startup, and the idle jumps all over the place again, pull valve plug off and its steady again.
Next mission I guess is to use rovergauge without the engine running to force it to fully close the valve then unplug it to check the base idle properly (seems to beat messing around unplugging and squeezing the hose). I believe for that tune the base idle should be about 600. And bring my timing light home and double check the timing is working as it should be but seems to negate that when it idles smooth without the idle valve connected.
Would the typical sticky valve really cause an idle that bad, or a base idle in the wrong place? Or is it some other ecu input telling it to shift all over the place.
I can see on the laptop airflow looks good now, throttle sensor is correctly set. Idle valve seem be showing completely shut more often than it should until it starts trying to catch a stall, then it goes all over the place. From cold it seems to work as expected, starts around 1800rpm then drops in a couple of 150rpmish increments then drops to around 1000, is this normal or indicative of sticking also?
Prehaps also worth noting, I dont get any Fuel Trim readings, despite having O2 sensors. Could it be not going closed loop properly for some reason? Or prehaps the tune resistor has just been changed to use a tune without Lambda correction as the cats have been removed, all 4 O2 sensors are still in place and connect tho.. and no fault codes present for anything

If anyone reading does have any useful tidbits or experiences with this any ideas would be much appreciated
Always fun trying to fix something when someone else has already fiddled with all the adjustments

[Crawlerer79]

If anyone reading does have any useful tidbits or experiences with this any ideas would be much appreciated :

I'm not sure whether I have any useful "tidbits or experiences" but on my blue V8, I had very similar issues to what you had. Once the motor was warm, whenever I came to a stop, the engine would surge up and down, trying to hold idle, before dying. A new idle valve later, and the problem (well, that particular problem) was fixed haha. In Lando, I had a similar issue, especially during the mud plug, whenever I stopped in a hurry (like when my approach angle wasn't quite good enough ), the truck would die. However when I fired it up, it would idle happily... but again was the stepper motor.

[3VILC]

Yes idle valve seems to be the common problem with these. Especially since its idles fine with it unplugged. Apparently it's connected to the speed sensor also to provided deceleration control, but since the speedo works properly and it does it even if you haven't moved I think we can rule that out.
First bet will be to check the base idle is set properly. I have a feeling it's still to high thus the valve can't get the idle speed as low as it wants. So will try that then new valve if that doesn't help. Already pulled it out and cleaned the valve head and seat, but have heard of others actually pull it to bits and CRC inside the solenoid frees it up for a while

[3VILC]

Well for the few reading, finally got a weekend without rain so had another go. Couldn't get the base idle below about 800rpm without the surging and stalling. Fiddled with heaps of things, replaced the vac hoses checked for air leaks couldn't find anything. But still wasn't getting an O2 reading on the laptop, so on a whim I dismantled the interior and found the tune resistor, which instantly looked suspiously not factory. Measured it, sure enough matches up to a non cat UK spec (hence no o2 readings). Oh well we'll change it to the UK cat spec it should be and see what happens. Low and behold it idled perfect, and didnt want to keep stalling. Base idle wound down to 550 no problem probably could've gone lower.
Strange that a simple case of wrong tune could mane it run so bad but it's fixed so I'm happy. Finished cleanING all the filth from the inside just got to put the last few bits back together.

Interesting someone had the thought to fiddle with the tune, and idle, and mixture, yet not figure out the problem was a simple stuffed AFM!

Next mission, recovery hooks.. then go get it muddy..

[Crawlerer79]

Great to hear the progress! Looking forward to seeing it offroad

[3VILC]

Got a few more odds and ends tidied up today, finished putting all the carpets and interior back together so insides all tidy. Still got all the factory rubber mats too just got to give them a clean up and put back.
Fixed the broken front diff breather hose.
Pulled all the facelift plastics off the front bumper..since I see those lasting about 5 mins offroad haha

[Cameron]

Coming along nicely man!