okay so I have a 2k disco II 166k on her. she runs great and is very clean. she had a whole host of issues when I got her but I have managed to cure one or two illnesses a week. I have had it about a month now. what I have done, or was done when I got it.
water pump, upper coolant hoses
head gaskets(apear to have been done)
180 t stat
no dex
rotella 15 40 purolater l40316
85 140 in all the diffs
trans flood & filter
ultra gauge.
water wetter
fan clutch
spark plugs (got em not in yet)
induction cleaning today

okay now for what I still need to do and or am having problems with. I have a series of problems that are most likely compounding each other. first my plug wires are clearly older and need replaced, I have read up on magnacor sti and kinsborne, I will get that done soon (maybe this weekend). I am seeing that my bank one upstream is flat-lining and runs very week. At cold temp when first starting it runs parallel to the bank 2 upstream, but 10 minutes into the drive it weakens and will eventually read .000 at some points. now there are a couple other issues. one my exhaust flange is missing a stud and i had a leak, I tightened the two, but I don't know the thread size so i was hoping someone would have that info so I can get that other bolt in there today. so I am 90% sure the o2 is bad or a bad connection since all three read together and one is in left field, well the two downstream are consistant and the up stream two is very consistant. but since i have a small leak and plugs and wires are needing done(have plugs, doing today). and it is the side with the leak and everything I hate to buy sensors yet. she is running crazy rich, even for a disco, so I need to start getting some stuff running better quick

okay so I have rambled for a bit, but does anyone have any input.

oh also i have a seeries of vacuum lines on he firewall running from driver to passenger side, they seem like har plastic or something, one of them just stops behind the motor, cant figure out if it should be hooked to something

 

The exhaust studs are 8mm, the open ended "vacuum" line is quite possibly the vent for the front axle (hard to say for sure since I'm not looking at it but that's where mine goes)

 

I/we need the actual fault code numbers to be able to help you.

 

okay

1590
150
130
171
1171
305
1319

and the tube does appear to be a vent, when I traced it that was my thought

 

also on the stud 8mm, can I just get a hardware store bolt? or could I tell autozone I need an 8mm exhaust stud?

 

You could use a bolt, it would probably be easier to find than a stud. I prefer to use a stud and a nut in a cast part (exhaust manifold). First you need to be sure the stud has fallen out and not broken off, take a piece of wire and push it in the hole and make sure it goes to full depth. Then I always run a tap into the hole before attempting to put a new stud (or bolt) in. The tap size is 8 x 1.25 and is a handy tap to have, that size is used on many places on the truck. Good luck

 

perfect thanks! yes I have a craftsman 200 piece tap and dies set! I can tap anything... hmm... anyway.... I will go get a bolt and it definitely isn't in there I can see through it.

the truck runs a purrs like a kitten, and then it just starts to idle rough and and the 02 starts running low.. so I'm thinking it isn't mechanical, cause it comes and goes. I'm really sure my plug wires are half the problem... I really can't afford magnacor for a couple months. can I just run borg warner or bosch till winter and then switch? I have my temps under 200 at all times. I'm running 188 on the highway and 194 at idle. will that help teh life of the wires?

 

Install your new plugs and 8 mm silicone wires, clear the codes and other the the 1590, 3 Amigo code, the rest should go away once you have corrected the exhaust leak.

 

one more question. do you guys do the indutcion cleaning on a hot motor or a cold motor? I undestand is has to be running to siphon the seafoam, but start at temp or cold?

 

I have found I get better results on a warm engine then let it sit for up to an hours then drive it hard till it quits smoking.