Well, I DID IT!!!! Only took 4 hours... ugh, but I can knock it out next time in 2 hours or less, i bet. I did have a couple of snags, though. SAI tube was the most time-consuming to get out, because i was worried of breaking it or something else around it, but once you know the trick, no problem. I did go ahead and take off the bracket for the SAI but now i wish i hadn't. It must have been an issue for the PO as well. It only had one screw instead of two. When I went to replace the bracket, the holes from the coil packs were off-set and I had to use a pry bar to bring it back into place while screwing in the bracket. Well, that was no fun and I ended up loosing the screw. SO - I'm running without a SAI bracket until I can find the replacement screws for that bracket.

I also broke the plastic up by my windshield. That grille where the filter is supposed to go needs to be replaced now. It was so brittle and didn't like my elbow, hand, or anything else i touched it with. I found myself sprawled out over my engine to get my coils in. A step stool would have worked but i needed to get access from top and center.

I am grateful to everyone posting on this thread. My truck runs awesome now and it only cost me $225 and four hours. Learned a lot, had some fun and yes, I'll be sore for a couple of days. Next project - replace brakes on my wife's LR3.

 

I have replaced mine without removing anything but the old wires. You have to have skinny hands.

 

To DeepBlueWater – many thanks for this post I found it extremely helpful as I brought in the New Year by replacing my plugs and wires. The SAI tube in the back was indeed the biggest issue with this task and there is no way I could have done this without removing it first. I found my heater hoses in the way to get it out and since I needed to replace them anyway I cut the heater hoses to remove them (they seemed to be melted on to the connections and I had enough trouble even cutting them with a razor knife in getting the old ones off!) I started at noon, took serious breaks from lying on top of the engine, and at 8:00 pm I was test driving and smiling brightly. I am posting a picture of the SAI tube out of the vehicle for reference - the bracket secured by two 10mm nuts is clearly shown. The only casualty was I snapped of the IM fitting to the PCV hose and have a new one ordered. I can offer the following additional suggestions to someone attempting this task if you have SAI:
1) Schedule at least half a day for this, take your time, and allow for extra time as you may need it going back together with everything. I found my throttle body heater plate corroded and leaking so I put in a temporary fix with new RTV until the new one arrives. The heater hoses take some time as well, especially if you need to re-use them.
2) Label your old spark plug wires as you take them off. Compare the wires to your new set and label the new set. Double check the length of your wires and your labels. The last thing you want after you are in position is to have a mislabeled cable.
3) Take a picture or two of the top engine areas on the driver’s side after you get the MAF and related hoses off. You will need this as a reference when you go to re-install the SAI pipe. I did not and had to redo a couple of things where the throttle cable comes up and around with the SAI pipe routed through all this.
4) Get some long reach pliers, extra long socket extensions, a socket swivel or two, a remote LED light, a headlamp light, and an inspection mirror. I had a craftsman pry bar with an angle that was perfect for seating the coil ends from above. I was able to check with the mirror and remote LED light that each coil end boot was flush with the coil pack in its proper position.

 

BAM DONE! not too difficult! I do have 03 Disco with SAI .. just pull a few items off like stated and I used a metal bent slotted panel removal tool! looks like a screwdriver but has v but out of center and a little wider at tip... but basically screwdriver size ad stated above.. BAM was pretty easy! This was my first time changing plug wires on my discovery even though I've done lots of cars in past ... once SAI stuff was off... my Kingsborne 8mm blue wires snapped right on! i would ave gotten magnacore but back a few years ago when supposedly stealership put new 7mm wires on, I didn't do it an was already over budget so ordered the Kingsborne and there they sat.. year after year.. finally I took a FUGITOL and BAM! 2.5hr job! clean up and search for tools 30 mins total 3 hrs ! and NO CODES! I was pretty sure I had bad wires or plugs... I did replace 1 plug and waiting for my platinum +4 to arrive and Ill switch... however I do have a set of iridium so Ill ask here which I should use... I heard the platinum _4 were being phased out so I bought them just in case... ! also noticed a few loose clamps and battery terminal leads were not snug ! when checking voltage before and after job... I was getting 13.6 ish on the UG and now 14.6!!!!! I full volt more!


[UPDATE] Everything is running smooth... the voltage difference seems to have just been at initial startup and has been bouncing around 13.8 to 14.2 so I do see a little better there... the engine is running smoother but I have thrown a couple codes I was already getting.. 0134 / 0135 / 0155 ... I know after looking that I do have some mix n match spark plugs.. I just noticed I have a Denso in Cylinder 1 and I swear I put all new iridiums.. maybe I did half of them because my local store was out... its possible but that was a few years ago so I don't remember... lol Ill check them when my new Platinum +4 arrive

 

One other thing for anyone doing this... the rubber hood seal that seals the hood down at firewall... lift it up and you can lift off those metal wiring loom clamps that ARE IN THE WAY!! popped mine off and the other parts and it was fairly easy to get in there.. one thing for newbies to this is... once you get the parts off... and have a good light in there.. they are not hard to see.. you can see pretty good! I was really afraid of this and something going wrong and being stuck till another day in the hot south florida sun... Started at 10:30am and done around 1pm sun was just starting to become less enjoyable with the warm humidity lol

DO NOT BE AFRAID OF THIS JOB!! same for the upper and lower ball joints... its strait forward... not too many parts... take time... take pics... and get the right tools.. I rented ball joint clamps

 

or you could spend 20 minute and disconnect the upper intake and move it out of your way.

 

yup... I think now this is more of an "in the field" fix by not taking upper off... lol its really not that difficult once you have done it once... I bet now I can do it in 1 hr when I had my tools ready... i could slap myself silly for not doing this earlier lol I pictured worst scenario which I have done on most of my work ... now that Ive don't everything from disassembling doors and actuators to ball joints.. I really haven't had one job that was REALLY hard... some took some time but were realistically easy... even rebuilding drive shaft codes have been a little bit of issue here and there but no blinking check engine light except when battery failed ... when I first got truck... and a pesky 3 amigos here and there

 

I just replaced the plugs and wires using this method. I think next time I'll take the UIM off. While this was doable (and without the bent screwdriver), it was more time consuming than I had thought. Truck has SAI, so that didn't help at all. New Magnecor 8mm and Denso IK16 plugs.

 

Is there any way you can email me this step by step procedure so I can provide it to my mechanic? If I had time to attempt it myself I would but I have a reliable friend who works on my Disco. I just purchased 8 Bosch +4's and a set of STI wires and plan on doing the plugs/wires on Fri 3/20/15 when I get back home. I save lives for a living, it is difficult saving Disco's at the same time so I usually hire it out... Thanks in advance Sir.


mallin1116@yahoo.com

 

10 or so bolts and your mechanic can move the upper intake out of his way, it does not have to be removed from the compartment just moved out of the way. Some people take it all the way off which is why it is so much work.
you might want to rethink those STI wire mine only lasted about 18-months