2000 Disco2 4.0 w/ 164,000 miles

Been posting a lot after I had misfires on cylinders 1,3,5,7 with sluggish acceleration/loss of power over 50MPH before the multiple misfires. Went in and removed upper intake and cleaned out all the gunk under the valve covers; while in there I rebuilt all injectors and installed new plugs, wires, and relocated new coil packs thanks to Gerry's Mod.

All but one code remained - P0301.

Compression tested this past weekend and this is what I got:

LH Bank:
#1 (90)
#3 (125-135)
#5 (135-140)
#7 (140-145)

RH Bank:
#2 (160)
#4 (150)
#6 (140-145)
#8 (145-150)

These numbers are all low with #1 being a OMGWTF

So, is it safe to assume I'll be asking for a HG from Santa or is there anything else I should be thinking about?




Compression test results (range)



Cylinder #1 lean

 

Hoping thats just a bad valve. Could also be leaking head gasket. I just had some major problem with misfire found here
https://landroverforums.com/forum/di...episode-86311/
I dont like the look of that plug. Get a borescope and go from there.

 

Do a leak down test on #1 to find the leak.

 

I think your lean plug may help you out with finding where the issue lies, which to "me" would suggest a bad valve.
My compression #s are not as good as yours, and I also have #6 at 90. But I also have several low 100s. I was going through a lot of misfire codes on 2,4,6,8, and was coming to the conclusion that it had to do with the compression. But I found the cause was bad spark wires on 4 and 8. No more codes and it really runs well, even on those compression numbers.
I just bought a bio-scope for my cell phone for $35USD. I will do a look see into my cylinders to see if I can get some clues.

Just looked at your plug again. so, ..Haa, OR, that plug has been steamed cleaned due to coolant getting into that cyl.

 

X1 ........... that plug tells a story, mega lean burn, as already stated, probably a valve. A borescope is the initial option but it won't solve your problems only possibly tell you what might be wrong inside.

Check RAVE for the correct cylinder pressures albeit they may be down a bit but they should all be within 20 psi of each other.

 

Thanks everyone! I did perform a leak down test and the dye never changed color - stayed blue at start up and while at operating temp.

So when you say bad valve, what exactly should I be looking for and what would the corrective procedure be?

 

Leak down test is different. You use shop Air to pressurize a cylinder while the valves are all closed. Then you can find where it’s escaping.

you tube leak down test and you will see