Hi, i need some help with my disco. i have a 03 land rover discovery 2 with a 4.0 i swapped in cause the 4.6 sleeves were tapping to loud and i think had a cracked one cause air was build up in coolant system. so i got a 01 land rover discovery 2 with 150k miles on it. it started ran good shaked a bit but didnt drive. Trany was dead. I changed head gaskets lifters, pinned all of the liners and changed crank and rod bearings before putting it on my 03. anyways i changed all spark plug wires, spark plugs. It is slow at acceleration and about 8mpg. Pulls really slow. my Friend has a 2000 disco with same engine as i do and when he floors it he is gone my wont catch up to it
I have no lights on dash. my friend scannd my rover with his snapon scanner and two codes showed up.

p1000 (40) Catalyst deteriorated bank 1
P0441 Evaporator control system fault.

i tried removing both o2s and try running without them. no gains

 

P0441 = Purge Control Valve, just grab an OEM Hyundai unit for 10-20.00 online and that will solve that. Air filter clean? Good fuel pressure? Both my 4.0L’s will rev up & go no problem. Does it rev up fine? Or bog down? How about the throttle cable? Is all the slack out of it? Should have like 2mm before it touches the throttle body plate (both cruise control & throttle body cable).

 

air cleaner is clean. not sure about fuel pressure. it revs up fine. is there a way to upload a video here? i could record and post it here.

i did compression test here are the numbers

#1. 155psi, 275 wet
#2. 200psi
#3. 190psi
#4. 155psi 300 wet
#5. 220psi
#6. 196psi
#7. 175psi
#8. 195psi

was told by a friend that was a military mechanic that my compression isnt too bad and wont lose all power it lost. he said that i need to change ecu from a 4.0 and that should fix the problem???.

 

0441 has been appearing here too... Is this the correct part?
Also for the loss of power and mpg issue, you might want to check for vacuum leaks.

 

This is the one I highly recommend (OEM Hyundai Unit).

 

The compression is your issue.

 

For the shaking? I know but what about the power lose?talked to few mechanics they all said if it would have under 120psi than yes that would cause power lose but 150 is still good