Last summer I swapped the 4.0 out of my 98 Discovery for a Bosch 4.6. Used the Frankenrover website to pretty much guide me through it. So basically it is a 4.6 block and heads with everything else from the 4.0.
She ran fine after it was all said and done except the head gaskets started to leak. Never overheated. I could see the leak towards the front of the heads. So I brought her to a shop to have the head gaskets done. Unfortunately she had to sit for several months before I could pick her up from the shop. They would occasionally drive the truck for me in the mean time.
Fast forward to now and maybe 1000 miles after the headgaskets and the truck has these codes:
P0300 - Random Misfire
P0308 - Misfire cyl 8
P1314 - Misfire Catalyst Damage, bank 2
P1313 - Misfire Catalyst Damage, bank 1
Replaced all spark plugs NGK BPR6ES and wires 8mm Magnacore. Originally had magnacores that looked beat so replaced with NGK's I had laying around until the new wires came in and still got the codes. Cylinder number 1 plug had excessive gap, >.050, when pulled but all plugs looked fine.
Truck appears to run just fine without stumbling or rough idle. Even gets 13 mpg on hwy with roof rack lift and HD bumpers. I also didnt have these codes before the headgasket job. I put a few hundred miles on the engine after the swap.
Thought possible bad gas clogged injectors so ran full bottle of seafoam in gas, always 93 octane.
Cats have under 50k miles but could have gone bad from driving around with the apparent misfire.
I am going to check the tabs on the flywheel in the inspection plate to see if any of those are bent.
I have not checked compression yet.
Any other thoughts?
She ran fine after it was all said and done except the head gaskets started to leak. Never overheated. I could see the leak towards the front of the heads. So I brought her to a shop to have the head gaskets done. Unfortunately she had to sit for several months before I could pick her up from the shop. They would occasionally drive the truck for me in the mean time.
Fast forward to now and maybe 1000 miles after the headgaskets and the truck has these codes:
P0300 - Random Misfire
P0308 - Misfire cyl 8
P1314 - Misfire Catalyst Damage, bank 2
P1313 - Misfire Catalyst Damage, bank 1
Replaced all spark plugs NGK BPR6ES and wires 8mm Magnacore. Originally had magnacores that looked beat so replaced with NGK's I had laying around until the new wires came in and still got the codes. Cylinder number 1 plug had excessive gap, >.050, when pulled but all plugs looked fine.
Truck appears to run just fine without stumbling or rough idle. Even gets 13 mpg on hwy with roof rack lift and HD bumpers. I also didnt have these codes before the headgasket job. I put a few hundred miles on the engine after the swap.
Thought possible bad gas clogged injectors so ran full bottle of seafoam in gas, always 93 octane.
Cats have under 50k miles but could have gone bad from driving around with the apparent misfire.
I am going to check the tabs on the flywheel in the inspection plate to see if any of those are bent.
I have not checked compression yet.
Any other thoughts?