3 years ago i replaced the plugs, wires, and coil packs on my 02 Disco. Yesterday I was driving and the SES light came on. Cylinder 8 misfire. Has to be way too early for it to be any of the things i replaced i would think. I havnt tore into her yet but anyone ever had cylinder 8 only misfire? If so, what was your experience? Anyone got any ideas what else could cause this. 74K miles.

 

push on the spark plugs to be certain. but if they are good, take a look at the old plug.

did you have any issues before changing the parts.

 

So i took the old plug out, from the color and everything it seems to be firing normal and no signs of it getting wet and its not clean as if it were getting coolant on it. I noticed however that my battery was corroded and a little swollen on one side. I replaced the plug, reset the battery, and so far she is running fine. I just hope replacing the plug wasnt a temporary fix because plugs usually dont foul for no reason.

 

What brand of plugs and wires did you install, how many miles on them now? This was a temp fix, most likely.
As for the battery, if your battery is leaking, it is about to fail so start pricing new ones that have over 800 CCA's.

 

I used Bosch Platinum plugs and wires it calls for not the Magnicore ones. The new plugs and wires now have about 30K on them.

 

I think i just heard some sloshing behind the dash as well. Coolant level is fine, oil is fine, heat works, never overheated. Hopefully just some air that needs to be bleed out, it drove fine all day today however without the SES light cming back on. Taking it to my mechanic on monday for a coolant pressure test and cylinder test.

 

Save your self some money and bleed the system a couple times this weekend when the engine is cold to get rid of the sloshing sound.
If your SES is not on, the shop won't be able to help you.
By the way, Bosch wires don't hold up well on our trucks.

 

UPDATE: So i bled it and got the air out, runs good. However, i had my mechanic run a test on it and he thinks there could be a leak at the heater core but was for sure. He said in the future i could have to replace the heater core. How long do these things usually last? Also, just curious is there anyone on here with a disco that has high mileage and never had to do a head gasket job?