Had a misfire code on cyl. #5 shortly after replaceing plugs and wires. Plugs where iridiums and not sure of wire brand (cost near $100). Since then I have ordered the magnacore wires and got a set of bosch plat 4's which I plan to replace this weekend. In addition I have also done the throttle body cleaning recently and the seafoam treatment.

Question- when inspecting the plug in #5 I noticed it was unusually difficult to break free and continued to betight while removing.The motor was not warmso I do not believe expansion was an issue. Honestly can not remember ifI used any anti seize or not. Hope all are not as difficult. Any suggestion for easier removal if they are???

Also, just this week noticed truck starting to idle much ruffer than it had been, have not had a chance to get codes read yet. Could this be related to the misfire and is it typical for it to get rougher as time goes on?

Thanks

 

I'm not really sure why they tell you to remove plugs when the engine is cold. I have always found it to be much easier to get stuck plugs out with a warm engine. I guess a warm engine could free them up - a hot engine might cause expansion issues though. Make sure to use anti-seize.

 

Once you get that plug out, I would inspect the threads for metal filings and re lube it. If it doesn't go back in easy from the start remove it and run a thread chaser the the plug hole. In the future, I wouldn't replace a plug without proper plug lube.
Also, do not change out your plugs untill after you have replaced your wire, if you are still having a problem call me before change the plugs. I am currently using Bosch Uridum plugs and really like them, prior to that I put 65,000 miles on a set of Plus 4's that I swear by, they were super.

 

Are the plugs gapped properly?

 

Changed plugs and wires on Saturday, only #5 was tough to remove all others came out like they should. Truck runs much better, misfire codes gone!. However I heard a nock which had not been present prior to changing plugs, any relation? Still have code P0304 and P0305. Going to change out Oxygen Sensors next weekend and should remove those codes. P1590 still remains, any ideas?

 

Who's plugs and wires did you use, what plug gap did you use?
304 and 305 are mis fires related to either plugs or wires, unless your engine is so carboned up that the carbon is causing the misfire and knock.
How many miles on the engine?
The 02's will not cure the misfires.

 

my apologies Mike, posted wrong codes. Codes I still have are P0154 and P0155, which O2 sensor should fix.
The knock is a new concern however.
I used Bosch Plat. +4 and Magnacore wires.

2000 Disco w/ 136000

Thanks