So, I had a slight knocking noise in my 98 Disco after I got it. Only sporadically, and only at idle. Now, after running a can of seafoam through it and putting on new plugs *bosch platinum 4s* it's gotten worse. Any ideas?

My disco has 112000 miles on it and I only run Premium gas; however I just got it, so who knows what the previous owner ran in it.

 

Did you do a induction cleaning? Is that what you mean by runningthe SeaFoam through?

 

Hey man, no sorry, I just put it in the gas tank.

 

Ok, heres what I would do. Do a search on here for"induction cleaning" or "seafoam" and start by cleaning the carbon out of yourengine.
Did you replace your plug wires too?

 

Hey Spike. Not yet I haven't. I've been doing one thing at a time. The plug wires and cats are next, then o2 sensors. Thanks for the tip. I'll do that next and see if that helps out. I appreciate it man.

 

I really think it is your plug wires. When they go bad they can short across to the exhaust manifold and that arcing can sound like a ticking noise.
Keep plugging away at your truck, it sounds like you really want to take care of her.