Was port matching my intake today and i was cleaning it out with some brake cleaner and all of a sudden i hear "tink tink tink" inside the intake.... well my 2000 had a severe engine failure on cylinder 4 when i bought it. Pic below. And then i installed a perfect running engine from a 98 xj in it and it "coincidentally" started to knock and had some light scaring in a cylinder of an engine that was perfect when installed. Well back to the tink tink tink noise from my intake... Apparently when the previous engine grenaded (like this when i purchased) it blew about and inch total of pieces of piston ring up into the intake because when i sprayed the break cleaner inside it it broke them free and they fell out on the ground. To make matters worse when i started haviing issues with my xj after i swapped the motor in i pulled the head and found on of these pieces in there but i had assumed it to be a coincidence. All i can say is thank god they came out before i put that intake back on my new 4.6 stroker. Now i really wanna punch the previous owner of this jeep in the ****ing throat! Ill grab a pic of the pieces tomorrow.