Just purchased this one-owner 2003 Disco with detailed maintenance records. Drove it home in 95 degree weather and started hearing a knock between 0-2000rpms. I’ve read about 200 of these posts so apologies for the newbie thread. But maybe a more senior member can help me discern this particular sound? It isn’t super loud but might be a slipped liner? Or is that typically louder?

https://youtu.be/iQa6aRiX4p0

 

seems much too fast to be a slipped liner. And it wouldn’t go away with higher rpm, although they usually Only make noise once it’s warmed up.

here’s a video of a slipped liner:

hard to tell in a video, but you can use a long screw driver help up to your ear and place it around the engine and see if it you can pinpoint the noise.

any codes? Any lights on the dash?

off the top of my head would be:
-lifter tick
-valve train noise (broken valve spring?)
-evap purge valve can be noisey
-SAI valves (the little water tower looking things on each side of the engine) can be noisey, but they have a higher pitch sound.
- pulley going bad perhaps?

I wouldn’t ignore a sound like that. It isn’t normal

 

Ok, great intel. I have an appointment on Monday to review and will use this as a guide! Ty!

 

What weight oil is in that Disco, rockers typically tick - here is an example ignore most of it but you can hear the tick

 

Doesn’t sound like liner to me.

I voted oil gunk because that’s the closest poll option to the absolute first thing I would do…. Which is change oil with 15-40w. When doing this, investigate the oil that comes out and look for metal shavings, gunk etc.

the noise is really to loud for lifter noise. Imo

 

What do the maintenance records say as far as oil change history? The engine/bay seems clean, how many miles? I agree that it's too fast for a liner. Screwdriver trick is a good start. At least see if you can isolate it to the top or bottom half, and if it's louder on one bank or the other.

 

I would just drive it. Mine has the hot idle tick that leaves immediately on throttle input but runs great. Get your coolant temps under control with the Extinct thermostat mod and get a UG & oil pressure gauge. If both of these are showing decent numbers drive on.