So my D2 has developed a knock in the engine. Only had it for two weeks so far, so kind of a bummer. Just started to knock yesterday. Engine performs excellent other than the knock. I've changed the plugs today, didn't notice any indications on the plugs of coolant in the combustion chambers. No coolant in the oil, just changed it again yesterday to Rotella 15W-40 from Castrol 10W-40. Honestly, neither really helped. I don't think it's a bad lifter or cam realted. Sounds like it's coming from the bottom end, definitely on the driver's side bank. Is it rod knock or a slipped cylinder? The recording attached is from the driver's side in between the fender and the tire.

 

Not an expert on slipped sleeve syndrome (copyright pending) but that doesn't sound like a slipped sleeve that I have heard before- I am guessing rod-

 

If it taps or knocks on a consistent rhythm I want you to try this.Start the engine and listen to the noise and see if its coming from one cylinder. Stop the engine and pull one spark plug wire off at the plug. Start the engine, did the sound change? if it stopped knocking then that is the cylinder with the issues. Check each cylinder by pulling the plug wire, start listen, then put the wire back on and go to the next cylinder until you find the one that it knocking.

If when you pull the wire on the cylinder and the noise stops, its likely a bearing. if it still ticks its a cylinder sleeve or a lifter on the camshaft

Report back, I hope I can help

 

I'll check that. Also forgot to mention, only knocks at operating temp. At least that's when it's noticeable.

 

O geese not another one. Guys there exists dozens of threads just like this. Search them. You will never get a definitive answer tho in this subject.

 

Listened several times, is that a short pause I hear about 3 times? Have you checked all your drive pulley/idlers and flex plate fasteners? Sounded somewhat similar to mine when the belt tensioner was jumping around. What happens when above idle speed?
......

 

 

I have an 03 I'm working on (customers) that sat for nearly 3 years after it's transmission/transfer case exploded due to a drive shaft. It did not run when he bought it, and after removing 3 years of nest and debris I came to the conclusion the CPS was inop. Replaced it and got it running. I couldn't hear the engine all that well as the exhaust had also been ripped apart in the drive shaft explosion. I've now got a set of cats on it, and just like your D2 once it reaches normal operating temps it makes the same exact sound on/off.

When I changed the oil it was black as night and just nasty (however it was quiet with whatever was in it), once I changed it to some 15/40w it started to make the sound. It's not a tick like a sleeve, but more of a lifter sound. It runs perfectly smooth, idles smooth, but once warmed up the sound shows up at idle.

 

Well the idler seems OK but the tensioner pulley bearing is shot, feels really crunchy and loud when I spin it by hand. Whether it's the cause or not, it needs to be replaced. Thinking of buying either a Dayco 89287 or Gates 38245. Is one better than the other?

I was going to try removing a plug wire and see what happens but I couldn't get it to make that sound again today, even with 181*F coolant.

 

I bought a Gates Idler Pulley the other day. It's made in Canada and it's metal vs plastic.