Just yesterday, my XJ started doing this. After running for about 5 min or so, when you rev the engine, it has a slight tick at about 1800 RPM. It also "shudders" like it's missing or misfiring. The noise doesn't get louder at higher RPMs, but I never revved it that high since the problem started. I recorded a clip, but it's kinda hard to hear:


I got this thing put back together earlier this week from replacing the head and has been driven a few times since then. No problems until yesterday.

I did pull the valve cover off and checked the torque on all the rockers. All were still right where they should be. I also made sure all the bolts for the manifolds were tightened down as well. Could this be a bad lifter or something a little bit more serious?

 

sounds like a dead lifter.....Specially if you have a miss...DID you replace the 2$ a piece lifters when it was apart?

 

Doh! If I would have known they were only $2 a pop I possibly would have.

I also forgot to mention the oil pressure seems low as well with 5w30.

 

i run 10w40 and i think stock is 10w30...

 

Just curious, where did you get the lifters for that cheap? Found some at Advance for $4.49.

 

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