1993 pickup 22re. I have this strange sound when I first start my engine or when I hang around 2000 rpms for a while and comes and goes randomly when downshifting or clutching between gears. It's coming from the valve train so I think it's a ticking lifter but I'm not sure. Since it mostly only does it when I start the engine I thought it might be a hydraulic lifter that wasnt getting oil right away. It's a fast paced rattling noise.

 

Could be the timing chain the tensioner uses oil pressure to actuate so at start up it is loose until it gets pressure from the pump. Pull your valve cover and look at the chain guides, my bet the plastic guide for the chain is gone and the chain is contacting the timing cover eating it away. 22re's do have loud valvetrains it could be a loose valve. They don't have hydraulic lifters.

 

Ok. I just gave it a valve adjustment thinking it would fix the problem. It did for a while but now it's back. I agree that that's probably the problem, but is there a reason why only around 2000 rpms is when I can hear it?

 

Did you look at the timing chain guides when the valve cover was off? Are they intact? OE plastic guides break easily!

 

No I didnt. I'm pretty much teaching myself about all this stuff with a little knowledge that I'm transferring over from working on dirt bikes. I'll have to look again. How much work is involved in replacing it if it is broken?

 

Ok so I had a friend check it out again today (yes its still doing it). We found out that the sound is coming from somewhere near cylinder #4. His idea was that the spark plug wire might have a loose connection, but since it only makes the noise on startup (until oil pressure comes up) and around 2000 rpms it doesn't make sense to me. The thing is that wire actually pulled out of the clip when I replaced my plugs last time and may not have a good connection. So if thats the case my guess is the wire is arcing out on the clip or unburned fuel is igniting in the exhaust manifold.

 

I have the the same problem and can't seem to find the problem either. And my spark plug wires are like yours to the clip came outta the wire

 

If you over tighten the valve cover bolts, the rockers can make contact with the cover. You might even see a shiney spot on the rocker or the cover if it has been doing it a while. This could be the source of your random rattle sound.

The valve cover bolts should only be tightened until you just barely see the rubber under the washers start to compress. If you tighten them to factory specs, they will pull the cover into the rockers arms.

 

This happened before i even took the valve cover off

 

Same with me. I have been driving mine for like 8 months like this and put 10xxx miles on it with the noise hasn't gotten worse or better so I try not to beat on it so it'll last longer

 

really sounds like a timing chain

 

Mine gets louder as the engine is warmed up. So when it's cold it's not very noticeable but once it fully warmed up its loud