ticking or rattling at idle only

96 4x4 2.7 5spd 145k miles. it has a rattling sound at idle only. the first time i start it in the day after its been running for about 30 seconds to a minute the rattle/tick starts. Any rise in the rpm's the ticking stops completely then as soon as it goes back to idle the rattling starts again. no loss in power, mpg, or anything like that runs great just a little worried about the noise. im guessing its not the valves since it stops as soon as i hit the gas. also guessing its not a exhaust leak for that reason also. anyone have any ideas?

also its not a the same rythme kinda noise.

 

Bump bump

 

hmmmmm

 

does it tick louder when you give it a little gas? cuz my truck does that too

 

Check lash on your valves, one is probably a little out of tolerance.

 

Heat shield on exhaust manifold or possible cat, had the same issue. My heat shield mounts were broke and the cat would rattle due to bad rubber mount bushings but under throttle it'd go away.

 

Mine rattles at idle, when I push the clutch in it goes away. I know it is the heat shield and need to get it fixed.

 

doesnt tick at all if i give it gas only ticks at idle more of a rattle sound. also its not the manifold or shield i checked them out. and i just replaced both o2 sensors and cat. runs great no cel or anything just wondering what it is.

 

how can i tell if its a check lash and will that cause any issues?

 

You have to pull the valve cover and get some feeler gauges and measure the clearance between each cam lobe and the shim that the lobe rides on. It can cause issues if not taken care of eventually, record your measurements on a piece of paper for each intake and exhaust valve then compare them to factory specs, if out of the given range you will have to order new shims thru toyota and then install those on your motor. Hint sometimes you can switch shims with other valves and get them back in spec that way but not a gurantee. If this sounds confusing your better off taking it to a capable mechanic as it is a little involved, but at least spec out your valve lash clearances as anyone can do that. Good Luck man

 

ive been doing alot of research on valve lash almost every search ive done and every video ive watched if it where valve lash the noise became faster under throttle the noise on my truck dissapears as soon as there is any throttle. im stumped lol i almost dont care because it runs great just a little annoying.

 

Same problem. Valve lash in spec. It's something else.. hmmm.

 

I have an 09 and when my A/C is on at idle it ticks and rattles. Then i push the clutch and it stops too hmmm...

 

Sounds like TOB is your problem if it is clutch dependent.

To OP if you checked your lash then i don't know what to tell you, maybe post a video of your noise. My lash is outta whack but i have no time for my stuff fixing everyone elses problems. Good Luck to you guys.

 

i will try to get a video up today or tomorrow.

 

my 06 does the same damn thing. mine kinda sounds like a loud fan on a slow speed, idk how to explain it but it pisses me off sometimes

 

update video

http://s810.photobucket.com/albums/zz30/raymond131ll/?action=view&current=MVI_1384.mp4

 

Not sure how to do that but i was thinking it was the timing chain also.