while im driving and it gets up to around 2900 rpms it makes a rattling sound. I thought it would be a loose exhaust heat shield or something. Anyone else had this problem?

 

wheres it coming from?

 

im assuming the engine, but its hard to tell cause it only happens when im driving. I guess it could be down the drive line somewhere, btw i have manual hubs so the cv's aren't spinning.

Can u-joints make this kind of noise?

 

it probably is. take it to the WDFW shop and get a state employed grease monkey to listen to it.

 

lol, WTH is that supposed to mean?

 

Sounds like it might be ping to me...

 

engine detonation wouldn't be good, I always though engine detonation sounded like a spray paint can being shooken up? (i've obviously never heard ping before) But i've also been told it has a metallic sound.

 

It sounds like a couple of marbles being shaken in a can, or a "rattling pulley." If it consistently occurs under load at certain rpm ranges only, my money's on ping.

To fix it is a whole 'nother issue. How old are your spark plugs?

 

I changed them about 1000 miles ago after a head gasket job, also the fuel filter and wires. My timing is set to 16 * so I will changed that pronto and see if the noise dissapears. Wouldn't some octane additive work also?

 

I figured you worked for WDFW cause of your thumbnail... anyway, if it sounds like a vibrating heat sheild, it probably is. does it do it in neutral if you rev the motor? if so, have someone rev it while you crawl under there and find it. if you need to take it in, you can do it on your new furlough day!

 

pull valve cover and check timing chain wear. there are a lot of threads on the subject

 

He has a 3VZ-E.

16* advance sounds high to me, maybe try dialing it back and see what happens. What's standard for the 3VZ? 10*?

 

on my trip down the hill today did about 15 miles with the revs at 3800, at least on mine i think its them noisy injectors talking when there getting used pretty hard

 

Noisy injectors don't sound like marbles in a can, unless there's something very wrong with them and then they would be loud whenever the engine is running.

 

check u joints and driveshaft bolts. I had bolts come loose and it would vibrate/rattle.

 

If you grab the driveshaft you should only have a tiny bit of play in the ujoints.

 

Oops.

 

I've had a loose heat shield over the cat - get underneath (when it's cool) and start pushing and pulling on things, or tap around with a rubber mallet, then wire it up with bailing wire. Also, a loose heat shield is WAY louder when you roll your widows down, preferably next to a building or wall, to bounce the sound back to you.

Have you done your water pump (ever)? I had a faulty water pump that sounded like something rattling around in the intake manifold. Check my profile thread in my sig to see what it did to the belt and pulleys - yuck! (I think it's the last post of my build thread)

If it only happens under load, it's probably ping (although ping can happen otherwise). I always think ping sounds like clicking more than rattling, but that's just me. A quick fix is to run high-octane gas and see if it's better. If so, then it's time to consider a valve job or better plugs/wires. Regardless, find out what it is quick so you can get it fixed if it's serious.
Good luck!