thenewguyy

Hey guys, so im getting this fairly loud rattle at startup, feels almost like the engine is being thrown around, i did change my passenger side mount not too long ago, im assuming one of the other 3 are bad? Which one would it be exactly? the driver side? aka transmission mount?

rodent_infested_03

Whats the status of the oil? Is it recently changed? What viscosity grade/thickness? Is there a consumption problem? Are you topped off?

Turbobink

iTrader: (2)

How about a short video with sound?

Honestly, when I hear folks say "rattle at startup" my first thought is timing chain tensioner.

But ... without more specific information that's just a guess.

SubwayVQ

I agree. I’m in the same boat as OP and it only happens when there is no oil pressure. Running, no sounds at all.

Turbobink

iTrader: (2)

This is the typical when it comes to the tensioner in the VQ ... a couple of seconds of rattle/clatter at startup and then gone.

It's not necessarily a big deal unless the clatter persists even after the oil pressure comes up. Then, the typical fix is a tensioner replacement, likely not a chain guide replacement, but a tensioner replacement.

I've personally switched back and forth with oil viscosities and find that the startup clatter is minimized with a 10W as opposed to a 5W and conventional oil seems to keep things quite more than a full synthetic.

freezer

I'd say I'm experiencing the same noise as the OP. It's not the tensioner rattle, I also think mine's a motor mount issue. I've got ES bushings on my lower mounts which contributes to some harshness. The side mounts looked OK but maybe they need an upgrade.

thenewguyy

Ok so I found something regarding the oil that might or might not have to do with this. So a week ago, I topped off my oil. Well forward to today, i open up the hood and theres no oil cap!!! I somehow forgot to put the oil cap back on....yea tell me about it. Well heres the thing now, first thing i did was go to a local autoparts store and get an oil cap. At this point its been without a cap for about a week so not sure if it would make a difference but I have to get one regardless so did. Now the other puzzling thing is, I did not see any oil spots anywhere, nothing under the hood, engine bay is clean like a little dumbfounded since I thought I would see oil splattered all over the engine bay. Then I proceeded to check the dipstick and theres oil, it hasnt completely sputtered it all out and its not low, like its in the middle of H and L, basically at the level it should be since I added a quart of oil in it when it was low. So thats my story in a nutshell but for some reason, this doesn't sound like an oil issue, the fact that it recently started and this episode happened at the same time is probably more coincidental than one being the cause of the other but im guessing here from the kind of noise its making. I posted a quick short video here
https://photos.app.goo.gl/CMhEhrhbyA6T3Hq63

Here you go, https://photos.app.goo.gl/CMhEhrhbyA6T3Hq63
It literally just started, hope its not timing chain issue.

Look at my video, doesnt exactly give you the full picture but at least you can kinda get the jist of it
https://photos.app.goo.gl/CMhEhrhbyA6T3Hq63

You think so? Yea i do 5w-30 since thats whats recommended for summer/winters

Derrick2k2SE

iTrader: (3)

That doesn't sound like the timing chain rattle. The chain rattle really isn't a big deal as long as it's just at startup.

Could be the mount near the front of the engine over the belts.

I'd have someone start it while you watch with the hood open. It could be anything loose under there. The air box, overflow tank, fan shroud or even the engine cover. I once worked on a car that had a constant rattle and vibration under the hood. Turned out the airbox mount wasn't secured properly allowing it to rattle. Pushed it back in place and the vibration went away.

SubwayVQ

Yeah that is not the timing chain. You have a deeper thud. It almost sounds like a spun rod, but clearly that is not the case since it runs fine after starting.

thenewguyy

This rattler us happening only when switching gears as well as startup, basically anytime theres stress on the engine. So mainly on startups, when putting into drive/reverse from park. When im on the move, nothing, i do hear a few noises when travelling over bumps but thats cause im fairly low.
Ive had a new mount put in on the passenger side and people are saying most likely your transmission mount is the culprit since its the driver side mount and if the passenger one went bad, most likely the driver one as well as the others are bad or close to it.

Turbobink

iTrader: (2)

Agreed that it doesn't sound like a timing chain issue.

As you've already planned, check into the motor mount(s).

Also, if possible, see if you can get up close the full length of your exhaust system (i.e. car in the air) and check for wobble and contact between pipe/exhaust component and under-body.

Derrick2k2SE

iTrader: (3)

Ok, I misread your OP and thought you replaced the lower engine mounts.
Look at the two mounts on the cradle under the engine. Big round ones. My money is on the rear one being bad. That one goes bad either from oil or stress and really bangs around. It'll give a good clunk when getting on and off the gas too. Leaks from the valve cover or high pressure PS hose will kill it. If it's covered in oil you'll want to address that FIRST.

rodent_infested_03

Could be a transmission mount. I would also look closely at the exhaust. My other rig, an Escalade tormented me for months figuring out where the rattle was coming from. Turned out to be broken catalyst rattling around inside the pipe at certain speeds.

Why did you change the motor mount(s)? This issue?

thenewguyy

Will do, I have others saying its my transmission on thats bad which is the driver side mount.

I changed just the passenger side since I was having some vibration issues after putting in new axles. Turns out the axles didnt have the dampener which were causing the shaking. I changed the mount as well since it looked past its age but its possible the other mounts are probably close to or heading out fairly soon. Me being lowered doesnt help due to extra stress on them.