Rattling from engine compartment.,,,

[ProDarwin]

Sounds almost like a tin can rattling. It was there before I pulled the motor, and I though it was the tensioner, so when the motor was out to install the manual, I replaced it. Anyways, the motor is back in now, and it is still making the same ugly rattling noise. Any suggestions?

[SLeepr]

ARe you sure it's not the cat? The only noise I can think of that sounds even close is when my catalytic converter pooped the bed.

[Marlin1975]

Take the belt off and start it up. If it still makes the noise then it is not anything that is run by a belt as in bad bering.

If the noise go's away then you have something spinnig that is bad.

[bbarbulo]

Ya, I get this UGLY noise... comes on only in Drive at a light, about 3-5 seconds after I fully stop. If I roll, there is no noise, or if I'm not stopped for an extended period there is no noise. I'm pretty sure this is recent too... but I think it's exhaust, and the engine mount working in unison to create a resonance throughout the car so everything shakes rattles and rolls

[skijay]

I had a problem last summer with the 97 SL2 auto. When the car was warming up and I would shift into gear, I would hear this vibration type rattle that I could not seem locate as it resonated inside the car. I at first thought it was the AT.

After a trip to the dealer, the rattle was traced to the driver's side headlight assembly. Apparantley there was a bolt that corroded and that was causing the rattle. They replaced the bolt and no more rattles.

[ProDarwin]

Doesn't sound like the cat. Sounds distinctly like it is coming from the right side of the engine compartment.

[bbarbulo]

perhaps the lower dogbone mount is in need of looking at? This rattle... can you be more specific... like someone said other things can rattle too, like my tail lights on my SL2 were soooo loose when I bought the car, and I though it was just the plastic body that rattled under heavy bass... turned out to be my tail lights. Check everything.

[simtech]

I had this noise. When I investigated it I found out my whole timing system had started to fly apart. The chain guides were completely gone, the chain tensioner was frozen in position, the crank gear was missing some teeth, the chain was stretched, and had I left it any longer the chain would have eaten a hole in the water jacket. Check your timing components.

[Applefool]

I get a similar ticking type of noise that only comes in when im between 2500-3000 RPM, after 3k rpm, my intake and exhaust noise either drown it out, or it goes away. I'm not sure but I think it may be some valve noise, or possibly some noisy fuel injectors?

[Applefool]

I forgot also to mention that the addition of the AEM CAI increased this ticking noise to a point of some annoyance when driving at low speeds -

[psybapunk]

same here, but I put in a hotshot...

I'm pretty sure its the EGR valve operating normally, but the metal intake amplifies the sound, causing annoyance...

[ProDarwin]

Anyway for me to test if it is the EGR?

[wolfman]

There is a BRACKET where the exhaust down pipe from the manifold to the cat connects to the lower transaxle/cradle attachment point. There "should" be a bolt/nut tightly holding the bracket plate to the bracket...any chance it's not?

[sps SOHC]

Originally posted by Applefool
I get a similar ticking type of noise that only comes in when im between 2500-3000 RPM, after 3k rpm, my intake and exhaust noise either drown it out, or it goes away. I'm not sure but I think it may be some valve noise, or possibly some noisy fuel injectors?

EXACTLY what is happening with my car. Only it occurs only under acceleration and not just cruising. I think it rattles from 2K-3K rpm. I don't know what the heck it is but its not valve noise cuz I don't get any noise at idle.

[ProDarwin]

Originally posted by wolfman
There is a BRACKET where the exhaust down pipe from the manifold to the cat connects to the lower transaxle/cradle attachment point. There "should" be a bolt/nut tightly holding the bracket plate to the bracket...any chance it's not?

Nope not the braket. I'm concerned that it is the timing chain tensioner. Maybe at 206k miles, its time I re-do my timing chain.

[SLeepr]

Yeah, a new timing set would be a good idea.

SPS SOHC, this is also a possibility for your situation.

[ProDarwin]

Wait. Now that my good mechanic friend has looked closer at it, he said it could be the bearings in the water pump going bad. The sound got much louder after I put on a new belt tensioner. Any thoughts?

[wolfman]

Remove the belt and turn the waterpump pulley by hand while trying to wobble the pulley in/out up/down on it shaft. It should turn smoothly and have VERY little or NO "wobble"

[myoung]

I got the cat thing too, and I thought it was something in the engine at first. It's really loud at idle in drive and on low rpm acceleration. Also very embarassing.

[sps SOHC]

Originally posted by SLeepr
Yeah, a new timing set would be a good idea.

SPS SOHC, this is also a possibility for your situation.

I don't think so. I think the mechanic is an ***** and doesn't know what he is doing. I think the noise is coming from the tens. pulley. The same mechanic put a new pulley in 12K miles ago so I don't know why it would need to be changed already. Also I was charged $40 extra the second time around for the same part. inflation??? I think not.