99 Corolla Rattling On Startup - Corolland: the Toyota Corolla Forums

Well since im under the car, i figured id try and adress another annoying issue and see if there are any solutions best solved under here

When i start up the first time in the day, theres a dreadful inconsistent rattle that appears when the car is in drive.

Id best describe it as a marble in a tin can being shaken ferociously.

It'll go for about 5 seconds, dissapear for 3, go again for ten (not always of course)

Its never a constant rattle. It doesnt change with throttle. Just an annoying metal on metal noise.

As always, any help is very greatly appreciated

Could be a number of things.

- Exhaust heat shield that is loose or one of the bolts rusted off is pretty common.

- Could also be the serpentine belt tensioner - as they wear out, they rattle pretty obnoxiously.

- Worn exhaust donuts can also contribute to this noise. Most commonly worn out ones on the 8th gen are the conical seat one (held with spring bolts) that sits between the exhaust manifold and downpipe and the conventional donut that sits between the downpipe and catalytic converter.

- Worn or loose brackets (upstream O2 sensor, spring bolts mounting plate, etc.)

- Worn engine/transaxle mounts.

- Could be piston slap, hard to say without being right there

Also, depending on where the noise is there while the car is sitting still or rolling - there could be a number of other things that could factor in the noise. Mileage on the car, maintenance history, anything of note - modifications / replacement of the car's suspension, wheels, etc.

Well it goes away after about 30 seconds to a minute, so im assuming it may have something to do with fluid pressure maybe??

It sounds as if something is loose, but it cant be something as simple as a loose bolt.

The sound is audible in front of the driver, right around where the engine sits. Maybe a little lower, could even be under the driveshaft. Its difficult to tell exactly, but its certainly near the center of the vehicle.

Check engine is on for 02 emissions, and visibly 02 looks fine. Connections are good, nothing loose.

Also, the car consistently makes a notable "grumble(?)" sound when i am accelerating at speeds at and under 5mph, more apparent when AC is running. Had mechanic check belts, he said he made a "minor" adjustment. This helped the issue of very low squeek that occured sometimes.

I can describe it as, a sputter maybe?

Could this possibly be caused by dirty fuel injectors maybe?

These sounds may be connected, they may not.

All i know, is my nuerotisiscm for engine noises will probably be the death of me XI

If it is only on a cold startup - another common issue is the power steering pump low on fluid/and or needing a fluid change. Very commonly missed service item - I've seen cases where the oil was the original fill on some early 8th gen models.

Along with that - the power steering pump pulley can also loosen over time and rattle like crazy. A quick test is to remove the serpentine belt and run the car for very short time - less than a couple of minutes, to rule out any noise from the pulleys. If the noise goes away - then you know it is related to the pulleys in some manner. Noise doesn't change - then you have to expand your search.

Not sure what sort of "adjustment" you can do to an automatic belt tensioning system - other than replace the belt, lubricated a bad pulley (should really replace if the case, or the noise will just come back) or use a belt dressing (not recommended, as it eats the belt).

Fuel injectors, themselves, generally don't make that sort of noise - even if they are really clogged up. Could be a misfire though - dying fuel injector(s) could be causing a misfire. Same with weak ignition, dirty throttle body, vacuum leaks, etc.

First of all i would like to say i completely appreciate your input, and i never expected to find such knowledgeable people on an internet forum. You and dom seem like very intelligent people, and sharing that is a very commendable thing.

I will do all of these tests you are suggesting my next day off.

Ive noticed something else as well. If i steer all theway to one direction (louder on left) i will hear a smooth scraping sound. CV's look solid, and the sound isnt so much scratchy as it is a consistent flow.

To best describe the sound, i would say a consistent almost flowing, muffled by something. When a tube runs water muffled by a layer of drywall? No bumping, or rattling or deviation from the initial pitch.

Anyway! Not sure if its related, but worth noting.

That's a little weird with the turning behavior - scraping noise can be CV joint related - but this sounds more like something make contact with a rotating component. Could be the rotor touching something likes its splash shield or something simple as the car picked up a piece of debris from the road or even low on powersteering fluid. Could be a bad wheel bearing, though those make more of a groaning, grinding noise than a scraping/muffled rumbling noise.