Solved:Engine rattle at low RPM

[Dino451]

Hi I was wondering if anyone can help me. I am having a odd rattling sound coming from the passenger side at 1500-2500 RPM. After that I cannot hear it due to engine noise. It happens only when its warmed up and seems to be near the upper half of the engine. The dealer didn't do anything other than open a case with Toyota and MAY get back to me. The first time I took it they told me it was the fuel pump but I told them I know it's not because its been replaced already and it's on the opposite side. Second time they opened the case after letting them actually hear the sound since they thought it was all normal sounds. My engine has approximately 40K and have been hearing this for 3K miles. Video link below, sorry for the vertical video. Sound can be heard at the 2 second mark.

Video taken Christmas Day
[ame="https://www.youtube.com/watch?v=OFPW0OS2_5I"]FRS crankshaft bearing failure - YouTube[/ame]





I just got a call and the SA said they found a bad crank rod bearing? Ill get a better explanation later today. I think someone else on this forum had the same issue but my rattle sounded different from theirs.


Going to pick up the rental.


Edit:
I had a recent oil change(less than 500 miles ago) from the dealer and still can be heard.


Update:Update: 1/20/16 After I got it back in mid December I had it for two weeks before a even louder rattle appeared. I took it in the week after Christmas and it was diagnosed with a damaged crankshaft bearing.

Dealer said there was debris in the oil pick up and that they would order all new crankshaft bearings and that it might be ready end of the week last week.

Not sure what happened between that time but I was told yesterday I will be getting a new shortblock

Hopefully I will be getting my 86 back soon.

[chaoskaze]

you think too much, drive on? don't hear anything out of norm. O.o

[Ultramaroon]

I hear it. Could you get the dealer to check to see if your oil pressure is within spec, at normal operating temp, of course?

[Dino451]

Originally Posted by Ultramaroon

I hear it. Could you get the dealer to check to see if your oil pressure is within spec, at normal operating temp, of course?

I will have them check next time I go.

[Dino451]

Originally Posted by chaoskaze

you think too much, drive on? don't hear anything out of norm. O.o

It's at 2 sec after the AC compressor kicks in and again at about 9 sec. It tapers off after that. I have no CEL and nothing seems to be effected other than the sound/rattle.

[Ultramaroon]

Originally Posted by Dino451

I will have them check next time I go.

There's another thread in which I hear exactly what sounds like excessive valve lash which comes and goes. This is a common symptom of leaky/dirty hydraulic adjusters but the fa20 doesn't have those. I'm genuinely confused by the sound.

Realistic or misguided, just wanted to explain my thinking on the subject.

[Dino451]

I took another video of the noise which is very obvious now. It sounds like it's the port injectors but only between 1500-2500 RPM. Going to dealer next week because it's getting louder and its annoying. It's starting to make the noise now when cold and it does the startup fast revving to warm up the Cats.

Would bad injectors make this noise?

Edit: Also forgot to add that the whole car shakes slightly at that RPM range. Anything below or above that range its smooth as silk.

[Ultramaroon]

Port injectors are way too tiny to make that heavy of a sound. Whatever it is, it definitely needs attention.

Mine does the same little dance at that rpm under no load. I think it's a resonance of the engine-transmission in the mounts. No biggie. That's a really subtle one. Kudos for noticing it.

[Dino451]

Originally Posted by Ultramaroon

Port injectors are way too tiny to make that heavy of a sound. Whatever it is, it definitely needs attention.

Mine does the same little dance at that rpm under no load. I think it's a resonance of the engine-transmission in the mounts. No biggie. That's a really subtle one. Kudos for noticing it.

I was really hoping it was as simple as the injectors.

I guess I didn't want to admit it haha

[Dino451]

update:
They are going to open up the engine and check the valve train.

[acetothermus]

Originally Posted by Ultramaroon

Port injectors are way too tiny to make that heavy of a sound. Whatever it is, it definitely needs attention.

Mine does the same little dance at that rpm under no load. I think it's a resonance of the engine-transmission in the mounts. No biggie. That's a really subtle one. Kudos for noticing it.

It almost sounds like excessive valve noise. Wonder if the guides either wore out or were defective from the start.

[Ultramaroon]

Originally Posted by acetothermus

It almost sounds like excessive valve noise. Wonder if the guides either wore out or were defective from the start.

It does sound like valvetrain noise but I'm cutting back on my speculation. I was swinging like Tarzan on a another similar thread yesterday.

[Dino451]

Update: I just got a call and the SA said they found a bad crank rod bearing? Ill get a better explanation later today. I think someone else on this forum had the same issue but my rattle sounded different from theirs.


Going to pick up the rental.

[Dino451]

Crank Shaft bearing failure confirmed. Engine is in pieces.