Grind sound on Cold start

[japes]

Doing cold start (37C outside temp. Normal for heat wave this time of year) last 2 days the car makes a brief grinding noise that is very similar to this [ame="https://www.youtube.com/watch?v=aafLiPygXhM"]2010 Corolla start up noise 2 - YouTube[/ame] .

The first time, I thought it was when I let go of the clutch but it happened again and I already had the clutch out. It happens about a half second after startup, and lasts for a half second.

Car is a JDM 86, 2016 bought new at the end of Feb. Has 4k kms on it.

Any help?

[Ultramaroon]

Post a clip of your own car making the actual sound. Then maybe we can talk.

Or just leave it at the dealer until it cools off enough to show someone in person.

[humfrz]

Yep, a clip of your car starting would be good.

In the clip you posted, I just hear a starter motor and some valve tappet chatter.


humfrz

[japes]

Since that clip shows the exact sound and timing I thought it would be fine. The dealer will come and look at it. However language barrier in Japan is real, and im also aeay for the next 2 weeks. Thought it would be worth whilev trying to track down the cause

[Ultramaroon]

Originally Posted by japes

Since that clip shows the exact sound and timing I thought it would be fine. The dealer will come and look at it. However language barrier in Japan is real, and im also aeay for the next 2 weeks. Thought it would be worth whilev trying to track down the cause

Ok well, on that clip it sounds like all the oil is dumping back down to the pan so everything's dry on startup and it's taking a while for it to build up oil pressure.

Then I went and looked at the comments on the youtube post. A toyota tech nailed it.

We have a similar hydraulically controlled variable valve timing system which has a known failure mode in which a check valve falls apart releasing all oil pressure. This eventually causes crankshaft/rod bearing failure due to oil starvation.

[japes]

Originally Posted by Ultramaroon

Ok well, on that clip it sounds like all the oil is dumping back down to the pan so everything's dry on startup and it's taking a while for it to build up oil pressure.

Then I went and looked at the comments on the youtube post. A toyota tech nailed it.

We have a similar hydraulically controlled variable valve timing system which has a known failure mode in which a check valve falls apart releasing all oil pressure. This eventually causes crankshaft/rod bearing failure due to oil starvation.

Thanks. Do you think there is a TSB for it? I found the one for the corolla but no 86

[Ultramaroon]

Originally Posted by japes

Thanks. Do you think there is a TSB for it? I found the one for the corolla but no 86

There isn't one directly related to the mechanical failure but there is a more general TSB which combines it with other valve timing issues. It's the top stickied thread in this section.

http://www.ft86club.com/forums/showthread.php?t=15577

edit: mind you, I'm not making a call. I'm hypothesizing based on the clip you chose to describe your sound.

[Ashikabi]

Originally Posted by japes

Thanks. Do you think there is a TSB for it? I found the one for the corolla but no 86

Assuming we are talking about the vvti system failure related to "cam over advanced" and "cam sensor delay" codes stemming from the oil valve failure... Toyota does not have a TSB, Subaru does(or did). I just dealt with that issue. For me it was caused by a spun bearing but your problem could be unrelated. I don't know everything about engines and I didn't watch the clip since I didn't think I would be able to garner any info from it. Just saw the vvti mentioned and wanted to offer some info

[Ultramaroon]

Originally Posted by Ashikabi

Assuming we are talking about the vvti system failure related to "cam over advanced" and "cam sensor delay" codes stemming from the oil valve failure... Toyota does not have a TSB, Subaru does(or did). I just dealt with that issue. For me it was caused by a spun bearing but your problem could be unrelated. I don't know everything about engines and I didn't watch the clip since I didn't think I would be able to garner any info from it. Just saw the vvti mentioned and wanted to offer some info

Actually, your oil valve failure caused the spun bearing. That and the issue of over-applied sealant breaking off and clogging an orifice are the two things I sweat.

[Nickosport]

Originally Posted by Ultramaroon

Ok well, on that clip it sounds like all the oil is dumping back down to the pan so everything's dry on startup and it's taking a while for it to build up oil pressure.

Then I went and looked at the comments on the youtube post. A toyota tech nailed it.

We have a similar hydraulically controlled variable valve timing system which has a known failure mode in which a check valve falls apart releasing all oil pressure. This eventually causes crankshaft/rod bearing failure due to oil starvation.

This^^. 8th gen Honda Civic SI has the same issue, but Honda doesnt have a fix.
This should be covered under powertrain warranty. It should be pretty straight forward for a dealer to diagnose. I suggest you not drive it as a valve timing issue can bend valves and screw up pistons.

[Ashikabi]

Originally Posted by Ultramaroon

Actually, your oil valve failure caused the spun bearing. That and the issue of over-applied sealant breaking off and clogging an orifice are the two things I sweat.

I dunno, dealership said it was the other way around but I'm not sure how you would be able to tell

[Ultramaroon]

Originally Posted by Ashikabi

I dunno, dealership said it was the other way around but I'm not sure how you would be able to tell

Your dealer is full of shit. First, it's a widely known sequence of events that you unfortunately experienced. Second, there's no way a spun rod bearing would cause a peened cover to pop off of a valve timing control assembly.

[guybo]

There's no way to tell what the sound is from a recording of a different car. That sort of a sound could be a LOT of things and not all of them are catastrophic. Record YOUR actual car making the cold startup noise and get back to us.

I have a tendency to believe it's a loose heat shield and not a an oiling system issue with a brand new car. But that's a guess based on an internet video of one startup of a different car