3RZ Engine Tick

[Pyral]

My 3rz has a noticeable engine tick. The ticking happens at all RPMs whether my engine is warm or cold. The fact the engine was cold in this video doesn't matter at all, it would sound the same if it had fully warmed up.

(Link if this is broken)

I shot a video from inside the cabin of the engine sound. I usually drive more leisurely and smoothly than how I did in the video, but I wanted the full range of gears that I could get in a short time. I'll try to make another one from the engine bay later on. The ticking is most noticeable 27 seconds into the video after I made that sloppy shift.

I've had this ticking for a while, but I didn't think much of it until I heard another 3rz without such a pronounced tick.

I know that the 3rz-fe suffers from valve clearance issues. They can make a ticking noise if they get too loose. But I can't find a video of what that sounds like.

 

[FD7683]

My first action would be to pull off the valve covers and perform a quick valve adjustment.

 

[JZiggy]

+1

Sounds like valves need adjusted. Timmy and I did a video on it. Let me know if you need some help… it’s not too hard once you get your head around it.

 

[Pyral]

I understand the idea behind it. From what I understand having the valves too loose isn't destructive in most cases (it would have to be really extreme), it will mainly decrease power and efficiency.


I might wait a month or two because my current schedule is too busy to have my only car out of commission waiting for a shim.

How do you check the timing chain tensioners while you do this job? It was mentioned in timmy's video, and I would like to know how much life there is on it.

 

[jth32199]

So I have a 3rz and been getting through the noises it makes. I was getting a ticking and it sounded like it was coming from the motor but it ended up being an exhaust leak which is easy enough to find. The 3rz's with the cast exhaust manifold are known to crack and have a leak. Also I had a clicking/ticking noise and it turned out to be the u joint closest to the transmission/transfer case.

Do you here it coming from the passenger side of the vehicle? Does it happen on when you're moving or both when you're moving and parked?

It could also be a U joint going out or in need of some grease. Let me know!!

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[Pyral]

I recently got all the zerks greased for an unrelated rotational squeak that I was having(which didn't fix it). So my u joints are all looked after, and they showed signs that the previous owners also greased everything regularly too.

A manifold leak is possible, but very unlikely. My whole exhaust system is crusty, but my car passed CA smog in 2020, they would of been all over me if there was some sort of leak. And the tick was present even then, luckily it didn't keep me from passing.

The noise is present even at idle.

 

[JZiggy]

If it's a cracked exhaust manifold (which does happen on the 3RZ) the sound will be very clearly load-dependent. Valvetrain noise is usually just RPM dependent.

 

[jth32199]

If it's a cracked exhaust manifold (which does happen on the 3RZ) the sound will be very clearly load-dependent. Valvetrain noise is usually just RPM dependent.

You know what, you're completely right. I know the 3rz's have to get valve adjustments more frequently than the 5vz.

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[jth32199]

I recently got all the zerks greased for an unrelated rotational squeak that I was having(which didn't fix it). So my u joints are all looked after, and they showed signs that the previous owners also greased everything regularly too.



A manifold leak is possible, but very unlikely. My whole exhaust system is crusty, but my car passed CA smog in 2020, they would of been all over me if there was some sort of leak. And the tick was present even then, luckily it didn't keep me from passing.



The noise is present even at idle.

I gotcha, mine passed smog here in Comiefornia twice, maybe I got lucky [emoji28]

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[davidch]

I would suggest exhaust leak. I own two (his and hers) 3RZ-FE 4Runners. One had a cracked exhaust manifold at 120k.

Cracked headers are not an uncommon issue with this engine. Apparently, Mighty Toyota itself determined the cast manifold had problems, as later Tacomas had a header-style manifold. See posts here:

any good source for a 1999 tacoma exhaust manifold? | Tacoma World

Assuming you can get the 2 nuts and 2 bolts off the manifold shield, it's quick and easy to check.

In my experience with 5 such engines - others will disagree - these engines exclusively suffer decreasing valve train lash, which doesn't lead to a ticking noise.

 

[JZiggy]

I would suggest exhaust leak. I own two (his and hers) 3RZ-FE 4Runners. One had a cracked exhaust manifold at 120k.

Cracked headers are not an uncommon issue with this engine. Apparently, Mighty Toyota itself determined the cast manifold had problems, as later Tacomas had a header-style manifold. See posts here:

any good source for a 1999 tacoma exhaust manifold? | Tacoma World

Assuming you can get the 2 nuts and 2 bolts off the manifold shield, it's quick and easy to check.

In my experience with 5 such engines - others will disagree - these engines exclusively suffer decreasing valve train lash, which doesn't lead to a ticking noise.

The header is a great upgrade. Timmy did a video on that too using my truck.

You are correct on valve lash. They tighten.

 

[Pyral]

The only thing I can think is that the previous long time owner intentionally set the valves loose so they could have more time between adjustments. I talked to a Toyota mechanic who said the same thing about the valve clearences getting tighter not looser. I'll probably get the valves done no matter what sense I don't know when they were done.

I shot a video from the engine bay today. At idle the tick was hard to decern, especially through video. And it does become more apparent under load. I thought exhaust leaks typically made the vehicle louder. If its not the valves its probably a cracked manifold.

 

[Pyral]

I got a video in the engine bay. It isn't going to be very helpful because my phone did a poor job of picking up on the sound. Make sure your sound is down, I didn't realize I had the phone mic pointed in a draft created by the engine for a part of the video.

I think the engine ticks more under load then at idle so that might be the reason it isn't as apparent in this video.

I'll try to remove the shield, but there is a good chance the bolts wont come loose without more violent extraction methods. My vehicle is a 49 state vehicle, so I would think that it would already be at a disadvantage when it went through CA smog.

 

[Pyral]

Could this be the culprit?

I got around to removing the exhaust manifold heat shield, to anyone reading this in the future removing the bolts for the shield is a lot easier than you might expect, even if they are rusty like mine were.

I found what I believe to be a hairline crack between cylinder 2 and 3.

Photo 1(as close up as I could get)

Photo 2(more complete photo of the crack)

Photo 3(close up of crack from different angle)

Photo 4(zoomed out to provide orientation in engine bay)

Link to complete album

Is this a large enough crack to be the source of my engine tick?

 

[heat]

I'm seeing evidence of exhaust gas staining the metal, which
is, yeah, you'll probably hear it. Gotta be changed out anyway,
won't fix itself

Also looks to me like there might be a second crack in photo 1,
north of the first one.

 

[JZiggy]

I got around to removing the exhaust manifold heat shield, to anyone reading this in the future removing the bolts for the shield is a lot easier than you might expect, even if they are rusty like mine were.

I found what I believe to be a hairline crack between cylinder 2 and 3.

Photo 1 (as close up as I could get)
Photo 2 (more complete photo of the crack)
Photo 3 (close up of crack from different angle)
Photo 4 (zoomed out to provide orientation in engine bay)

Link to complete album

Is this a large enough crack to be the source of my engine tick?

The 3RZ engines are known for cracked exhaust manifolds. Mine was replaced by the dealer and PO when it had ~150k on it. I proactively replaced that one with the OEM mini-header which has been working great for years now.

That crack will definitely be audible.

 

[Pyral]

Here is a video of the exhaust leak. Now to replace the manifold. I've read that this fix can have a small improvement in power, is that true?

Do I have to replace the heat shield when I fit the miniheader or can I reuse the old one even though its larger?

 

[JZiggy]

Here is a video of the exhaust leak. Now to replace the manifold. I've read that this fix can have a small improvement in power, is that true?

Do I have to replace the heat shield when I fit the miniheader or can I reuse the old one even though its larger?

The miniheader heat shield is different. You can:

- Buy a new OEM one
- Hack your old one to fit
- Run without, probably not a big deal (though I'm too OCD to do it that way)

Hopefully you found Timmy's video where we did this mod?

 

[Pyral]

Yep, I've seen the video Timmy did for this issue. I'm using the part numbers from it. From a cursory search that manifold (17141-75080) costs $254 from camelback Toyota. The manifold and heatshield are far from the only parts that will need to be purchased.