mc1114

New to the forum. Just purchased an 07 automatic with 152k miles on it. Nice little car. Excellent condition and cheap, so I decided to overlook the fact that it has a noise.
I'm also in the auto repair field so I do my own work and parts come cheap. Anyway the sound is very similar to this (not my car):


Its not the typical valve sound but the distinct tap/knock that you start to hear around 4 seconds into the video. In my car it sounds louder around the rear of the head (cylinders 3 and 4). Does not go away when warm, and it only happens under load, whether its driving or at idle. If I go up and down on the gas pedal, it can be heard when the RPM's rise, and not heard as they're dropping again

I was wondering if there's a certain area in these engines thats common to make this type of sound or what are the common engine issues these cars have. Most of what I've found from searching involves rod knock, but this sounds more like piston slap. This is not my daily driver but when I get a chance Im gonna remove the valve cover and see if there's anything obvious making noise. I've also changed the oil with 10w30 but that didnt help

As I said Im not too concerned with it because I know from being in this field, noises can sometimes last a long time before they affect driveability, but I'd still like to pinpoint it

And in case for future reference, what years/makes/models of the 2.4 Toyota engine would be a direct, easy fit in the 07 tC?

Thanks in advance

DeAnzaJig

Pop the valve cover off and check the valve lash between the lobe and bucket. also rotate the crank by hand and watch the valvetrain and see if everythings moving smoothly.

And any 2AZ-FE engine will bolt up if your looking for a swap. Mostly found in:

2002–2009 Toyota Camry
2002–2008 Toyota Solara
2004–2008 Toyota RAV4
2005–2007 Toyota Highlander
2005–2010 Scion tC (first Gen)
2008–2012 Scion xB (Second Gen)

and even a few others that i cant think of at the moment

mc1114

After cutting spark to each cylinder, we determined that cylinder #4 is the cause of the noise. I also learned valve adjustment on this engine is a lot more involved and complicated

No obvious problems and no significant amount of clearance between the lobe and bucket. However I didnt have any specs and didnt check to make sure the engine was at TDC (was on a time crunch), but I made sure the rounded part of each lobe was pointing straight down on cylinder 4 when checking. Should I do it over, this time comparing specs? The lobes on the camshaft showed no significant signs of wear

If the noise was valvetrain related, would it only happen under load, or all the time?

And a non-engine related question to anyone that might know - I have the common climate control without lights issue. Would 05, 06, 08 climate controls work on the 07?

mc1114

Are all the 2AZ's from the years posted above, identical internally?

I know about the differences externally. Timing covers, motor mounts, etc. For future reference I'd like to know what I can drop in there. I read there are two different versions of the 2.4 with the later version having a different cam and pistons (I think).

Can anyone provide some insight? If I ever throw in an engine, I dont want to worry about ECM tuning issues. Just want to change the external stuff, move harnesses around, and thats it

That_Kid_Ju

For the tc, 05-06 pistons don't have oil squirters. 07-10 do, I believe. Best bet is to get a motor for your model and year to be on the safe side.

DeAnzaJig

They both have oil passages, but the 07+ sprays from the block, as opposed to having it sprayed from the rod. The block method seems more efficient, but i have seen no difference in wear between the two. Also the balance shafts and head studs are a bit different also. But again, ive seen no difference in efficiency, or reliability between the two. Swapping any motor, as long as its a 2AZ-FE, excluding any other AZ family motor (1AZ-FE, 2AZ-FXE etc...) you will have no problem.

And for the lash, the buckets are non-hydraulic and not adjustable. The only way to "adjust" lash is by putting in a bucket with a different clearance. on the underneath of the bucket will have a reference number for what size it is. I dont know the specs off hand but i will post them for you tomorrow when i get off work. and you dont have to have the lobe your measuring exactly at TDC, as long as the intake lobe is just past the intake stroke, or on compression, just so the exhaust lobe is nearly pointing straight up if your measuring the exhaust lobes, and vise versa with the intake lobes.

Ill post both the inner and outer diameter of the cam lobes, and specs tomorrow

But i listened to the video again, this time with better headphones, and it sounds a bit like wrist pit bore clatter, but usually that stops under load. But before jumping to any conclusions, lets start with the basics. Pull out the plugs, and check the condition, do a compression and leakdown. And if you really want to have fun, pull the oil pan off, drop the oil pump and balance shafts, and take a good look at the rods if you can't find any other cause.

Also one other question, who did you buy the car from? was he older or younger? and did he say he ever modded it?? I only ask this because ive seen about a billion tc's come into our shop and have internal motor problems that happened shortly after they bought it. and usually the customer bought the car from someone younger. Sometimes its really hard to tell if someone ever touched it besides maintenance or wear items, people can hide their work pretty good if they know what their doing.

mc1114

Thanks for all your posts guys

DeAnza - the plugs look like they have just been changed. As for tearing stuff apart, I dont think Im going to mess with it anymore until it starts to affect driveability, but I do want to do a compression test since thats easy. But if things get worse I'll just throw in a used motor. Already took a quick glance at prices and they're not that bad. The would be no labor involved since I would be doing the work at my shop

As for who owned it, I bought it off a early 20s female who seemed pretty meticulous about maintenance, although I have a good feeling she probably accelerated hard on a regular basis since she mentioned once or twice how "fast" it is. Its also had one owner before her. What made me purchase the car is how clean it is, the big sunroof :D, the fact that its completely stock, transmission shifts great, not a single drop of oil or leaks underneath, priced much lower than most I've seen, and that it has a clean title. Seems 95% of TC's out there are salvaged, and this is important to me as Im not one that keeps cars for years or until wheels fall off. I dont see lack of maintenance being part of this car's history

I actually really like the car and as I said, not too worried about the noise for now. But in case I keep it long enough and the time comes to swap an engine, I'll want to start the work immediately

Im actually surprised that this engine often doesnt make it to 200k, or even 150k without internal problems. I've read numerous stories about blown 2AZ's. Not just in Scions but in other Toyotas as well, driven by the older crowd

The only noise bugging me right now is a squeaking/chirping at idle that is coming from the passenger side engine mount. Not even the radio can muffle it lol, and its driving me nuts. That will be getting changed soon

DeAnzaJig

Do you have access to a scope? I would also scope the primary ign, just to see if anything weird is happening in the cylinder

mc1114

I do not

Is it fair to say, since the noise is only heard under load, that its most likely coming from the bottom end?

Im thinking if it were valvetrain related, it would be heard all the time

DeAnzaJig

yea usually the 2 noises heard under load are rod knock and crankshaft end play, ive never actually heard piston slap in person, and also excessive pin bore clearance usually happens during engine decel

mc1114

Well, nothing to worry about for now. lol. Its just gonna keep being driven

mattchuetc

it sounds like maybe the oil pump could be going bad when its under load it may not be getting enough oil up there and is y its not so loud at idle