First off I’m new here, I’ve been scouring the forums trying to find something relatively close to the problem I’m having but I haven’t found any definitive answers. First off it’s a 1993 Toyota pickup 22re 5 sod, I’m getting this knock noise around 2500rpms that goes up to about 3500 rpm’s before it stops, it happens on acceleration and when I’m maintaining the rpm’s at cruising speed. It sounds as if it’s on the top end of the block.

I’ve done all the basics, tune up, oil change, cap&rotor. Then I moved on to the valve adjustments. They were way off I adjusted them according to LC Engineerings write up and while it helped my idle tremendously it didn’t solve this knocking noise. I also checked the timing chain guides and they’re in place and functioning.

I even thought it had to be a rod knock, so I pulled the oil pan and checked all of the rod bearings and all of them looked dang near brand new, I checked the wrist pins and they seemed good as well. I’m just shy of pulling the head to see what’s going on from the top side but if anyone has any ideas or more suggestions I’d greatly appreciate it.

 

Welcome! How many miles on it? Does it clear up when up to temp?
pull one spark plug wire at a time to see if that will narrow it down to a certain cylinder.
Any excessive oil consumption?
how did you check the wrist pins? My experience with a cracked piston had oil cobsumption and the knock was constant, more of a thump, lesser when warmed up.
It might just be the common 22re piston rock.

 

it has about 195,xxx on it. It has been rebuilt before PO said it had been rebuilt at about 185,000 miles. Not sure how true that is.

it does not clear up when it is up to temp, it stays the same whether the engine is hot or cold,

I tried the spark plug trick and it did not single out any specific cylinder, to me it sounds like the noise is coming from cylinder number 4. After pulling the plugs and nothing changing I was led to believe my connecting rod bearings were bad, so I dropped the pan and checked them all and they were all tight, so I marked and pulled my caps anyways to check and most looked brand new. 🤷🏼‍♂️ So I would assume that isn’t the situation??

I pulled the valve cover and verified the guides are intact and in place and the slack is correct.

and when I pulled the caps off the rods i push the cylinder up into the block and you can grab the connecting rod and by pulling the piston up or down you can usually feel slop in the wrist pin if it is bad, this is just a quick generic check, I won’t be able to completely verify that unless I pull the rod completely, but that method has worked for me In the past

and it does consume a little oil but it has always had an oil leak around the oil pan so every couple of months it lost about 1/4 of a quart of oil so nothing too crazy.

 

Have you checked compression in all cylinders?

 

Sounds like piston slap to me. Mine does it, but just when cold. Similar # of miles, but never rebuilt. Mine is loudest with very light load on the engine. Under load, it doesn't make a sound. I've adjusted my driving style to avoid the RPM+loads that cause the noise.

From all that I've read, this is a know issue with the 22R engine, and I've not read anywhere about it resulting in a failure. That doesn't mean it won't fail, just that I've not seen it written up as the cause of any engine failure so far.

You could start pulling plug wires to determine what cylinder it is, but honestly, what would you do differently with that information?

 

Hey,

A video would also be helpful. It’s difficult to say how normal or abnormal what you’re describing is without a video, as context is everything here. A “knock noise” to one person could simply be the familiar, but comforting tempo of a healthy flat tappet over head cam timing chain engine. Comparatively, to more modern newer automobile engines with roller lifters and timing belts, the 22R engine is loud by nature on its very very best day even with the valves perfectly adjusted to specification and application (different camshaft profiles etc), a healthy timing chain and guides, good oil pressure, and oil volume. They are loud little motors. However, it’s also possible you do have a problem.

My 86 22RE makes descent noise no matter what. It’s loudest right when fired up and load is applied and quieter when warm, but still has a good tick/tock to it, everything is perfectly in spec (newer timing chain and guides, oil pump, valves in spec, and 178-180 compression in all four cylinders) and with low miles. I have no idea what your experience level is with these motors, but I can say that many newer/ish 22R owners start listening closer to their motor and thinking there’s issues, once they own one.. myself included. My 81 22R isn’t as loud as the 86, but it’s marginal and still louder than the 95. Go to YouTube and watch a few videos listening to the 22R/RE, see what you think. Then get back to us.

 

hey bud go back to my original post and at the bottom there is a video attached to the post describing the noise, I’ve got enough experience with the 22r/e’s to say I’m confident and comfortable it’s not an average knock lol. And yes I know they’re some noisy engines. Could it be piston slap? quite possibly but from what I’ve gathered through diagnosing it this week I believe it is in the valvetrain. For one the previous owner had the motor rebuilt at some point, and the valves were set horribly, I mean the worst I’ve ever seen in my experience. Some when they were supposed to be “free” when cylinder #1 is at TDC, were actually putting pressure on the tops of the valves. 🤯 and none of them were even remotely close to in spec… it did smooth out my idle tremendously though.. 🤷🏼‍♂️



my knock is not effected enough by removing a spark plug for me to notice anything which also makes me think it’s a valve(kinda like it would be “floating” from a loose valve spring??) It’s also consistently the same no matter if the engine is warm or cold. Which is why today I’ll be pulling the head to see what I can find on the deck of the head and block.

 

Ah, I missed the attachment without my glasses this morning.. In addition to guides, the tensioner can be a problem.

 

Alright to anyone still following this, sorry for the delay, I found multiple problems that were resulting in my knocking problem.

Long story short, if y’all remember I I checked the valve clearances to find the previous owner had some valves with no clearance. and others had drastic clearance I’m talking .025” of clearance on some of the exhaust valves 😬 so I knew the valves were probably toast I pulled the head, and sent it off to get a full rebuild, it wasn’t warped and it pressure tested fine but all of the valves and seats were wore out. Which is where part of that awful noise was coming from,

while I was pulling the head I saw my plugs #1&4 looked rich and then I noticed there was a pretty heavy carbon build up on top of cylinders 1&4, which wasn’t exactly a surprise because I knew it was running rich before I pulled the head. So I knew once I got the head back I would need to address the running rich issue(big ugly exhaust leak)

So I got the head back, installed it and everything went together perfectly followed the service manual to a T and it all went fairly smooth. Of course all new gaskets, plugs, wires, injectors, fluids, etc.

I cut the old exhaust off which originally was leaking at the manifold, the collector, and it had an awful adapter/flex pipe contraption where the catalytic converter used to be from the previous owner. Which isn’t required where I live but if you’ve got an exhaust leak that close to the O2 sensor…. You’ll have problems. Which I had. Anyways I got the exhaust all dialed in and it has been running great!

so it’s not a one problem fixed all type scenario, I had bad valves, and a gnarly exhaust leak that were causing me fueling issues etc. anyway hope this helps someone somewhere with similar issues.

Carbon build up on top of pistons, coolant is from tilting the head when I removed it, some still splashed out

Toasted valves with no shortage of carbon buildup.


Had the plenum cleaned at the machine shop. Came out lookin fancy!

Full head rebuild lookin pretty!

Installed and ready to get the rocker arms and all torqued down.

Crappy exhaust setup from the last owner. Only about 3” of that flex pipe was showing when I cut the pipe and pulled it I found out they had crammed all of that pipe clean down to the muffler 🤣 I cut a couple pieces tacked it all into place and tig welded it all together. It’s solid and complete now with no leaks.