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X2 on the advice on the fuel. If a lower octane fuel is used in an engine that requires premium fuel, then you may get the knock, also referred to as pinging. Modern cars have a "knock sensor" that will retard the spark if this situation arises, but I am not sure if our mid '80's cars have a knock sensor. But using a higher octane than required is harmless, and will not cause a knock.

X2 on the advice on the oil as well. If the same weight range is used, it does not matter if it is dino or synthetic.

Could it be that the premium fuel you used had some sort of detergent in it that cleaned out something or other so you now are hearing a noise that was not there before? Anyone care to chime in on that idea?

Bob
 

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As for the 5w-30, during summer, its exactly (or almost nearly) identical to 10w-30, as well as straight 30 weight oil, that "w" you see is what the oil looks like to your engine when its near freezing temps. This helps the engine crank easier in winter and allows the engine to warm up slightly faster as it starts to thicken with the engine's rising temps. This is also why, when its cold, one should allow the engine to idle for a few minutes before taking off with a cold engine.
 

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10W40 is mostly what is used from people on this forum for the 5M.
 
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You could try a 10W40 oil and see if that helps out at all. The oil will thin significantly as the engine warms - is the knock only when hot or cold? Did you check the oil level?
 

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but I am not sure if our mid '80's cars have a knock sensor.
The '85 has a knock sensor for sure, not sure if the older ones did, and since the OP has an '85, there should be one installed and working on his engine, so engine knock is not what this is. As well, even though 5w-30 is a bit thin for what he has in that engine right now, this is probably not what's causing the noise. I'd say to the OP that he should take into account the temps he is experiencing wherever he's at (doesn't say in his bio), look at the chart I posted from the Toyota TSRM and replace the oil with the correct weight if necessary, but don't expect the noise to go away.

The key thing here is that it sounds like its either the tensioner bearing starting to go, or perhaps the timing belt tensioner is loose inside too, but it could also be a slight exhaust leak at the manifold. Its really simple to start eliminating these issues with zero cost and an hour or less under the hood. Like I said earlier, pull the 3 belts off the front, start it up, see if noise goes away. If it does, you know its whatever is connected via belts. Install one at a a time, check to see which one brings the noise back. If the noise does NOT go away with all 3 belts off the engine. And before you even do that, you can get a hose, stick one side in your ear, use the other side to listen around the engine to pinpoint the noise, checking around the exhaust manifold and the belt tensioner, as well as the fan, the fan's shroud and anywhere else you think the noise might be coming from.

Because there's no check engine light, reason by deduction is your only choice to figure out what's wrong. Throwing parts at it and hoping that fixes it is just a waste of money and time, and that includes unnecessarily changing the oil for the moment. Find the problem, fix that, then determine what to do with your oil. If your car is completely stock, your ambient temps aren't over 100º and you don't drive it like a lunatic, that synthetic 30 weight oil you already have in there should be just fine for the next 3,000 miles. Remember, depending on where you're at, it should be getting cooler in a month or so, sooner if you're up north somewhere.
 

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Discussion Starter · #28 ·
Got 10w40 put into her, also put some Lucas Oil Additive into her, also thew some gas treat into her, we’ll definitely see what’s going on sooner than later, it was pretty hot these last few days 90+ Fahrenheit with really cool temps in the night 60 or so Fahrenheit. It might be a collection of all those problems but I’ll get it figured out one step at a time.
 

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X2 on the advice on the fuel. If a lower octane fuel is used in an engine that requires premium fuel, then you may get the knock, also referred to as pinging. Modern cars have a "knock sensor" that will retard the spark if this situation arises, but I am not sure if our mid '80's cars have a knock sensor. But using a higher octane than required is harmless, and will not cause a knock.
Bob
x3. Pinging or detonation or pre-ignition isn't going to happen while it's sitting there idling like that video. It happens during acceleration under load. The '85 (and newer) does have a knock sensor and when it detects pinging it will temproarily retard the spark to help reduce the pinging. One way to test your knock sensor is to tap on the block with a ballpeen hammer while it's idling. You will actually see/hear the engine idle RPMs go down if the knock sensor is workng correctly.
 

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Discussion Starter · #32 ·
UPDATE: Going to replace my valve lifters, and all the gaskets. Its not too pricey, only around 200 USD, parts list attached, any recommendations are accepted! already ordered a Camshaft Gasket Set.
Product Rectangle Font Parallel Screenshot


Font Rectangle Parallel Screenshot Number
 

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Stop throwing parts at it until you have it diagnosed. Get a long screw driver and place it on each part of the engine to narrow down the location of the knock. Put your ear to the other end.
Place it above each cylinder on intake then exhaust side
Place it on the front of the water-pump housing, power steering pump, alternator and see if there is any bearing noise there. Then listen to your exhaust manifold. See if you have a loose nut on there. Those have been known to back themselves off.
Or buy a mechanics stethoscope:

You can also use a rubber tube to listen, like a piece of heater hose. Place it on each area in turn and put your ear on the other end.

Diagnose, don't just open your wallet and start guessing. Too much of that going on on modern hard to figure out newer cars. These are way simpler.

EDIT: clarified what to do with the screw driver and tube
 

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I tried to tell the OP not to throw parts at it, that's just a waste of time and money and rarely solves the main issue. The problem is that most folks would rather not diagnose the problem but just hope they replace what may be broken or failed, @GmFaux02 , you gotta stop doing that or you'll run yourself broke and end up hating the car because its costing you too much!

Lots of good tips to help you diagnose the problem here, try using them to find the root cause then go from there.
 

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Discussion Starter · #36 ·
I tried to tell the OP not to throw parts at it, that's just a waste of time and money and rarely solves the main issue. The problem is that most folks would rather not diagnose the problem but just hope they replace what may be broken or failed, @GmFaux02 , you gotta stop doing that or you'll run yourself broke and end up hating the car because its costing you too much!

Lots of good tips to help you diagnose the problem here, try using them to find the root cause then go from there.
I diagnosed the problem, it’s the fing timing belt! Thankfully I haven’t ordered those parts just yet! It’s the timing belt! Of course it’s so stupid yet so simple, I recently changed all the belts EXCEPT the timing belt! And the other belts (fan/power steering, serpentine, ac) we’re in horrendous condition I should’ve just replaced all the belts then and there! Anyway I took it to a shop here that works exclusively on Toyotas and they said that yep it’s the timing belt, so that’s awesome.
 
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