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At least he is filling his parts cannon with cheap bullets...
 
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At least he is filling his parts cannon with cheap bullets...
Cheap but not low quality from the looks of it.

This thread is a good reminder to wait for answers before getting ideas. At least he didn't order a bunch of parts unnecessarily.

I threw a bunch of parts at mine when I got it, but it also wasn't running due to rats chewing wires so I decided to go deep and rebuild/replace everything from the bottom up. Usually a gamble, fortunately Toyotas tend to be forgiving if they haven't been overheated or run dry.
 

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Well that's one I have never, ever seen. The belt retainer ring literally unwelded itself from the gear and stuck to the plastic it melted? At this point, I'd be looking at the camshaft, the bolts that holds the two gears on, and the back aluminum plate for any irregular signs. You'll be looking for a new set of timing gears now, as I would definitely not try to repair that one.
 

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Wow. Unusual.Glad you found the issue. Sounds like you had a coincidental action. Put High Octane gas in and next start the timing gear slips.

I've seen that before. I once pulled a spark plug to see how my 2.2 Turbo was running and the timing belt tensioner decided to slip as I tried to start it a moment later. Had me stumped for a couple of days. Crank and no start.

Also had another one something like that. It was a ring gear on a flywheel that twisted just enough to rub the case and make a gawd awe-full knocking racket. Thought I had spun a bearing. $100 for a fly wheel and and engine/trans re-and-re and it was fixed. Also happened on a re-start after adjusting a couple of things up top on the engine.

Coincidental timing ( pun intended )
 

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Wow. Unusual.Glad you found the issue. Sounds like you had a coincidental action. Put High Octane gas in and next start the timing gear slips.

I've seen that before. I once pulled a spark plug to see how my 2.2 Turbo was running and the timing belt tensioner decided to slip as I tried to start it a moment later. Had me stumped for a couple of days. Crank and no start.

Also had another one something like that. It was a ring gear on a flywheel that twisted just enough to rub the case and make a gawd awe-full knocking racket. Thought I had spun a bearing. $100 for a fly wheel and and engine/trans re-and-re and it was fixed. Also happened on a re-start after adjusting a couple of things up top on the engine.

Coincidental timing ( pun intended )
I ALWAYS keep one important rule in mind when diagnosing cars; never assume it's only one failure. Cars are complex and coincidences happen often.
 

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Hi, I have a MK2 Supra (1985) and I might have made a mistake. So long story short, I was going about my day and went to go and fill my tank up. Well I guess I must’ve used premium because I have an engine knock. I’m worried about what to do and if there’s anything I can do. Please help I don’t want to loose this car over something so stupid like this. Thank you anything helps! Video attached.

Video of the knock
My guess is you probably put the lowest octane gasoline. Premium doesn't cause the engine to knock, It's the opposite. You're better off with the 91 octane as it's better for your engine. It's all I've used on my cars, never the lower octane. one time my wife put the lowest grade and then the engine started pinging (not knocking) acceleration.
 

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Wow, that's really not correct at all. Not trying to be a jerk here, but spreading the myth of higher octane is better is quite wrong.

First, knocking is exactly the same as pinging, which is also known as detonation. Detonation occurs when gasses at the edge of the flame are ignited after the spark has already ignited the fuel mixture, and this extra fuel combustion causes "knock" as it slams the piston in a different cycle of the crank. This usually occurs because the engine's spark timing is too far advanced.
Octane is an additive to fuel and works to resist detonation. The higher the octane, the higher the resistance to detonation, nothing more, nothing less. The higher octane allows an engine to have a further-advanced timing, which will effectively create more power by getting the spark past the ignition delay which is where the extra power comes from. This also comes at a cost to lower rpms.
With an engine that one can manually adjust the timing, one can pull a few extra hp by advancing the timing and running higher octane. Adjusting the timing to the point of detonation, then backing it off slightly is how you extract this extra horsepower. ECU-controlled timing on newer vehicles automatically adjusts the timing this same way, using the knock sensors (along with all the other sensors) to create an ideal hp rating without going into detonation. So, unless you've advanced the timing on your engine, running higher octane really isn't better for your engine.

Lots of technical data sources out there to confirm my watered-down explanation, try searching for "pinging detonation knock" as well as reading up on the causes of detonation. Also look for articles about advancing timing for more power.
 

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I beleive that higher octane fuels have less/no ethanol, and less potential water content.
Just for that potential water content, having fuel sitting in tank for long time periods (mainly in winter months), increase the rust creation in the tank, and components inside of it.
With all people having rust issues on pump hanger, sock and filter contamination, fuel level sender malfunction, and the tank rusting inside-out, I beleive using the Premium have some advantage in preventing this to happen.
 

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Should be the same percentage of ethanol, its usually stated on the pumps how much is added to the fuel. Problem with using high octane fuel, the fuel is not purchased nearly as regularly as regular octane, so turnover is low for higher octane fuels at the pump. Less turnover usually means a bit more water in the underground tanks since its not pumped out as regularly as the other fuel.

Had a brand new tank on my old motorcycle, went to fill up at the non-ethanol pump in town, looked in the tank and found silt at the bottom. Kinda hard to not notice on a brand new white plastic tank! Never filled up at that place again, and just noticed they dug up the tanks about a month ago and the station is now shut down.
 

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The only High Octane fuel (or any fuel ) here in Toronto that does NOT have ethanol is Shell 91. That's what I run. It actually smells different.
My neighbor with the Harley runs it too. I freaked him out one day when he had his bike running and told him "Hey, you're running Shell 91 in your bike" I could smell it.
20 years ago I use to use Sunoco 94. That's what was in the tank when the car got parked for 12 years. Boy were the fuel pump plastics brittle on the original Toyota pump .
Do I need 91 octane in a 5MGE with 9.2 compression? Nope, but I like the fact there is no ethanol in it. Car runs nice on it too.
 

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You guys up north are lucky, we have to search for non-ethanol stations here! A few carry it, but most don't. Old bikes hate ethanol, as well as most gas-powered equipment (lawn mowers, tractors pressure washers, etc.), it eats up the rubber hoses quickly and the fuel turns green inside the carb bowls pretty damned quick. I have to fill 5 gallon cans so I can run my dirt bikes/quad/pressure washer/ride-on mower about twice a month.
 

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You guys up north are lucky, we have to search for non-ethanol stations here! A few carry it, but most don't. Old bikes hate ethanol, as well as most gas-powered equipment (lawn mowers, tractors pressure washers, etc.), it eats up the rubber hoses quickly and the fuel turns green inside the carb bowls pretty damned quick. I have to fill 5 gallon cans so I can run my dirt bikes/quad/pressure washer/ride-on mower about twice a month.
I live in central AZ and have Ethanol-free 87 available year-round. I think it's the market i'm in though, as a ton of older cars, motorcycles, and even farm equipment have been putting around since the beginning of time. I fill my gas cans with it as it's much more stable (less hygroscopic) than blended. Technically can get about 5% more power out of an engine with the same a/f, but i live at altitude so that point is basically moot.
 
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