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I also read that it could be a top piston ring that came apart and is going between cylinders (not sure how this would work but whatever) I’m going to throw that idea out the door because there is absolutely no weird “clanky, or knocking” noises. And I’m not 100% sure but if the belt skipped a tooth, wouldn’t it throw a code or have a hard start or run like garbage?
May or may not. Be mindful when going WOT, be ready to pull your foot out. If you feel the hesitation don’t keep your foot in it. I would also have you timing belt and tension inspected if you don’t know how to check it for wear and deflection.
 

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And I’m not 100% sure but if the belt skipped a tooth, wouldn’t it throw a code or have a hard start or run like garbage?
I would think it should, but I've seen a car NOT throw a code (on an na Audi V8). Bent valves, not plugs, no code, ran pretty well but a little off. I don't know what would happen with this motor in that situation. I've also seen a Lexus ES t-belt job done wrong and off a tooth or two - no damage, ran OK but a little off, no codes.
 

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To repeat - timing issues can bend valves, not plugs, except that once the engine starts coming apart the valve and piston bits can possibly bend the plugs.
I think the OP is getting Volvo OEM plugs soon, that may just solve it.
Bore scopes are about $40 on Amazon, might be worth getting look inside the engine ;)
 

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Only time I've seen something like this (presuming the correct plug) is when a belt skipped. Which is inline w/what paradox... is saying.

No way that plug was bent w/o mechanical interference. And not on multiple plugs. Wrong plug, or skipped belt. I am not an expert on these engines, but this is not complicated/unusual to basic design/function on other engines.
Timing belt issue will not bend/break or contact plugs. The valves open and close while running and the plug is in a fixed location. If the belt skips, it doesn't move the valves or spark plugs around. What would hit is valves hitting pistons by being open when the piston is at TDC.
I would definitely get a borescope in those cylinders and see if there are marks on the pistons, and/or pieces of something in the cylinder
 

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Look at all the knicks on the electrode. I am not a mechanic but would cast my lot with Island..V70 about the chipped off porcelain. And like Tech said, the piston cannot fit up in there to hit the plug. Imagine what the top of your piston looks like. A miniature Pong game going on in your cylinder(s).
 

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Something coming apart in the intake. Do these Volvos have plastic intake components? Had same problem with my 6 cylinder Mercedes. They are known for intake issues. This sounds familiar. How many miles on the Volvo? Agree, AC/Delco plugs are junk!
 

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Hi BillSC70:

I am wondering if the plugs are damaged from pre-ignition? The picture you posted looks like it an explosion happened in the cylinder when it shouldn't have. Which is why I am thinking pre-ignition problem. Have you changed where you purchased gas recently?

How's your vehicle running now?

Thanks!
IW
 

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Hey guys, so the car ran fine today and I even put it under a little stress with a pull. What I’m going to do is take your advice and purchase some OEM Volvo sparkplugs, gap them properly and see if that will fix my problem. I do realize now that after so many miles that the chap plugs may have weakened, but with it happening to the new plugs still stumps me. I’m no mechanic but what I’ve heard is that the wrong type of fuel may cause pre-detonation or spark knock wich could be a concern. I will be getting the new plugs on Monday and follow up. If the problem arises again between now and then I will pull the plug and take a picture of it “real-time”. Thanks guys. Not many fourms I’ve been part of have been this responsive. If I could I’d give this Page 5 stars
How is this working out?
Regarding the plugs you show in your picture, they look (IMO) like cheap plugs in general. Old or new. And I do not know if they are even spec'd for your specific engine. I would go back to stock (i.e. OEM spec) plugs. Cheapie Auto Zone parts counter plugs might be your problem. Also always gap your plugs yourself, do not trust that they gap is properly set when the parts guy (or Amazon driver) hands them to you.
 

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No, something is bending the electrodes on these plugs. That's why I asked how many miles on the vehicle. Carbon build up? I doubt the pistons are hitting the plugs but it would not be the first time!
 

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No, something is bending the electrodes on these plugs. That's why I asked how many miles on the vehicle. Carbon build up? I doubt the pistons are hitting the plugs but it would not be the first time!
It would be the first time, as it isn't possible.
 

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It would be the first time, as it isn't possible.
"First time?" Where have you been? In order to bend an electrode on a an installed sparkplug SOMETHING has had to bend it through force, i.e. hitting it. The clearance between TDC and the bottom of the spark plug should never be zero unless the main bearing on the con-rod is so far gone as to create a lot up play. You would know this as the engine would probably not run or would make a lot of noise. Carbon build up, although not usual today due to clean gasoline, can bend a plug if the oil has not been change very often. If the motor is in poor shape (as I suspect this one is, that's why I asked how many miles) it is possible for some contamination to be introduced via the intake valves into the combustion chamber and in turn, bend an electrode. As I stated in an earlier post, this happened in one of my MB cars. It is possible for a piston to hit a plug (carbon build up) however unlikely you would probably know it as stated...
 

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The only way a piston is hitting that plug is if it's being shot out of the engine block
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No way? Put the wrong plug in with a longer reach and see what happens..... for starters.
I didn't say it was likely but not impossible! From what you surmise evidently the electrodes on the AC/Delco plugs are bending on the compression stroke? Never happen! You could buy the cheapest Chinese spark plus ever and that would not happen. Something solid is bending the plugs the OP described.
 

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Those aren't the wrong plugs though.

I know something solid is bending them. It is not the piston though.
 

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What octane fuel are you using? Have you got the the plugs replaced yet? What was the ambient temperature outside when this happened? Are you tuned? What boost are you running?
 
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