Cylinder wall scoring

[BigBlueSince82]

I was changing my spark plugs today and decided to stick my borescope in my engine and did not like what I saw on 2 of the 3 cylinders on the right side of the engine. I didn’t even bother to change the other 3 spark plugs after seeing this. The engine does not burn any oil and the oil is changed every 5k miles and I drive 25k miles a year. The car now has 93k miles on it and I’m starting to get worried. Has any one else done this and can they post pictures for comparison.

 

[rdruss]

Looks like scoring from carbon build up around top of piston as it is short scores not length of cylinder. I wouldn't be too concerned. If you are maintaining your air intake system and changing your oil regularly there's not much more you can do. If you have no oil consumption that concerns you then don't worry, "keep on truck'n"!

 

[BigBlueSince82]

Looks like scoring from carbon build up around top of piston as it is short scores not length of cylinder. I wouldn't be too concerned. If you are maintaining your air intake system and changing your oil regularly there's not much more you can do. If you have no oil consumption that concerns you then don't worry, "keep on truck'n"!

Interesting you say that, I just ran BBK fuel system cleaner a few hundred miles ago. Do you think that could cause that?

 

[BlackWorksInc]

I almost wonder if they're even that deep to be honest with you. I have seen similar marks on other engines with higher miles and they didn't really register with a finger nail (a couple actually ended up being weird carbon tracking that had adhered to the walls).

But likely just some light scoring from carbon, it's not something I would be particularly concerned about unless you had other symptoms like low compression or oil consumption.

It's times like this I really wish I had taken and kept pictures of some of the 2AR-FE engines I cracked open for the oil consumption recall a while back. Some of those 150k+ and 200k+ engines still had factory cross hatching on the cylinders with very minimal scoring.

 

[Jeremy556]

Can't tell how deep they are from the camera, so no use worrying about them unless or until you develop further symptoms. I don't think there's anything you can do on this motor besides replace the block, anyway. Replace the rest of the spark plugs and (try to) forgettaboutit.

 

[octanejunkie]

Did you do a compression/leak down test?

This looks like nothing to worry about until you do.

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[BigBlueSince82]

Did you do a compression/leak down test?

This looks like nothing to worry about until you do.

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Not yet, that is my next step. I just replaced the last 3 spark plugs and I found more of the same maybe worse on the other cylinder walls! I will post pictures later today.

 

[Bmnorm2]

You can still see the cross-hatches in the scoring area. That suggests the scoring is still superficial. The scoring also appears to only be at the very top of the cylinder and does not continue down to where the peak pressure area for the compression ring is.

Hard to tell, but it looks like your piston is completely covered in coke (burnt oil)... You may be leaking at the valve seals.

 

[BigBlueSince82]

Here are the additional photos of the left side of the engines cylinder walls. Kinda speechless. Definitely did not to expect to see this amount of scoring. I looked at my 4 cylinder Ford Fusion for comparison which has almost 30k more miles then my 4Runner and it has absolutely no scoring on any cylinder walls. I even have a picture of my oil level on my dipstick after 2500 miles. Shows a perfect reading. Not sure what is happening!!!!

 

[Bmnorm2]

The first picture.. is the right side the Top of the cylinder (valves?) It literally looks like oil regularly leaking down from the valve seat. Run that leak down! I think you are leaking oil from valve seat and it's burning into hard carbon and scoring the wall.

 

[Charles Bronson]

Given that the motor isn't given you any trouble, runs fine, isn't throwing codes, and isn't burning oil, I wouldn't be too concerned. If you're really worried, run a compression test. Sometimes things on these scopes can look worse than they appear.

 

[03_4x4Runner]

What oil and filter are you using?

 

[T4R2014]

Just pretend you never saw it. I doubt you can even feel that with a finger nail.

 

[lewdog998]

Just pretend you never saw it. I doubt you can even feel that with a finger nail.

He cannot unsee it now....its like having cancer, if you never go to the doctor you will live forever. Once you go they find something and you only have 6 months to live.

That engine is toast and will blow at any moment...do I hear a slight rod knock......OP i will give you 5k cash (small unmarked bills) right now.

 

[Whippersnapper02]

Give it the old Italian tune up.

 

[BigBlueSince82]

You are probably right but I didn’t buy a 4Runner to start to have doubts at 90k miles. Really pisses me off. I I’ll be doing a compression test by this weekend to rule out other possibilities.

 

[BigBlueSince82]

What oil and filter are you using?

Quaker state full synthetic with trd oil filter.

 

[BlackWorksInc]

[MENTION=282873]BigBlueSince82[/MENTION]

I had the spark plug out of this 2003 Highlander with a 3.0L 1MZ-FE engine earlier today, so I snapped a quick picture with my scope (I also see that I need to fix the date and time on it...) It has over 230k on it and mechanically runs very well with no significant oil consumption or mechanical issues (though this poor thing needed a lot of maintenance from being neglected); here's what the inside of the cylinder looks like.

It's not exactly an apples to apples comparison given the 1MZ-FE is a cast iron block, but it uses roughly the same hardening process as the cast iron sleeves in your 1GR-FE block IIRC, so close enough.

Note- I didn't bother rotating the picture, so up is down, down is up.

 

[octanejunkie]

[MENTION=282873]BigBlueSince82[/MENTION]

I had the spark plug out of this 2003 Highlander with a 3.0L 1MZ-FE engine earlier today, so I snapped a quick picture with my scope (I also see that I need to fix the date and time on it...) It has over 230k on it and mechanically runs very well with no significant oil consumption or mechanical issues (though this poor thing needed a lot of maintenance from being neglected); here's what the inside of the cylinder looks like.

It's not exactly an apples to apples comparison given the 1MZ-FE is a cast iron block, but it uses roughly the same hardening process as the cast iron sleeves in your 1GR-FE block IIRC, so close enough.

Note- I didn't bother rotating the picture, so up is down, down is up.

Par for the course with a waste spark ignition system, aka nothing to be concerned about. The sooty buildup on the piston face will increase compression over time lol

Cross hatching on the cylinder walls is normal, from the factory to promote ring seal and proper break in, and over time as the rings rotate in the piston grooves.

If your cylinder walls are not chrome lined (ours are not) and they are smooth as silk, then be worried.

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[BigBlueSince82]

[MENTION=282873]BigBlueSince82[/MENTION]

I had the spark plug out of this 2003 Highlander with a 3.0L 1MZ-FE engine earlier today, so I snapped a quick picture with my scope (I also see that I need to fix the date and time on it...) It has over 230k on it and mechanically runs very well with no significant oil consumption or mechanical issues (though this poor thing needed a lot of maintenance from being neglected); here's what the inside of the cylinder looks like.

It's not exactly an apples to apples comparison given the 1MZ-FE is a cast iron block, but it uses roughly the same hardening process as the cast iron sleeves in your 1GR-FE block IIRC, so close enough.

Note- I didn't bother rotating the picture, so up is down, down is up.

Thank you, i appreciate the effort. I hope others can share photos for comparison. I’m starting to really lean towards the valve seats leaking. Either way after 90k plus miles I don’t believe there shouldn’t be vertical score lines like this in an engine that doesn’t have future problems on its way.