Experience with bad piston rings?

[perseuss69]

Replaced spark plugs today on my IS250. Thought I may as well do a compression test. Turns out the compression is in a very bad state.

According to this: https://workshop-manuals.com/lexus/is_250_awd/v6-2.5l_(4gr-fse)/engine_cooling_and_exhaust/engine/tune-up_and_engine_performance_checks/compression_check/system_information/specifications/page_3035/?expand_article=1 , the compression should be 14 bar or more, with a minimum of 10 bar. None of my cylinders got near that.

1. cyl dry 8,5 wet 10
2. cyl dry 8,7 wet 9,8
3. cyl dry 7 wet 9
4. cyl dry 8,5 wet 9,7
5. cyl dry 8,5 wet 9,5
6. cyl dry 9,2 wet 10

Cylinder 3 is the worst, but none are good. Does anyone have any experience with something like seafoam? Don't think the car is valuable enough to replace piston rings.

Also, not sure if this is relevant or not, but I checked fuel trims today while idling and engine at operating temperature. Bank 1 long term was at 7% and bank 2 long term was at -4,7%. Is this an issue? Could the two issues be related?

[Linas.P]

All modern cars have issue with low compression rings... If your car is well above 100k miles then I don't think your results are unusual. 4GR-FSE as well has DI related carbon build-up on valves and that could as well contribute. Most of these issues are caused by extended service intervals, for IS250 I would say 6,000 miles is maximum between oil changes and even 3,000 would not hurt, especially if car is driven in the city or short journeys.

So question here would be - how many miles car has and how frequently it was serviced? Second question - how the walls of cylinders looks like? So if car is relatively low miles and cylinder walls don't have scratches then you can perhaps can get away with more frequent service, oil flush and some sort of carbon removal process and see if it helps. But if car is high miles, has damage to cylinder walls then there is no solution - new engine or simply drive it until it dies. 

Low compression and poor fuel economy, or imbalance between trims on banks could be related - yes... 

[perseuss69]

2 hours ago, Linas.P said:

All modern cars have issue with low compression rings... If your car is well above 100k miles then I don't think your results are unusual. 4GR-FSE as well has DI related carbon build-up on valves and that could as well contribute. Most of these issues are caused by extended service intervals, for IS250 I would say 6,000 miles is maximum between oil changes and even 3,000 would not hurt, especially if car is driven in the city or short journeys.

So question here would be - how many miles car has and how frequently it was serviced? Second question - how the walls of cylinders looks like? So if car is relatively low miles and cylinder walls don't have scratches then you can perhaps can get away with more frequent service, oil flush and some sort of carbon removal process and see if it helps. But if car is high miles, has damage to cylinder walls then there is no solution - new engine or simply drive it until it dies. 

Low compression and poor fuel economy, or imbalance between trims on banks could be related - yes... 

Fair enough. Car has 168k km right now. I've had it since 162k. Should have been a bigger red flag when at one point in the service history, there was a comment about the oil dipstick being completely dry.

Might have to take a look with a borescope at some point.

[Redefined]

If you have a situation where the history mentioned the oil being bone dry (well, as far as the dipstick could get/translate) then I'd have thought (if the issue is ongoing) then there will currently be water mixed in with the oil. Can you take a look and see if you can check/see.

How is your coolant levels? If the pistons/rings were still quite bad then maybe you'll see air in you coolant levels or dropping of coolant levels. I had bubbles in mine. According to Car Care Nut recent video about myths of car maintenance. He mentions the use of 'plugs'..

Stuff like K Seal or WonderWeld (there plenty others on the market now) which essentially plug any holes (if there is any). If you get to the point that a garage suggests this - and hopefully you won't - then don't take it. I also bought myself a boroscope as I had bubbles in the coolant and was losing it at the head gasket I assumed.

I used all sorts of 'plugs' like K Seal and the likes. I'd used K Seal successfully previously you see, but this time the leak was too great. I ended up clogging lots of stuff, including probably the radiator core. Was gonna have the engine replaced but thankfully the Subaru engine-replacement specialist spoke to his mates at Subaru MDs. They advised him not to do it.

I also spoke to another Indy who was ex Subaru and had done 6 of my car (3L horizontally opposed 6 cylinders) whilst working at Subaru. Again, he advised me not to on my engine as it only goes from bad to worse. Hopefully your situation isn't as bad but from the sounds of it (compression testing, investing in boroscope), you sound just like I was just last year this time!!

All the best, and remember keep smiling!! It really could be alot worse... 1st world problems n all that. For me the blessing came in the guise that I finally took the plunge to Lexus with the LS430 and here I am...

[Redefined]

NB. You mention about car having 162k and by 168k you're seeing the issues. Also sounds like what I went through as the car was just too good to be true. But there was something about the coolant that I just couldn't put my finger on. Had black bits show up every so often.

Could have been a coincidence but I really think the last owner (lovely couple who had all their work done at Sub Main Dealers) had been forewarned of the upcoming failure. Not too worry, it wss a lovely car for me and the 5 or 10 k it lasted me (from maybe 140k to 148k) was a whole heap of fund and comfort 😄

[Linas.P]

57 minutes ago, Redefined said:

 then there will currently be water mixed in with the oil. Can you take a look and see if you can check/see.

Not necessarily... if the car had stuck oil control rings and had excessive blow by and burning oil, then it can quite easily burn trough quite a lot of oil. 1L per 1000km is not unusual, in fact they get much much worse. 

Oil mixed with coolant/water is quite specific failure mode - that would be head gasket failure and 4GR-FSE are not known for head gaskets. The only way this happens on this engine is if water pump is not replaced in time and coolant leaks out (quite be quite rapid as well), then engine overheats and it could throw the gasket, but this is not common.

The oil control rings issue is more common, so I would not expect issues with HG, nor coolant, I would rather expect excessive oil burn, hence why it was low. As result of oil being low I would honestly be most concerned about crank bearings and how they look, I would look for "forbidden glitter" in oil pan. That would be my main worry, not head gasket.

How is you oil burn is looking? do you need to top-up often? 

[perseuss69]

7 hours ago, Redefined said:

If you have a situation where the history mentioned the oil being bone dry (well, as far as the dipstick could get/translate) then I'd have thought (if the issue is ongoing) then there will currently be water mixed in with the oil. Can you take a look and see if you can check/see.

How is your coolant levels? If the pistons/rings were still quite bad then maybe you'll see air in you coolant levels or dropping of coolant levels. I had bubbles in mine. According to Car Care Nut recent video about myths of car maintenance. He mentions the use of 'plugs'..

Stuff like K Seal or WonderWeld (there plenty others on the market now) which essentially plug any holes (if there is any). If you get to the point that a garage suggests this - and hopefully you won't - then don't take it. I also bought myself a boroscope as I had bubbles in the coolant and was losing it at the head gasket I assumed.

I used all sorts of 'plugs' like K Seal and the likes. I'd used K Seal successfully previously you see, but this time the leak was too great. I ended up clogging lots of stuff, including probably the radiator core. Was gonna have the engine replaced but thankfully the Subaru engine-replacement specialist spoke to his mates at Subaru MDs. They advised him not to do it.

I also spoke to another Indy who was ex Subaru and had done 6 of my car (3L horizontally opposed 6 cylinders) whilst working at Subaru. Again, he advised me not to on my engine as it only goes from bad to worse. Hopefully your situation isn't as bad but from the sounds of it (compression testing, investing in boroscope), you sound just like I was just last year this time!!

All the best, and remember keep smiling!! It really could be alot worse... 1st world problems n all that. For me the blessing came in the guise that I finally took the plunge to Lexus with the LS430 and here I am...

 

6 hours ago, Linas.P said:

Not necessarily... if the car had stuck oil control rings and had excessive blow by and burning oil, then it can quite easily burn trough quite a lot of oil. 1L per 1000km is not unusual, in fact they get much much worse. 

Oil mixed with coolant/water is quite specific failure mode - that would be head gasket failure and 4GR-FSE are not known for head gaskets. The only way this happens on this engine is if water pump is not replaced in time and coolant leaks out (quite be quite rapid as well), then engine overheats and it could throw the gasket, but this is not common.

The oil control rings issue is more common, so I would not expect issues with HG, nor coolant, I would rather expect excessive oil burn, hence why it was low. As result of oil being low I would honestly be most concerned about crank bearings and how they look, I would look for "forbidden glitter" in oil pan. That would be my main worry, not head gasket.

How is you oil burn is looking? do you need to top-up often? 

Coolant level is fine and has not moved whatsoever. Changed engine oil yesterday and it looked fine. Didn't see any glitter or water. The dry dipstick comment was made at 107k.

It burns about a liter of oil per 3000km or so I think.

[Linas.P]

4 hours ago, perseuss69 said:

It burns about a liter of oil per 3000km or so I think.

That would suggest either stuck oil control rings, or cylinder wall wear, because that is excessive. Basically, you would burn all the oil between the services and hence that explains why dipstick was dry... Obvious it has happened 60k ago, so it is kind of worrying when thinking about what is condition of engine now. 

1L/3000km is "within Lexus spec.", but that is because their spec is ridiculously "generous" for these engines. I think official allowed is 1 quart per 1000 miles or maybe 600 miles, something ridiculous like that. Anything better than that and they refuse warranty claim for "oil burning", but obviously this isn't healthy.

My old IS250 was burning 2L between services when it was ~130-150k miles (209-241k kilometres), as well it had common VVTi rattle on cold start. However, what I noticed was that all burn started after 5000-6000 miles and cold morning VVTi rattle would start around 6000 miles as well. So first I tried engine flush, made no difference to oil burn, but it would not rattle until 7000, maybe 8000 miles, and the oil was noticeable cleaner. Whereas without flush the oil would already be dark after 3000 miles, with flush even at 6000 or 7000 miles it would still be relatively clean.

So what I started doing was simply changing oil twice a year with flush every other time. So basically get service at Lexus once a year and in the middle of it did one oil change and flush myself... as I was doing ~12,000 miles a year, this worked out nicely to oil change every 6,000 miles. Since I started doing that I have never topped-up oil again and never had rattle from VVTi... all the way to 200k miles (and probably more if car wouldn't have been stolen).

Stuck control rings could get unstuck with some luck, will probably need few flushes and some sort of carbon removal service (I tried hydrogen, but can't say it worked...), but if there is already wear on the cylinder walls than nothing can be done.

[perseuss69]

2 hours ago, Linas.P said:

That would suggest either stuck oil control rings, or cylinder wall wear, because that is excessive. Basically, you would burn all the oil between the services and hence that explains why dipstick was dry... Obvious it has happened 60k ago, so it is kind of worrying when thinking about what is condition of engine now. 

1L/3000km is "within Lexus spec.", but that is because their spec is ridiculously "generous" for these engines. I think official allowed is 1 quart per 1000 miles or maybe 600 miles, something ridiculous like that. Anything better than that and they refuse warranty claim for "oil burning", but obviously this isn't healthy.

My old IS250 was burning 2L between services when it was ~130-150k miles (209-241k kilometres), as well it had common VVTi rattle on cold start. However, what I noticed was that all burn started after 5000-6000 miles and cold morning VVTi rattle would start around 6000 miles as well. So first I tried engine flush, made no difference to oil burn, but it would not rattle until 7000, maybe 8000 miles, and the oil was noticeable cleaner. Whereas without flush the oil would already be dark after 3000 miles, with flush even at 6000 or 7000 miles it would still be relatively clean.

So what I started doing was simply changing oil twice a year with flush every other time. So basically get service at Lexus once a year and in the middle of it did one oil change and flush myself... as I was doing ~12,000 miles a year, this worked out nicely to oil change every 6,000 miles. Since I started doing that I have never topped-up oil again and never had rattle from VVTi... all the way to 200k miles (and probably more if car wouldn't have been stolen).

Stuck control rings could get unstuck with some luck, will probably need few flushes and some sort of carbon removal service (I tried hydrogen, but can't say it worked...), but if there is already wear on the cylinder walls than nothing can be done.

Which brand and which products did you use for the flush?

[Linas.P]

I would not say it is the best product, but as far as I am concerned it worked, one of the cheaper products on market. So it is not like I particularly recommend it, but I was personally satisfied with how it works:

https://www.wynns.uk.com/product/engine-flush/

[Mr Vlad]

Blimey. It's like bolting the door after the horse has gone.

Bluntly speaking. You bought a high mileage car which had a problem or two in its life. You've put a lot more miles on it and are now having issues. 

Unfortunately your car has had uncaring owners in its past. You seem to be a caring one which is good. 

Yes try a product like Seafoam or that other one (I forget its name). Its best to use it through the throttle inlet. Do an oil change a day or two after. 

What brand of fuel do you use? Use Super Unleaded. Maybe have your car Terraclean. 

When you've done those things just make sure you do oil changes every 3-4k miles religiously. 

[perseuss69]

9 minutes ago, Mr Vlad said:

Blimey. It's like bolting the door after the horse has gone.

Bluntly speaking. You bought a high mileage car which had a problem or two in its life. You've put a lot more miles on it and are now having issues. 

Unfortunately your car has had uncaring owners in its past. You seem to be a caring one which is good. 

Yes try a product like Seafoam or that other one (I forget its name). Its best to use it through the throttle inlet. Do an oil change a day or two after. 

What brand of fuel do you use? Use Super Unleaded. Maybe have your car Terraclean. 

When you've done those things just make sure you do oil changes every 3-4k miles religiously. 

It's a 2008 that I bought at 162k kilometers. That is not high mileage.

The page I linked above says to make sure that the engine rpm should be above 250 to conduct the compression test. I'm fairly certain mine did not rev that high. So that might explain the lower compression readings overall, but it is still clear that one cylinder is way lower than the rest. Might try doing an engine flush with my next oil change. Perhaps I'll try getting a borescope to take a look at the cylinder walls.

I use 98-octane fuel from a decent brand.

At first glance it seems that Terraclean is a UK-based service? I'm from Eastern Europe.

[Linas.P]

25 minutes ago, perseuss69 said:

At first glance it seems that Terraclean is a UK-based service?

Yes Terraclean is hydrogen cleaning I had in UK, not sure if there are similar services anywhere else in Europe. 

[perseuss69]

2 hours ago, Linas.P said:

Yes Terraclean is hydrogen cleaning I had in UK, not sure if there are similar services anywhere else in Europe. 

Why'd you have the cleaning done?

[Linas.P]

1 hour ago, perseuss69 said:

Why'd you have the cleaning done?

Fuel consumption was getting suspicious and it thought it could be carbon related, but now I think it was rather related with lazy lambda/o2 sensor. In principle it was waste of money, has not changed anything about how car drove or sounded. Emissions were as always, fuel consumption as well. 

[Mr Vlad]

Ah ok J. I didn't know you was in Eastern Europe. But you still could try a product like Seafoam and do regular oil changes. 

Yes your car is high mileage and probably been mistreated in its life. I suggest if you can get it then get a bottle of ZX1 and put it in you fresh oil. It won't cure anything except noise tappets but it'll micro coat all metal in the engine where oil gets and put a protective coat on it. It'll preserve what you have now and really help in its future health. 

[perseuss69]

16 hours ago, Mr Vlad said:

Ah ok J. I didn't know you was in Eastern Europe. But you still could try a product like Seafoam and do regular oil changes. 

Yes your car is high mileage and probably been mistreated in its life. I suggest if you can get it then get a bottle of ZX1 and put it in you fresh oil. It won't cure anything except noise tappets but it'll micro coat all metal in the engine where oil gets and put a protective coat on it. It'll preserve what you have now and really help in its future health. 

I was looking for Seafoam, but it seems that you can only order it from the US, which is very expensive. The shipping alone was about $50 USD. I didn't find any European vendors for it.

[Mr Vlad]

Have you tried eBay for CRC Valve Cleaner or can you try eBay? 

Where in Eastern Europe are you?

[perseuss69]

3 hours ago, Mr Vlad said:

Have you tried ebay for CRC Valve Cleaner or can you try ebay? 

Where in Eastern Europe are you?

I think I tried looking for it, but did not want to order it from the US and didn't find it in the EU. I cleaned my valves using K2 carb/intake cleaner. Seems like the way to go would be to let the pistons soak with Seafoam, but in that case I'd only do it with Seafoam, not some other brands. Other than that I'd use Liqui Moly's engine flush with my next oil change.

I'm in Estonia.

[Mr Vlad]

Do you have any relatives or friends in the UK who could get a product and post to you?

[perseuss69]

12 hours ago, Mr Vlad said:

Do you have any relatives or friends in the UK who could get a product and post to you?

Actually, I might. Is Seafoam available in the UK?

[Mr Vlad]

Yes seafoam is available in the UK via eBay and even amazon. 

[perseuss69]

1 hour ago, Mr Vlad said:

Yes seafoam is available in the UK via Ebay and even Amazon. 

Could you post an amazon link for it? I can't find any Seafoam products on amazon.co.uk.

[Mr Vlad]

Sea Foam SS14 Engine Cleaner and Lube Foam https://amzn.eu/d/im9lNMx

Try this.

[perseuss69]

@Mr Vlad @Linas.P What do you think, should I only soak cylinder 3 (lowest compression) with Sea foam or all of them?