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Discussion Starter · #21 ·
Here is a video of my startup after work, was sitting outside for about 9 hours. Outside temp was 86 F. With 65% humidity. When driving and sitting at a light on idle, I did notice that my AFR gauge would sometimes (like 2 times my 15 mi commute home) jump to 15.7 back to 14.1 for a moment.
 

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Its hard to tell by those pictures but are those the face of the valves that are wet? If so, then I would suspect some valve seal leakage. If they are bad enough, I would think it would lead to some unfavorable leakdown results. It would also contribute to your oil consumption.

Have you noticed any smoking while driving/accelerating or smoking on start ups? What about smoking from the exhaust after you have let the engine idle for let say 20 mins and then revving it?
 

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Here is a video of my startup after work, was sitting outside for about 9 hours. Outside temp was 86 F. With 65% humidity. When driving and sitting at a light on idle, I did notice that my AFR gauge would sometimes (like 2 times my 15 mi commute home) jump to 15.7 back to 14.1 for a moment.
Usually the enrichment map adds fuel to get the car up to temp faster, yours did that and slowly dropped down and the AFRs came up slowly as they should have ... a bit lower than I'd usually want and idle at temp, but a leak would generally cause a higher AFR not lower. You may have just ran too rich, washed out the rings, and they leak. When is the last time you changed your oil? I'd do a Blackstone or other oil analysis to see what the oil looks like. It sounds pretty ok otherwise ...

A blown ringland (and compression loss) looks like this (my old video of me killing my stock engine):

If you have a valve issue, it make take longer to crank ovr and start and you might "puff" out smoke (usually blue) ... head gasket issues puff out white (coolant) smoke.
 

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Discussion Starter · #24 ·
Usually the enrichment map adds fuel to get the car up to temp faster, yours did that and slowly dropped down and the AFRs came up slowly as they should have ... a bit lower than I'd usually want and idle at temp, but a leak would generally cause a higher AFR not lower. You may have just ran too rich, washed out the rings, and they leak. When is the last time you changed your oil? I'd do a Blackstone or other oil analysis to see what the oil looks like. It sounds pretty ok otherwise ...

A blown ringland (and compression loss) looks like this (my old video of me killing my stock engine):

If you have a valve issue, it make take longer to crank ovr and start and you might "puff" out smoke (usually blue) ... head gasket issues puff out white (coolant) smoke.
I am going to have another shop look at it, and probably rebuild the heads if needed and get it re-tuned.
Also great video seeing an EJ putting in the work till it died on the track.
 

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Looking at the pictures closely, there is some piston damage and very worn cylinder walls.

In this picture you can see where it looks like the edge of the piston crown is missing. The red line follows the 'ledge' where material is missing.
Automotive lighting Gas Audio equipment Trunk Automotive exterior


Similar comment as above, missing material from the piston along the edge of the crown.
Automotive lighting Automotive tire Automotive light bulb Trunk Point-and-shoot camera


The bore area in the red box is suspect. The red line follows a very distinct difference in cylinder wear pattern. The bore below the line is almost polished where the cross-hatch can be seen above it.
Gadget Font Rectangle Material property Electronic device


Motor vehicle Automotive lighting Automotive tire Window World

Many different scenarios could have caused these issues so I'm not going to venture a guess; however, it appears you have a few problem areas at play here.
 

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Given the block is bored to 99.75mm, should I be looking to bore the block to 100mm get new pistons and build my heads? That is what it is sounding like.
No way to tell what's needed without measurement and inspection. IMHO, you are in for some engine parts on this short block.
 

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Looking at the pictures closely, there is some piston damage and very worn cylinder walls.

In this picture you can see where it looks like the edge of the piston crown is missing. The red line follows the 'ledge' where material is missing.
View attachment 67026

Similar comment as above, missing material from the piston along the edge of the crown.
View attachment 67027

The bore area in the red box is suspect. The red line follows a very distinct difference in cylinder wear pattern. The bore below the line is almost polished where the cross-hatch can be seen above it.
View attachment 67028

View attachment 67029
Many different scenarios could have caused these issues so I'm not going to venture a guess; however, it appears you have a few problem areas at play here.
Very interesting observations. I couldnt tell if it was piston material or not. I assumed it was just built up carbon/oil since there is wetness. I also did notice a strange marking on the piston dome. Cant tell if that just the scope or not. Scope pictures are hard to decificer most times
 

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It would be awesome to do a post-mortem on this engine. I would love to put my profilometer on the bores. I would also be interested in the piston ring free gap on the damaged pistons.
 

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With the cylinder pressurized during leak down, did you listen to the intake/exhaust/PCV to determine where you are leaking pressure? This will tell you if you have a piston ring or valve sealing issue... You can put your ear up to the intake and then exhaust and hear if the air is escaping into either.
 

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<snipped> I would also note that the people who did the actual tests yesterday notated crank case leaks on all 4 cylinders and on 2 and 3 intake/exhaust leaks.
By looking at the pictures, these observations, and reading between the lines, the shop performing the tests observed the following.
1. an audial or visual observation of pressure escaping the cylinders and into the bottom end during the leak down test. This would indicate a ring seal problem
2. an audial or visual observation of cylinder 2 and 3 intake and exhaust sides leaking during the leak down test. This would indicate a valve sealing problem.

This is just a guess based on the information provided.
 
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By looking at the pictures, these observations, and reading between the lines, the shop performing the tests observed the following.
1. an audial or visual observation of pressure escaping the cylinders and into the bottom end during the leak down test. This would indicate a ring seal problem
2. an audial or visual observation of cylinder 2 and 3 intake and exhaust sides leaking during the leak down test. This would indicate a valve sealing problem.

This is just a guess based on the information provided.
Ah I missed that comment at the end of the post. Thanks.

I just watched the video of cold start/idle, and it seems hard to believe you have the issues listed in the first post. With any significant valve leak, the car would likely have a fairly rough idle and would drive noticeably awful...

Personally, I'd get a second opinion. Or purchase a compression tester, some basic hand tools, and a small pancake/etc air compressor and test for myself. You don't need a percentage for identifying the problems you are hunting. You can remove the schrader valve from a standard compression tester end and hook the compressor up to pressurize the cylinder at TDC with the car in gear and ebrake on. Then, just listen around for leaks as I mentioned in my previous post. Anything that is broken will be obvious based on how much air is leaking into the intake, exhaust, or crankcase. And you'll probably have an idea of which one to test based on compression test results.

I broke ring lands a few times on the KA24 (all four once, and three another time IIRC) and it was very noticeable. Took like 10-15 seconds of turning over to slowly come to life, blew obvious blue smoke, and consumed oil like crazy. I also had a cracked valve at one point that did not show up on either test, but EGT was through the roof under load. Obviously something went on at some point in your engine as evidence of what @405HP_Z06 pointed out in the pics and I'd want to put eyes on it, but it may not necessarily affect how your car currently runs.
 

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Ah I missed that comment at the end of the post. Thanks.

I just watched the video of cold start/idle, and it seems hard to believe you have the issues listed in the first post. With any significant valve leak, the car would likely have a fairly rough idle and would drive noticeably awful...

Personally, I'd get a second opinion. Or purchase a compression tester, some basic hand tools, and a small pancake/etc air compressor and test for myself. You don't need a percentage for identifying the problems you are hunting. You can remove the schrader valve from a standard compression tester end and hook the compressor up to pressurize the cylinder at TDC with the car in gear and ebrake on. Then, just listen around for leaks as I mentioned in my previous post. Anything that is broken will be obvious based on how much air is leaking into the intake, exhaust, or crankcase. And you'll probably have an idea of which one to test based on compression test results.

I broke ring lands a few times on the KA24 (all four once, and three another time IIRC) and it was very noticeable. Took like 10-15 seconds of turning over to slowly come to life, blew obvious blue smoke, and consumed oil like crazy. I also had a cracked valve at one point that did not show up on either test, but EGT was through the roof under load. Obviously something went on at some point in your engine as evidence of what @405HP_Z06 pointed out in the pics and I'd want to put eyes on it, but it may not necessarily affect how your car currently runs.
This may be one of the situations where you found some problems before catastrophic failure. None of the cylinders are dead so the cylinder to cylinder reversion is probably hiding some of the symptoms. A second opinion is always good; however, it appears the first shop did a good job of diagnosing potential problem areas while providing visual reference.
 

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Discussion Starter · #36 ·
Ah I missed that comment at the end of the post. Thanks.

I just watched the video of cold start/idle, and it seems hard to believe you have the issues listed in the first post. With any significant valve leak, the car would likely have a fairly rough idle and would drive noticeably awful...

Personally, I'd get a second opinion. Or purchase a compression tester, some basic hand tools, and a small pancake/etc air compressor and test for myself. You don't need a percentage for identifying the problems you are hunting. You can remove the schrader valve from a standard compression tester end and hook the compressor up to pressurize the cylinder at TDC with the car in gear and ebrake on. Then, just listen around for leaks as I mentioned in my previous post. Anything that is broken will be obvious based on how much air is leaking into the intake, exhaust, or crankcase. And you'll probably have an idea of which one to test based on compression test results.

I broke ring lands a few times on the KA24 (all four once, and three another time IIRC) and it was very noticeable. Took like 10-15 seconds of turning over to slowly come to life, blew obvious blue smoke, and consumed oil like crazy. I also had a cracked valve at one point that did not show up on either test, but EGT was through the roof under load. Obviously something went on at some point in your engine as evidence of what @405HP_Z06 pointed out in the pics and I'd want to put eyes on it, but it may not necessarily affect how your car currently runs.
You all have been so helpful.
I’m going to take it to a shop that can rebuild heads and blocks to have them take a look into it. I don’t got money for a new long block. So hopefully a rebuild will suffice. I’m not entirely sure what they did during the test. But when I go to this other ship I will ask them.
 

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You all have been so helpful.
I’m going to take it to a shop that can rebuild heads and blocks to have them take a look into it. I don’t got money for a new long block. So hopefully a rebuild will suffice. I’m not entirely sure what they did during the test. But when I go to this other ship I will ask them.
I know it would suck to do this. But if a rebuild will not suffice, an oem type ra block will be cheaper than a built one. And if you don’t have another car could hold you over. Yes you’d need to retune and pull power out of it to be reliable. But it would be quite a bit cheaper. Just food for thought. I hope it is a simple fix for ya.
 

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Discussion Starter · #38 ·
Update for over the weekend.
I drove the car a collective 300 miles + over the long weekend, with no issues. Here are my findings. I was checking the oil every other day. And there was not a drop missing it all stayed consistent to when I changed the oil last week. There was zero knock outside of a few readings from shifting. I kept the boost under 5 psi the entire time. No change in coolant level and everything else is working as it should. I revved the car to about 3k to see if any smoke came out, there was none. On cold starts with 10w-40 smoke starts within about 1 min and goes away within a few. There is not color to it. As I can see the condensation forming and steaming off the top the exhaust pipes. I am planning to take this to another shop some time next week for a second opinion, but this is giving me hope. I know the photos are not pretty, so if that is true and the images reflect the state of engine. I was glad to take the right steps and asking knowledgeable individuals about the issue. I will have an update after the next leak down test.
 

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Discussion Starter · #39 ·
Alright this is what I got as a second opinion.
They did a hot test right after I dropped off the car.
Compression was worst with all cylinders sittings at 100-110 PSI. Leaks between 30-50%
They said they can hear the leak coming from the crankcase using an auto stethoscope. And that I really should not be driving the car at all.
They quoted me about $2,200 to pull the block inspect to see what is going on with it. Again, no oil was leaked or burned since the last oil change and I have been checking it frequently. I need to figure out what I am going to. They said just to pull the block it is going to be between 2-3 weeks. And that is not including the lead time it will take to source parts. I am not going to sell the car, I do not want to dick someone over and I defiantly do not want to sell it for a loss. I love the car, I want to get it fixed. I am deciding if I save money to do a full rebuild with a long block, new injectors, fuel lines, turbo and tune ect. Or do I just get it fixed to get it back to where it is. My goals with this car power wise are not out of reach at about 500 WHP. Thanks in advance.

Side Note: as another backup. I am awaiting results from blackstone on an oil sample to see what they have to say.
 

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If that's your plan, just drive it till it dies.

If the drivability is not impacted I see no reason to park it especially if you're going to do a long block anyway.

It doesn't make sense you have such bad leakdown but the car drives fine. When I lost compression on both my OEM and built motor it was definitely noticeable and the drive ability was poor.
 
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