2015 Buick Regal 2.0, piston or valve failure

vancexszafranz

New member
Joined
Sep 13, 2022
Messages
4
Reaction score
0
Points
1
Buick Ownership
Regal
Good morning everyone this is my first post! I am currently in the middle of diagnosing my 2015 Buick Regal with the 2.0 Turbo LTG motor. it has about 104,000 miles.

To begin with, the vehicle was driving fine, and threw a solid check engine light. I immediately had it ran and it was a cylinder one misfire. Naturally I got a set of plugs, and replaced them. This seemed to solve the issue, the car ran and drove for another day or so.

I then checked the oil level which was lower but not low, and topped it off. I drove about 100 miles round trip the next day, in which everything went fine until I literally was turning down my street going home and I got a flashing check engine light with the traction light on and the car was shaking some.

I parked it and went to bed. The next morning I decided to replace the coils, and that did not seem to help. I then pulled the plugs and noticed cylinder number one was wet with what looked like oil. The car was not running good at all. I opened the oil fill cap and started the car in which is seemed to have excessive blow by.

I then checked the oil level and noticed it was down to the bottom of the cross hatching mark already after I topped it off the day before.

Currently have done a compression test which led to cylinder #1 20/15 psi cylinder #2 140 cylinder #3 115 cylinder #4 140

Then I did a leak down test and cylinder #1 failed it

I bought a bore scope and went into all four cylinders. Cylinder #1 did not appear to be obviously cracked or broken on top although a fair amount of carbon buildup was found.

I also drained the oil and am going through it in which there is no obvious flake/ debris but it did not look unusual.

At this point I am trying to figure out if it is piston and or ring related or stuck/ bent valve related.

Any input would be greatly appreciated! thank you.
 
If you pressurize the cylinder and remove the oil fill cap and assume a piston/ring failure, I would assume a noticeable difference in blowby compared to other cylinders. If no difference than would think valve related.
 
If you pressurize the cylinder and remove the oil fill cap and assume a piston/ring failure, I would assume a noticeable difference in blowby compared to other cylinders. If no difference than would think valve related.
The issue definitely seems to be isolated to Cylinder #1, if its valve or piston related it will be the same plan of attack getting the head off. The compression and leak down both point to rings.
 
Good afternoon. 99% of the time, the piston has left the chat! We need to disassemble it and inspect it. At best, the piston needs replacing; at worst, the block is scratched and needs to be either relined or reground during the first overhaul.

Добрый день. 99% поршень покинул чат! Надо разбирать и смотреть, в лучшем случае поршень под замену, в худшем блок поцарапан и его надо либо гильзовать, либо точить при первом ремонте.

In Ukraine, this is a common problem due to poor quality fuel!

В Украине из-за некачественного топлива это распространенная проблема!
 
______________________________

Help support this site so it can continue supporting you!
Just having my first cup of coffee so beware of my advice. As mentioned above. Rotate the engine until that cylinders valves are closed. Pressurize it. If it has blowby to the crankcase it is likely rings/piston. If it blows out the exhaust it is likely valves. There are always exceptions. As it is not going anywhere you have a few choices. I don't know that engine at all, but how hard would it be to pop the valve cover/head off? 15/20 pounds of compression shows it is not likely to be a pain-free quick fix. Be prepared for a rebuild, salvage engine, or crate engine swap. You could get lucky and only require head work.
 
Im having same exact issue same exact vehicle. What did you find out about yours?
 
Back
Top