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Discussion Starter #1
Good day to all!
I do not have a service book, so I’ll ask a question here.
Do I need to change chains and VVT sprockets on a 2.0T engine?
The vehicle's mileage is 225,000 km, it began to eat oil (valve stem seals needs to be replaced), the engine shakes and does not work smoothly. There are no errors.
 

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2017 SS Sedan 6.2L
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I don't know of any cases on the forum of timing chains issues on the 2.0T engine. Have you examined the spark plugs, throttle body, MAF sensor, and intake for any other possible maintenance issues?
 

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Discussion Starter #4
It is necessary to completely disassemble the engine to make sure the pistons are broken? Can this be determined by checking the compression?
If you carry out these works, is there any point in replacing the chains with mechanisms and valve stem seals?
 

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Discussion Starter #6
Tell me please, it is possible to receive correct oscillogram of synchronization between camshafts and crankshaft?
Where can I get this information for comparison with my car.
 

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Discussion Starter #7
I don't know of any cases on the forum of timing chains issues on the 2.0T engine. Have you examined the spark plugs, throttle body, MAF sensor, and intake for any other possible maintenance issues?
The throttle valve is clean and working, the candles are new, the MAF sensor is in order, the new air filter. More recently, I cleaned the intake valves from carbon.
 

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Discussion Starter #8
Tell me please, it is possible to receive correct oscillogram of synchronization between camshafts and crankshaft?
Where can I get this information for comparison with my car.
I again ask to help you find the waveform. Can someone tell me where I can get it or buy it?
 

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2011 Malibu LTZ 3.6L V6 Red Jewel Tintcoat
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I'm not sure I understand what it is that you need. An "oscillogram" is a picture of the waveform that is produced by an oscilloscope.

Do you mean that you need the instructions for installing the timing chain?
 

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Discussion Starter #10
I'm not sure I understand what it is that you need. An "oscillogram" is a picture of the waveform that is produced by an oscilloscope.

Do you mean that you need the instructions for installing the timing chain?
I am looking for an waveform (oscillogram) (taken by an oscilloscope on a well-functioning engine) between the camshafts and the crankshaft
I need an oscillogram to compare with my motor. Perhaps someone took such measurements or knows where it can be purchased.
 

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2016 Malibu 1LT 1.5T
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Sorry, I saw "compression" and added "ratio".

GM publishes just about every value there is for the engine, but not the actual pressures expected.

The general rule is that they should all be about equal, within about 10-20% from the highest to the lowest. I would tend toward 10% myself since it has only 4 cylinders instead of 8 to split that difference.
 

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Free information can only get a person so far. The information you're looking for people pay for it.

With that being said, compression should be around 140 PSI (9.65 bar) per cylinder and like DD said, all cylinders should be within 10% of each other.
 

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Discussion Starter #17
Made a measurement of compression. Results below
1 - 9 bar
2 - 9 bar
3 - 7 bar
4 - 9 bar.
I understand that need to remove the cover and look there? Or just need to think about the overhaul of the motor?
 

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Sounds like #3 may have a cracked piston or a valve issue. 2 BAR less is not good.
 

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Discussion Starter #19
Sounds like #3 may have a cracked piston or a valve issue. 2 BAR less is not good.
Need to open the engine and do troubleshooting?
Does the cylinder or valve change piece by piece or does it need to be changed all at once?
 

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I believe there are updated pistons for these engines. I'm am not 100% sure as I do not have one of these engines.
Others may have a more definite answer.
For what it takes to change one you would be wise to change all 4.
 
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