Oil fill cap blow

[doikov_87]

Anyone has any thoughts on that?

 

Hi

[TonyHSD]

Hi, this can be as a result of excessive blow by due to a worn out piston rings and cylinders or an issue with pcv valve, and hoses. Best to check pcv valve first and then compression test. Any other problems like oil consumption, difficult start when cold ? 

[doikov_87]

Could it be an injector blowing high pressure diesel if the copper washer is leaking?

[furtula]

Any issues other than that? Car pulls fine, consumption went up, or still same? Mileage of the car?

 

[doikov_87]

Car is 146k miles. Fuel consumption went up a bit. Doesn’t pull as it was. Smoke coming from exhaust. Sometimes hard to start in the morning. 
I did a little experiment today. Started the engine and opened the oil fill cap halfway. Then unplugged the control cables on each injector one by one. When I unplugged injector 2 that hissing chuffing sound significantly reduced. Does that prove that the problem is piston rings or leaking injector. I’m confused…

[doikov_87]

Also the level of the oil is down. At the minimum at the moment. Could it be because of oil thinning due to fuel leak from injector leading to oil to be burned or it just burns oil because of worn piston rings?

[TonyHSD]

1 minute ago, doikov_87 said:

Car is 146k miles. Fuel consumption went up a bit. Doesn’t pull as it was. Smoke coming from exhaust. Sometimes hard to start in the morning. 
I did a little experiment today. Started the engine and opened the oil fill cap halfway. Then unplugged the control cables on each injector one by one. When I unplugged injector 2 that hissing chuffing sound significantly reduced. Does that prove that the problem is piston rings or leaking injector. I’m confused…

I am not sure 100% either is from injector or piston rings.  Perhaps a garage with equipment and compression test, or look inside the cylinders with camera may point you to the right direction. If you unplug the injector 2 you cut the supply of fuel and eventually reducing the blow by, the discovery you made is more like on which cylinder  is the issue. Usually whatever comes out from top of the engine oil cap actually is coming from the crank case, the only way to get gases entering there is via cylinders imo. 

[doikov_87]

9 minutes ago, TonyHSD said:

I am not sure 100% either is from injector or piston rings.  Perhaps a garage with equipment and compression test, or look inside the cylinders with camera may point you to the right direction. If you unplug the injector 2 you cut the supply of fuel and eventually reducing the blow by, the discovery you made is more like on which cylinder  is the issue. Usually whatever comes out from top of the engine oil cap actually is coming from the crank case, the only way to get gases entering there is via cylinders imo. 

Another thing… I have a Launch Creader v+
i have a reading of 32100kPa on fuel rail at idle. Is that normal pressure? If the injector is leaking would I be able to find out by that?

[furtula]

Looks to me like it's burning oil, so might be issue with cylinder/piston rings. 

I think best would be to do a compression test as said above, and go from there.

If they don't find anything, they can check injectors.

 

[TonyHSD]

2 hours ago, doikov_87 said:

Another thing… I have a Launch Creader v+
i have a reading of 32100kPa on fuel rail at idle. Is that normal pressure? If the injector is leaking would I be able to find out by that?

Sorry , I can’t answer that,  it will need to be checked by professional and all measures compared to manufacturers defaults. 
Good luck 👍

[Bernard Foy]

Compression test would be my starting point.

[doikov_87]

6 minutes ago, Bernard Foy said:

Compression test would be my starting point.

hi

If they do a compression test wouldn't that just confirm that there is a problem with that cylinder, but not show where it loses compression. could be from the piston ring, but also could lose compresion due to injector not sealed properly?

[doikov_87]

Obviously the car is losing oil. I was wondering if it will lose oil due to oil thinning the same way as if the piston rings were not sealing properly.

[Bernard Foy]

Well when there is several possible causes to a problem, I start with the most probable cause and a compression test will either rule in or out if one or more of your cylinders are not up to the manufacturers tolerances.

[furtula]

Gunked up pistons is not an issue on 1.6 engines, so they should be sealing just fine.

The car is not loosing oil, but probably burning it, not really the same.

Either way, it's not worth fixing the pistons issue. 

I'd either see if it's an injector as you said, if not, maybe better to put another engine, or get rid of the car.

[doikov_87]

Update.

Injectors replaced with new ones, problem disapeared.