Do I need a rebuild?

[Novablue454]

I just got done doing a compression test on my 90 tsi. The results are not good. Im thinking it needs a rebuild, but I'd just like some opinions.

cylinder 4 = 90
cylinder 3 = 89
cylinder 2 = 90
cylinder 1 = 110

when I put some oil in cylinder 4 and tried it again, the compression was right at 160, spec according to my book.

Did my rings give up the ghost?

 

[flyinghighlm]

More than likely its the rings and combined with a bad HG...looks like you have some work ahead of you. Best of luck to ya.

 

[Eclipsethis90]

If you are relacing rings I would highly recommend replacing valve seals at least and if possible having a basic head rebuild at the same time as new rings.

 

[coryd]

Before you start spending money to rebuild it, do a leak down test find out where the leaking is from first. there is many other things that could cause this. The valves could be dirty/sticking open. When you do the leak down pull out the dip stick and if air is comin from there then start suspecting rings. If it comes out of the exhaust manifold, or intake it could be the valves. Open the rad cap, any bubbles from the coolant could be head gasket.

 

[Novablue454]

ok, i'll go pick up a leak down tester tomorrow. Any tips on how to get the cylinders to TDC? Ive only used one of these once before, and it was the biggest PITA ever.

 

[Novablue454]

Ok, I just got halfway done doing a leakdown test, and im terribly confused. Either im doing this wrong, or somethings happening that I dont realize.

I set Cylinder 1 to TDC using the long screwdriver method. I then screwed in the hose from my compression tester. I set my air compresser to first 60, then 105 psi. I then connected the compressor to the tube into the cylinder. The cylinder held pressure and there were no audible leaks. Is this the correct way of doing it without having the actual tool?

and another question on a side note. Shouldnt cyls 1 and 3 be at TDC at the same time? I tried this on both cylinders with the same result, however 3 seemed to be at BDC when 1 was at TDC.

 

[Novablue454]

nevermind, im an idiot.

the compression tester tube has a schrader valve in it so no air was coming out. Looks like I have to try to hunt down a real one tomorrow.

sometimes I just have laugh at my stupidity. Perhaps thats why no one else works on their cars at 1:15am.

 

[Novablue454]

Ok, I removed the schrader valve and tried again. On Cyl 1, air blows hard out of the dipstick. So its rings. Cly 2, Air leaks out intake. Valves. Cyl 3 same as two, except a bigger leak.

Does anyone know anywhere cheaper then slowboy for the stroker kit?