Hey guys had this 1991 tt of mine running for 3months, last month I noticed one side of exhaust is flowing smooth, other side/left is sort of rough, i started the car this morning let it idle till operating temp, gave it some lil rev, its burning oil consistently on left exhaust side, Im sure its oil because it bluish and smells like burnt oil. I was thinking that maybe the piston rings on the other bay maybe worn, turbo seal, or otherwise something else. From what I heard from the previous owner is it had a rebuild about 3-4 years ago, when he bought it it hardly gets driven, he only mange to put 200 kilometres on it after 2 years of ownership. Checked my radiator coolant no sign of oil mixing with it, took the radiator cap and gave it a rev the coolant hardly rises which gave me an idea that Head gasket is going strong. Im aware that there is also leak around the right rocker cover gasket. So what do you guys reckon? Im keen to pull the motor, but i may hae to perform some compression test first. Thanks guys
Best case scenario would be the rocker cover gasket , you'll need it up high so you can visually see if it's leaking . Worst case is a blown Turbo , engine out and replace or rebuild BOTH .
Valve stem seals, oil rings, turbo seals, PCV's.... all can cause smoking exhaust. Some have even found that an exhaust without a centre H or X pipe can result in the same. PCV's are the easiest, and most commonly overlooked- they get gunked up. Pull them from plenum, soak in petrol until they are free moving. Will have a soft spring that returns them to the closed position. Without proper receipts, wouldn't take anybody's word on engine work. Pics of the car? Feel for the day a new member signs up, sporting my old Z
Yeah I may have to pull the plenum off, to tet them pcv's out, I pulled both intake hoses to check for oil residue for potential blown turbo seal or maybe just leaking its quite dry, I don't have x or h type exhaust, separate system for each bay, still wondering why my other exhaust flows better and smooth while other one isn't, doesnt seem to be missfiring. Although on cold start i do have missfires till operatig temp is reached
You were right the first time......compression test it. If the compression is within specification then diagnose the issue. When you pull the spark plugs, it should be obvious which cylinder/s require attention.
Compression test will show you if you have a big problem, if turbo seal was/is leaking it would not affect the operation of engine at idle.
You don't have to pull the plenum to get the p.c.v's out. You also need a X or H pipe to balance the exhaust flow or it can blow smoke for some strange reason. It's called the vibe I think
