A few weeks back i asked you guys about an oil leak issue i was having. the valve cover didn't fix the leak so i took it back to the shop that did the engine swap a few weeks ago. i talked to him yesterday and the guy, who knows miatas and builds and races lots of them, told me the following.

He said the car was ready to pick up and he wants me to put some time on the car on track. I am hitting ECR in the DFW area Saturday. they replaced the cam angle sensor o-ring and the actual crank position sensor. he said the car was pushing oil out through the crank sensor and the seal was intact. He also said that under boost some oil was still leaking out of the car near the transmission bell housing but they can't find where it is coming from.

According to him they pulled the trans and the front cover to inspect all seals and they were all fine. he thinks the crankcase is building up pressure under boost and forcing oil past the seals, but not damaging them. The engine ventilation system is installed and working correctly according to Shannon. does that sound plausible? i am having issues with boost surge at high rpm and the car is set up to use the computer's boost control solenoid. could pressure somehow building up having to do with the surge that the engine cant vent through the factory crankcase ventilation system? The boost gauge shows 12 psi with an occasional surge to 15 and isn't reading constant boost.

for clarity, the car has a FMII turbo system with the base turbo (3650r?) running 12 psi and uses a Hydra 2.7 ecu.

 

It's probably a 2560. There's a big catch can / PCV thread on here that has lots of info in regards to positive crankcase pressure issues. I'd find the link but I'm about to go to bed.

 

What type of catch can do you have?

 

The car has a catch can, since i purchased it built i have no idea what brand it is. It has a large breather filter on top though. i don't have pics of the engine bay though and the car is at the shop not here at home.

Hustler suggests that i need a MSM PCV for the car. I'm wondering if perhaps the stock 1994 factory PCV on the car might some how be blocked allowing pressure to build. It is the one the car came with AFAIK.

Being a turbo noob this may be a stupid question. could pressure not venting through a PCV correctly have anything to do with boost surge? the boost gauge does show normal boost range though.

 

You want this PCV
http://www.flyinmiata.com/index.php?...umber=04-96005

IIRC it's from a 323gtx

You're pressurizing the crank case with the stock PCV

 

Thanks for the link. I'm tracking saturday and hopefully I can find the MSM part locally.

 

Why would you buy the inferior MSM pcv? Get one for the 323 gtx.

 

MSM PCV is the same as the standard one IIRC and it leaks too.

323GTX or get a new rubber valve cover PCV gasket with a smaller hole and use an OEM all metal one from a turbo Supra.

Another option is something simple, like a check valve...