Spec_Ops2087

Hey Everyone,

So this problem is really getting the best of me. Once my oil / coolant temps are up to operating temp, at an idle, if I give it a slight rev i'll get a nice cloud of smoke out the back. To be clear, at idle (low oil pressure) it will not smoke but if I give it some gas, as the rpms bump up a cloud of smoke also comes out. The car does not smoke while driving, accelerating, engine braking, etc. Only at a warm idle when blipping the throttle.

Car has an IP log manifold setup (bottom mount turbo) with a GT35 BB turbo - IP originally installed the kit way back when with the oil drain tapped into the front of the engine in the oil pan, basically directly below the crank pulley. The drain hose was a 90 degree fitting directly off the turbo and a slight downward slope to another 90 and then into the pan. I had no smoking problems for years. Turbo has always had a .035 restrictor with a -4AN feed and a -10AN drain, pretty standard for the s2000.

A while back I noticed some sweet smells coming from the exhaust and after about 40k miles my 3mm HG needed to be replaced. Billman did that, car was retuned everything was well again.

As I've been getting older, the whole obnoxious exhaust thing wasn't quite my style anymore so I had a custom exhaust built that had a real muffler on it and a recirculated dump tube. I'm not sure if by chance or what but around that time, I started to notice puffs of smoke at idle (see above for exact conditions). As a first easy measure, I redid the drain line - instead of a 90 fitting off the turbo, I put a 45 degree fitting off the turbo which then slopes down and into a 90 that goes into the block. It def drains better than before but it didn't change the smoking situation any. Given the turbo had about 60k miles on it at this point but over 10 years of service I figured it might be time for a CHRA replacement. I sent the turbo out to ATP turbo and had the CHRA replaced. I reinstalled and I'd say the smoking was 80% better. Then after a few weeks it's pretty much back to the same issue.

Thinking it's not the turbo, I did a compression test ~210 across the board, and also a leakdown test 7 / 9 / 5 / 4 - all good. I just got finished replacing the valve seals (just in case, car has about 80k miles but is a 2002) and that hasn't helped either.

So here I am, at a loss of what the issue could be...I have a .030 restrictor on order to try and I'm also going to run to HD at some point and pick up some clear hose to temporary put on the drain line to visually see what the oil is doing. I've been scowering the internet and almost everything comes back to drain or PCV system. I have the supra PCV inline with the stock one (confirmed working with pressurized air) and my front breather just has a mini filter on it. Based on what I've read, it might be worth while either installing a check valve on the front breather to put vacuum on the crank or route it behind the turbo intake (before compressor obviously) to again help get some vacuum into the crank.

Only other things I can think of is that my new CHRA is bad? What are the odds... Also, would increasing the backpressure in the exhaust someone cause smoking in the turbo? Like I said, strangely this all started happening around when I got the new exhaust...

Any thoughts??

JUSTINTHECOASTIE

Maybe time for a turbo rebuild, leaking lines or seals. How old is the turbo? Mileage?

Spec_Ops2087

New CHRA installed less than 6 months ago. Didn't seem to help either.

Charper732

Pull the IC pipe off the turbo and see if there is oil residue in it.

JUSTINTHECOASTIE

is your turbo water cooled? Possible leak in the water passage seal? Have you used another restrictor? The sweet smell is what I'm worried about, unless you're on race gas/e85

Mijae007

I bet you either have too much oil in it, or your drain location needs to be higher. With your car on level ground, undo the an fitting on the pan, if oil pours out you have your answer.

Spec_Ops2087

I should have specified, the smoke is def oil. Blueish in color, smells like burning oil. When I pull the car into the garage, the whole place smells like an oil fire.

I have a .030 restrictor on the way, down from .035 that I have now. Going to see if that helps out.

Spec_Ops2087

I took off the drain line and nothing comes out so pretty sure it's above the oil line, now by how much I don't know. It's tapped basically below the crank pulley which I've read is the best spot for the pan.

I made a clear oil drain hose to see if it is actually backing up. Tomorrow I'm going to let the car heat up and see what it does. I tried it real fast just to see if it leaked and it was totally filled with oil while running but I'm assuming that's because the oil was like molasses (sub 60F). Within a couple of seconds of shutting the car down the line was completely clear.


As I said earlier, the car never smoked with this same setup and then it started to smoke, very strange...

Spec_Ops2087

So i just checked, the intercooler line is 100% dry. I also unbolted the catback bolts to take a look inside the exhaust pipe and it had condensation in it but nothing oily.

JUSTINTHECOASTIE

lol no worries. I think you are on the right track then. Turbos and oil getting by is nature of the beast. Are there any oil spots at or around the turbine hot side?