xsboredom1

Hey guys,

So i've been having this issue for a few months now and am still trying to confirm things before I put money down to have the head rebuilt or turbo rebuilt again. Here's a little background on the car: it's an imported f23a with unknown mileage but had amazing compression when i first bought it. Has arp headstuds and no notable overheating issues. Turbo setup is basic with a treadstone log, garrett t3/t4 50trim, etc etc. -3 feed, -10 drain.

Have had a smoking issue since i originally (conicidentally?) put this turbo on. The turbo was bought used and I already knew that there might have been bad seals as the compressor housing had some oil residue. The car would smoke on cold start idle (after a min or two) if i let it sit. Once driving, no smoke while driving after the initial smoke dissipates. There is no smoke on decel or boost (that i can see) but if I let the car sit at idle for extended periods (traffic) it will slowly start having little whiffs of smoke appear. It also smokes at idle with hot starts if the car sits for 15 minutes or so. leaking valve seals confirmed?

I pulled the turbo and had it rebuilt back in June by Comp Turbo and put it back in the car. They originally advised me that my -3 and -10 setup was fine so i kept it. Although i thought it was fixed, after a day or two i noticed the smoke again. Next was addressing an iffy return line so I redid it and got rid of a lot of the angle and the possible kink and even picked up one of those new fangled PRL ported return flanges. No change. Next was trying out a restrictor so i threw on a 0.065 restrictor atp turbo and it seemed to have helped a little but it still smokes.

Part of me doubts its the turbo since it does not smoke on boost or after hard driving but it's a possibility. I should probably pull the downpipe and check if there's oil but it's a pain the butt so right now i'm just going through some theories.

Valve seals? Return line still not draining properly? Feed line? Any tests i can do to check this? Leak down i'm assuming?

Aradin

It sounds like you have the drain sorted so I wouldn't really suspect it unless you have the bung up super high on the pan and the girdle/windage tray is in the way. I have seen this issue before on H/F series but typically that will cause smoke all the time and oil oozing past the turbo seals. Getting the fitting in the proper spot can be tricky on the F23s because the girdle is bolted to the block for rigidity and is pretty cumbersome. You can check this by using a screwdriver or something of that sort and poking into the drain fitting on the pan to see if you have ample clearance behind it. As long as you have about an inch it should be fine assuming the line isn't kinked, doesn't have any intense angles and the lowest point of the drain is where it connects to the pan itself.

I have seen turbos smoke exactly as you describe so I wouldn't rule that out even though it's been rebuilt. You may be smoking while driving but not able to see it. If it were valve seals I would think that you would absolutely be seeing smoke on decel at least. As it is an imported F23A, I would assume it has low miles. If the engine was clean and looked good I wouldn't initially think that it would be the culprit. I have seen 400k+ mile examples that don't smoke a bit. From my experience with aftermarket turbo cars, if it's smoking, 80% of the time it's related to the turbo and/or seals. The fact that you stated a restrictor helped points to that even further.

Have you pulled the plugs to see if any of them are wet? How's your PCV system routed?

xsboredom1

heyo boostedcd5 :p

I really hope its not the turbo since it cost me like $150 to have it rebuilt lol

Plugs looked fine when i swapped them 2 weeks ago. Bone dry. PCV system is two -10 off the valve cover to a v2a catchcan.

I'll try the screw driver drink on the oil pan. I'll be doing an oil change tomorrow anyways so it'll be a perfect time to get some pics and test it

edit:

You may be onto something with the drain and the girdle. Definitely felt something with the screw driver, but there seems to be enough space for the oil to flow, but its always possible. I have an extra pan so I'll have another bung welded a little more over so its more inline with my turbo and i make it more vertical. There was residue on the fitting so that might be some pressure building up in the drain?