Dear diary...

[udntknw]

It started in December of 06 when I bought my speed... Blah blah blah. It's been a couple years now since I've been tuning it and changing things up on a regular basis. Leading up to a BUDGET forged motor. But more on that later...

Later has come... I purchased a Speed3 from Kentucky with a known blown motor. I had previously picked up a set of stock pistons and rods when i thought my original motor was on its way out. got the car for a good enough deal hoping it was just a cracked ringland of sorts and i could just pop and drop the new parts in to freshen it up and flip her. After diving into the engine and getting the head, a crack in the sleeve of cyl#3 reared its ugly head. rather disappointed i started looking at new blocks vs used block + machining + pistons. Ran across a set of used Wiseco pistons with Eagle rods for a good price and decided that with those and a used block i could build a budget forged motor on the inexpensive side and drop said forged engine into my car. Swap my current engine with Flip car and off she goes. everything came together relatively well and ended up selling the flip car to a dealership and having a forged bottom end in my car. also scored some goodies off the donor car and sold some others.

Right now I'm having a couple issues, can't decide how related to each other they are.

So now I'm on my built motor, having a random yet controllable smoking issue. Need some more ears/eyes to bounce ideas off of.

Have searched and searched, can't find a related issue.

I'm getting smoke from the exhaust, ONLY if I'm light throttle, high vacuum cruising (ie. 2nd gear through a school zone at 15mph) as soon as I give it anymore throttle it goes away.

I have a catch can (w/ check valve), there is no oil in the charge pipes, no smoking under boost, no smoking idle, only while cruising in high vacuum.

Compression at 250 miles was 185, 185, 185, 190.
Compression now is 185, 140, 185, 190.

I've also got a "knock" sound coming from the motor idle. I reused the stock injector seals (a sin i know) but i hope the compression/knock are both from said seals. But looking for other ideas behind the smoking.

[Spec]

It's smoke from oil for sure right?

[mituc]

I think the smoke may be either from oil coming from through PCV (PCV stuck open?) or exhaust valve seals. If it was the rings or injector seals the smoking should happen under boost.

[udntknw]

Originally Posted by Spec It's smoke from oil for sure right?

For sure oil.

Originally Posted by mituc I think the smoke may be either from oil coming from through PCV (PCV stuck open?) or exhaust valve seals. If it was the rings or injector seals the smoking should happen under boost.

That's what I was thinking on the rings. The PCV may be bad, not sure though. The OCC does have a check valve as well.
What would be the easiest way to check the Pcv? Pull it off the OCC and try to blow through it?

[anavrinIV]

When my injector seals were failing the ONLY symptom was high levels of WOT knock. No noise, compression was fine, ran great, no smoke. Not even any soot at the injectors. Usually injector seals failing is noticeable under high-er throttle input.

[Spec]

Originally Posted by udntknw For sure oil. That's what I was thinking on the rings. The PCV may be bad, not sure though. The OCC does have a check valve as well. What would be the easiest way to check the Pcv? Pull it off the OCC and try to blow through it?

you can test it if you can blow harder than the cracking pressure of the check valve. If you can, call me. It should only come out one way but, I would think you'd be popping dipstick too if it were.

I'd be doing a leak down test and find where you're losing air.

[torquemaniac]

My guess : when the engine is under vacuum (no boost), the exhaust pressure may be very low, so the potential for the oil to get past the seal (turbo) is there

At idle, there is no smoke because the oil pressure may be too low (low rpm, low pump pressure), but at light throttle the oil pressure should increase with rpm, just enough to past the seal (thank to the low exhaust manifold pressure)

Dont know if im clear...no time to write more...

[udntknw]

Originally Posted by torquemaniac My guess : when the engine is under vacuum (no boost), the exhaust pressure may be very low, so the potential for the oil to get past the seal (turbo) is there At idle, there is no smoke because the oil pressure may be too low (low rpm, low pump pressure), but at light throttle the oil pressure should increase with rpm, just enough to past the seal (thank to the low exhaust manifold pressure) Dont know if im clear...no time to write more...

im pickin up what your putting down. I had thought about whether or not the pressure differential between hot/cold side could have been causing the smoking. The turbo does have a restrictor bolt in as well. maybe with the increased oil pressure at higher RPM it very well could be leaking past the seals.

Originally Posted by Spec you can test it if you can blow harder than the cracking pressure of the check valve. If you can, call me. It should only come out one way but, I would think you'd be popping dipstick too if it were. I'd be doing a leak down test and find where you're losing air.

Ill pull both lines off the catch can and check that both valves are working and go from there. i dont have a leakdown tester not a compressor at home. but i may be able to pick up a tester and use somone elses compressor.

Originally Posted by anavrinIV When my injector seals were failing the ONLY symptom was high levels of WOT knock. No noise, compression was fine, ran great, no smoke. Not even any soot at the injectors. Usually injector seals failing is noticeable under high-er throttle input.

I figured for now ill throw a new set of stock injector seals since they are cheap enough to throw away if i have to pull them again due to the problem not being fixed. id hate to seat a good set of seals and not be able to reuse them if i have to pull it back apart.

[udntknw]

update:

Compression test this morning... made the mistake of only checking cylinder #1 (for reference) and cyl#2 to verify the compression was still low. cyl1 185psi, cyl 2 145psi.

Cap of oil into #2 resulted in 150psi. WOOHOO! (right?) leaning towards seals.

I happily pulled manifold and injectors to replace the seals with the CP-e seals i got from a fellow Nator that replaced his when he rebuilt. now i know CP-e doesn't recommend reusing the seals, but i seemed to find enough people that has reused them without issues. However, that may be a "reuse in the same car might be ok" but being a different car they could have crushed to a point on the previous car that they wont seal on mine.

immediately following the change, i tested again.
190, 150, 160, 190... WTF?! Maybe a good heat cycle will help them seal up right? No.

same results. dump a cap of oil in 2 & 3...
cyl2 now jumps to 175 and 3 jumps to 200.

the ticking/knocking sound that i presumed to be from leaking seal is also gone now...

either i have managed to fail these compression tests or maybe i failed the wet test before i changed seals, or maybe i just need to stop trying to half ass fix things when i have no budget to and just wait till im able to do it right.

for now... i give up.

im attaching pictures of the head to get opinions if the seals were leaking or not.

edit: im also getting random knock in random places in the WOT pulls (heat cycle) after i put seals in.

[udntknw]

been quite a bit since any update...

all smoking has come to a halt. it does appear that all was being caused by a shot turbo. was rather surprised at how much play in the shaft there was and how much oil was in the elbow off the turbo.

as of today, i have installed a GT2871R and am currently tuning with it. i havent done a comp check in a while and at this point i dont think i really want to know. car is still pulling hard and seeing good progress in numbers with the new turbo.

still no new injector seals although that should change here in the near future.

running into some tuning woes with WGDC that i had run into when doing a load tune prompting me to give up on the load tune. for whatever reason the WGDC wont hit its target in the higher RPM, boost target also not being met.

[anavrinIV]

Originally Posted by udntknw as of today, i have installed a GT2871R and am currently tuning with it. i havent done a comp check in a while and at this point i dont think i really want to know. car is still pulling hard and seeing good progress in numbers with the new turbo.

I had that same theory for a while. Then I did the tests and all came back bad. better to know early than blow it all to pieces.

[udntknw]

Originally Posted by anavrinIV I had that same theory for a while. Then I did the tests and all came back bad. better to know early than blow it all to pieces.

Yeah, I really should. But until I get seals that actually seal, there's still too many variables/potentials for leaks.
Hopefully oil consumption is minimized now that the turbo isn't eating it for breakfast.