Is my motor done?

[SMatyac]

I picked up my s14 the other day and it has an sr20det with a gt2871r .86 ar, and has 880cc injectors, and it ran like a champ.
On the way home i want very hard on it at all, but it started shooting an oily mist out of the BOV, and then it started missfiring when it hit over 15psi. it doesn't smoke unless it misses. Occationally it will hit full boost, i can floor it and it runs awesome.
I took it to a shop, they pulled off the oil filler cap and it had a pretty strong pump of air coming out of the hole.
The shop said it could possibly be the headgasket, but it could also be my bottom end.
My car doesn't have an oil restrictor on the turbo, and it doesnt have a catch can, is it possible the TPS sensor only sometimes works fine, or do you think the pistons are fried?

[jdm213]

u answered 1 of ur questions.. if it pulls hard and runs awesome then ur bottom is good. if u wanna make sure a compression test is the way to go . if all is good try a leak down test and check the head . u may have some form of blow by , by uneven head pressure . trouble shoot

[SMatyac]

Well it only runs good occasionally, but i guess if the pistons were fried i guess it would never run good.
Could it have been overheated and the head be warped right now?

[fliprayzin240sx]

First off, did you just get this car? What was used for tuning and who tuned it? Is the car tuned for the setup? Either way, do a compression check and see if what the compression is at. Also, what engine is this, S13 or S14 SR? Is the line from the valve cover still running into the intake tract?

[SMatyac]

Yeah I just got it, batlground tuned it using the apexi power fc standalone.
It was tuned for the same setup but different exhaust manifold.
S13 sr, and yes it has the line going from the valve cover to the turbo intake tract, but it doesnt have a catch can.

The only reason I don't think it's the tune is because sometimes it runs great, and it ran great when I first got it.
It usually does the best when I don't hit full boost for about 20min of driving, or the first time I jump on it once it's warmed up.

[SMatyac]

Well installed a catch can, and it seems to be running perfect now. so i guess thats all i needed.
I still don't know why its blowing air out of the oil fill hole when the cap is off though. but it doesn't seem to be affecting performance.

[jamg]

Well installed a catch can, and it seems to be running perfect now. so i guess thats all i needed.
I still don't know why its blowing air out of the oil fill hole when the cap is off though. but it doesn't seem to be affecting performance.

you need to vacuum it right.

[SMatyac]

Do you think the vacuum lines are ran wrong?

[zneubauer]

u answered 1 of ur questions.. if it pulls hard and runs awesome then ur bottom is good. if u wanna make sure a compression test is the way to go . if all is good try a leak down test and check the head . u may have some form of blow by , by uneven head pressure . trouble shoot

yeah I agree ^^ and also you might want to run a catch can or get a tune.

[SMatyac]

Well i just installed a catch can, and it has already been tuned. So it runs awesome now, im just figuring out the whole air out of the oil fill hole now.
It seems like i'm getting a decent amount of blow by.

[SMatyac]

Well i read up a lot on the issue i'm having, and many people suggest blocking off the pcv valve and running the catch can to atmosphere, so i did it and it doesn't suck any oil in the catch can anymore. but for some reason there isnt much air coming out of the catch can, but when i pull off the oil fill cap it sounds like exhaust is coming out of it, and there is still a ton of air coming out of it, almost as much as there would be from the exhaust.
I still have no power loss, and still no smoke (A tad bit of black smoke under full boost, but thats just fuel and im catless) so should i worry about it?

P.S. i did a compression test and there was a little oil in the first 2 spark plug wells, so that bit of oil fell in the cylinders, and it wasnt fully warmed up, and not WOT, so i know i did a few things wrong, but it still made 145-140-135-140. and when i put a tad bit of oil in the 3rd cylinder, it jumped to 145
Im going to do a retest and do everything better, when its warmed up, and at WOT, but just to give you an idea of what it did.

[jr_ss]

Your bottomend is fine. You need to put a restrictor in the turbo feed line as your probably blowing out the oil seals. BB turbos do not like high feed psi or huge volumes of oil.

[SMatyac]

So that would cause the pressure in the valve cover?

Because i have been freaking out over this stupid thing.
I don't know why its doing that, and i really don't wanna keep driving it and have something wrong, then completely blow up the engine.

And also, why would air only come out of the oil fill cap when its off, and not out of the catch can which is routed to atmosphere. Are they not connected in some way?

Sorry for all the questions, this damn engine is just really confusing me.

[jr_ss]

You're going to have air coming from the oil fill hole, it is inevitable. You have a large void in the front of the motor that lets crankcase pressure escape from that area up into the head/VC. Your pistons are moving up and down pushing that air out. Don't worry about it so much. If you have enough air to blow your oil dipstick and oil out of that tube, then you have too much blow by and the engine needs some help.

Pictures help too... Post a picture of your turbo/intake area and your VC/intake manifold.