is this blown turbo seals?

[dnhieu]

alright here is the problem i was doing a boost leak test and i have 2 of them. 1. pcv valve and 2. im getting alot of blowby at the crank. i know im getting alot of blow by from the turbo because after i tested at the turbo i tested at the throttle body elbow and there was a HELL of alot less crank pressure then before. from what i understand this means i have blown turbo seals. the part i dont understand is that my 20g barly has any shaft play and there is NO OIL in the intake of the turbo or my intake for that matter. also im only getting like 11hg vaccume and my timing is right on! the only thing i can think of is that im getting so much blowby the turbo seals and the pcv valve that its causing low vaccume. i think thats really low even tho its basically a really bad boost leak. has anyone every seen or herd of anything like this?

thanks in advance tuners
david

btw i dont really get an even pull outta my car. in first gear if i punch it, it will feel like no power then around 3.5k-4k hit will hit HARD. its not like an even pull if you can understand what im saying.

 

[DSM90AWD]

The oil rings on the turbo are meant to contain oil not hold back air pressure, so the pressurized air finding it's way to the crankcase is normal when boost testing at the mounth of the turbo.

Unless you have excessive shaft play or are burning oil, I'd think the turbo fine.

11" Vacume seems pretty poor for a car at sea level. Have you compression/leakdown tested the car? Is it possible that you may have a retarded exhaust cam?

 

[andymoraitis]

David,

I'm with John on the vacuum issue. I'd recommend re-checking the timing marks with cylinder one at TDC. If the marks line up correctly with a straight edge, I'd grab a can of carb and choke cleaner and start looking for vacuum leaks by spraying the vacuum lines while at idle. If the idle changes, she's leaking and that particular line needs to be replaced.

Let us know how it goes,

Andy

 

[dnhieu]

thanks guys for you input....

i checked timing right after i wrote this thread awhile ago. timing is right on and when i checked it with a timing light it was right on also. i dont know if timing can be a tooth or two off and still be at 5 btdc but thats where it is currently at.

i checked the turbo the other day again and its got a tiny bit of up and down and in and out play. i think im just gonna suck it up and pull the turbo off and replace the seals. i have no idea how many miles are on my 20g anyways so it couldnt hurt right?

another thing i noticed is that my high fuel trim is ALWAYS rich. no matter wtf i do its always in the 80% range. i have a bunch of buddies that recently got rid of the maft for this reason but i really think its because of the amount of blow by im getting.

also, i did a compression test a month before i made this post and i got 170-170-170-165 so im thinking my valve stem seals are fine

thanks again guys i really needed someone who really knew there shit to step up and help me with this problem. sorry it took me so long to get back to this post but i didnt even notice it untill i was reading up on how to replace turbo seals.

thanks again
david

 

[oldman]

What was the result of your boost leak test? Doesn't sound linke your done.

 

[dnhieu]

well i can spray soapy water at 25psi and i dont anything but small leaks...

but i know im getting alot of blow by from the pcv valve and when i open up the oil cap i can actually hear the air in the head. im still only getting 11 vacumme and idle and its causing my car to stall ALL THE DAMN TIME!

alright this is gonna sound dumb but i was just reading some threads about low vacumme and someone said the coil pack would case low vacumme ??? is this true? i feel like a jack ass asking that question but thats what someone said in one of there threads...

 

[oldman]

well i can spray soapy water at 25psi and i dont anything but small leaks.....

I find it hard to believe that with noticeable leakage into the crankcase, you're able to pressurize the intake tract up to 25psi. I suspect the reading came from your air compressor regulator, not your boost gauge. BTW many small leaks = big leak.

 

[dnhieu]

man i really dont want to sound like a cocky asshole but i dont look at the guage on my air compressor i look at the boost guage. the guage on the air compressor is always off by at least 5psi. the car will hold 25psi. hell, i think it would hold 30psi if i cranked the air in the air compressor up. maybe im describing the hissing noise im hearing wrong. one thing i am positive about tho is that if i boost leak test it at the throttle body elbow that the noise does go down...

anyways, i guess my small boost leaks which are seriously VERY tiny are causing my high low trims and low vacumme? i have never looked at my vacumme then fixed a boost leak then looked at my vacumme again to see what the readings were before so i dont know if the small leaks can make a HUGE diffrence in my vacumme.

 

[oldman]

If 25 psi is from the boost gauge, you can rule out leaks.

 

[dnhieu]

man im confused now. i seriously boost leak test my car AT LEAST once a week and i see 20psi on the boost guage but i also open up the oil cap and hear air. are you telling me this cant be true?

 

[oldman]

man im confused now. i seriously boost leak test my car AT LEAST once a week and i see 20psi on the boost guage but i also open up the oil cap and hear air. are you telling me this cant be true?

That depends on the pressure set on the compressor regulator, compressor size and the amount of air you hear under the oil cap, keep in mind that you will always have some air escaping the rings even if testing from the TB elbow. What is also missing in your analysis are valve seals.

 

[dnhieu]

OKAY this problem is really starting to piss me off...

boost leak tested again and i have ABSOUTLY NO BOOST LEAKS. i walk over and open up the oil cap there is so much air in the head that it kinda "blows off" as i open the oil cap? im getting so much damn blow by its not even funny. the car itself held 25psi. according to old man this isnt blown turbo seals. the car doesnt smoke at idle or when i get up on it.

i can only think of 3 things...

1.bad turbo seals
2.bad valve stem seals
3.or bad piston rings

i did a compression test AGAIN and got 170-170-170-160 AGAIN. so that rules out bad piston rings. doesnt it also rule out that i have bad valve stem seals? i do now have a little bit of turbo shaft play. more then i would like.

this problem is really making me mad because i cant get a good tune on my car. i think its causing a bunch of rich knock and causing my fuel trims to be peged at 81.2%. also i have replaced my pcv valve with a brand new oem one finally.

please help
david

 

[dnhieu]

also i boost leak tested a friends car this weekend and we tested at 25psi just like my car and i cracked his oil cap and he was getting blow by but not alot. his sounded normal blow by like old man has said earlier in the thread. mine sounded like 100% of the air that was going in was straight up building in the head...

 

[hopeformylife]

This is a complete shot in the dark. I know I don't have half the experiance as most of the guys posting on this thread, but could your homemade boost controler be causing a major problem? Or is the boost controler being installed backwards?

Besides that my only other thought is KISS, try and take aftermarket parts out until you find out what is causing the problem. Maybe check your ECU for leaky caps...... just thinking out loud, it's late.

 

[scottsee]

You know what, I've been chaseing my tail around the same problem you are having dinhieu. I have good compression, 11in/hg vac, spot on timing. I need to replace all of my leaking injector o-rings before going any further with my diag and pinpointing my low vac. But please keep this updated. I'll do the same...

have you tried temperalty removing all of your emission/vac & block off your EGR? Thats what I plan on doing next month to see what happens with my vac and go from there.... If it's magicly better then I'm leaving it and registering it at my grandparents in a county that dosen't require emission testing.. If not then I know its mechanical...

 

[dnhieu]

well for right now im only running off my tial wastegate which is 1bar...

i have been having this problem for awhile now too. when i bought the car it had a big 16g on it and i never pay any attention to the vacumme but at the time i had HUGE boost leaks. i fixed them all and put the 20g on all at the same time. i have no boost leaks what so ever and i have the race setup as far as vaccume lines are concerned...

im really about to just buy a bigger turbo or pull this one off and have it rebuilt. my buddy has a han super 16g. its got a t/3 housing and 20g internals. he wants 400 bucks and hes throwing in a cheap ebay manifold for free. or im thinking about taking the head off and rebuilding it. i think thoes are the only two options i have right now....

 

[DSM90AWD]

Did you ever try the leakdown test?

By "Race Setup" for emission lines do you have your PCV removed or venting to ATM (e.g. not connected to the intake) and is your Valve Cover breather venting to ATM?

 

[dnhieu]

Did you ever try the leakdown test?

By "Race Setup" for emission lines do you have your PCV removed or venting to ATM (e.g. not connected to the intake) and is your Valve Cover breather venting to ATM?

i dont have a leak down tester nor do i know anyone who has one. hell, i dont even know how to use one.

by "race setup" i forgot to mention that i still do have the pcv system still hooked up but everything else is like the "race setup". its routed to a catch can from the valve cover then to the intake like stock.

how much would a leak down tester cost? might be more cost efficient then my current plan of downgrading to a evo 3 16g and if that doesnt work get my spair head re-built and ready to do a head swap....

thanks for the help
david

 

[DSM90AWD]

Summit Racing has a leakdown tester for $65, Harbor Freight has one for $59.. though I've seen these rented for free/little cost from some chain automotive stores. A service station may even do the work for you for near the cost of the unit (but what fun would that be ).

If I understanded you correctly, your PCV was still installed in the valve cover but is routed to a catch can? If it is still connected to the head and is stuck open, then that could also explain the excessive pressure in your crankcase.

But as I said before, it's totally normal for boost to flow past the oil seals in the turbo to the crankcase when pressure testing at the compressor inlet

BTW.. Leakdown Tester VFAQ

 

[dnhieu]

my pcv is just like stock. my catch can is routed from the breater side of the valve cover to the intake just like stock. sorry for the confusion.

okay i have so much crank pressure while being tested at 25psi that when i crack the oil cap it makes a PPPPSSSSHHHHHH sound. it was so bad that excess oil around the cap splattered all over the valve cover and cam gear cover.

what can cause blow by ingeneral so i can try to narrow down whats causing this problem...

edit: also what if i get bad numbers on a leak down test? what parts on my car can potientially be bad (besides just piston rings)?

thanks again
david

 

[tsunari]

Here's my experience . . .

I have always done boost leak tests after the compressor . . . usually on the hot-side of the intercooler. Tonight I tried doing one @ the compressor inlet and could barely build 7psi (usually aim for 25+).

Turns out, the air seemed to be seeping into the center cartridge of the turbo and down the oil return line and pressurizing the case. Took the oil cap off and there was a decent bit of air coming out. . . and this is on a PTE GT30r that is maybe 6 months old.

Re-hooked everything up to the hot-side of the IC and all was normal . . . just a slight sound of air from the oil filler, but nothing serious.

 

[dnhieu]

alright getting back to this thread....

did a compression test and the numbers were not all that good or the same 160-160-160-145. found out that the #1 cylinder had a bad arching issue witht he coil pack resulting in lower compression numbers i believe.

timing is right on! hell i tripple checked this and it was right on every time.

next im gonna find out and see if my throttle body is closing all the way and run a boost leak test at the intercooler piping again instead of the turbo inlet. if the air sound goes down im gonna blame it on a bad turbo. if the throttle body is bad im just gonna have to replace it again...

 

[andymoraitis]

David,

In the midst of all of this, don't forget to run the motor at idle and spray carb cleaner on the vacuum lines to see if the idle changes. I know you've got a lot going on, but keep the simple stuff in mind.

Let us know what turns up,

Andy

 

[dnhieu]

actually i forgot all about it man. nothing against spraying carb cleaner around the intercooler piping, and throttle body but wouldnt something show up while i was spraying my piping and throttle body with soapy water at 25psi? the only thing that leaks is the bov and it isnt bad enough to cause low vacumme.

dont by any means take that statement the wrong way. just trying to see your point better. also what else should i be spraying down with carb cleaner?

also thanks for the help
david

 

[andymoraitis]

David.

No worries and no offense taken. You're referring to testing for boost leaks and I'm talking about vacuum leaks. Vacuum leak tests need to be done with the motor running at idle and warmed up. It's a matter of spraying carb and choke cleaner around all of your vacuum lines on the intake manifold, TB, brake booster, FPR, etc. You don't go near the intercooler pipes. If you detect a stumble or a change in idle, you need to replace that particular line or re-check the connection.

Know what I mean Vern?

Andy