Supra Forums banner

1 - 20 of 20 Posts

·
Registered
Joined
·
223 Posts
Discussion Starter · #1 ·
Well i have read a ton of threads about valve stem seals and piston rings, but alot of mixed answers and opinions come up. I just want to know FOR SURE whats making my car smoke before i work on it. Im pretty sure its valve stem seals since it puffs on startup and puffs from stoplights on occasion but there are other symptoms that are making me weary. Whenever i floor it through a gear then shift and cruise a puff comes out. I opened the oil fill cap and no oil or smoke comes out and there is no oil on the tip of the spark plugs so thats good. I need to compression test it but do the autozone read accurate or should i go to sears?
 

·
Republican
Joined
·
8,421 Posts
okk... here is the answer..

Smoke at startup or on decel (5 or 6 speed): 99 percent of the time it's valve guide seals
Smoke after idling for awile (stoplight or something): 99 percent of the time turbo seals
 

·
Registered
Joined
·
967 Posts
Ckanderson said:
okk... here is the answer..

Smoke at startup or on decel: 99 percent of the time it's valve guide seals
Smoke asfter idling for awile: 99 percent of the time turbos seals

you mean smoke after idling for a while and just leaving it idle? I thought after it idles for a while and you blip the throttle, smoke indicates that its the valve stem seals?
 

·
Republican
Joined
·
8,421 Posts
Nope... if it idles for awile (long stoplight or in line at a drive thru) and you blip the throttle it's 99 percent chance it's turbo seals.. (oil makes it past the seals, and burns when you give it some gas)
 

·
Boost Junkie
Joined
·
12,670 Posts
It's valve stem seals. I had the exact same problem when my car had 99k on it.


Steve K.
 

·
Republican
Joined
·
8,421 Posts
^Just because you had the "exact same" problem DOESNT mean that thats the ONLY solution. Thats why I said 99 percent of the time. It might be his valve stem seals (an easy fix) or it could be his turbo's (a not so easy fix) or it could be other things. Make sure you check out all potential causes before deciding it's just one thing. EATHER WAY, I'd still replace your valve stem seals... easy prevetitive matnence there! :bigok:
 

·
EchoDeDupra
Joined
·
4,122 Posts
easy????.... :wtflol:
 

·
feeding your habit
Joined
·
4,015 Posts
honda_s2001 said:
you mean smoke after idling for a while and just leaving it idle? I thought after it idles for a while and you blip the throttle, smoke indicates that its the valve stem seals?

???? :sadwavey:

no. This is indicitave of bad stem seals as well.

I know firsthand, my car did this and after the stem seals were done, no more smoke.

Just to add more confusion, the turbos have no "seals". They have a carbon ring that is supposed to prevent oil from going by the shaft. The turbo sees no oil pressure internally. Oil comes in at whatever pressure, but it just dumps onto the shaft and then flows right down the drain. The key word is dumped, it just flows over the shaft and down the large diameter drain. The drain is large diameter just for that reason - so there is no oil pressure in the turbo. The turbo needs oil, but it is the same idea as a slinger system... it just gets oil thrown onto the shaft and that lubes the journal bearings. (no there is no slinger in the turbo)

-M
 

·
Registered
Joined
·
223 Posts
Discussion Starter · #12 ·
My car has 93k on it and i know its not my turbo there is no oil in the ic pipes. So how would you know if it was piston rings? Its sounding like im going to have to replace those valve stem seals
 

·
Banned
Joined
·
4,144 Posts
If you're single turbo equiped, check that the oil supply is no bigger than a -3 and a -10 for the return, alos ensuring that it is all clocked to a 6 and 12 position. It solved my oil issues.

Eric
 

·
Mid-life Realization!
Joined
·
2,530 Posts
turbosupe said:
My car has 93k on it and i know its not my turbo there is no oil in the ic pipes. So how would you know if it was piston rings? Its sounding like im going to have to replace those valve stem seals
If it was like my car, I could let it sit idle and no smoke, blip the throttle and dense white smoke would come billowing out. If you do a compression test, it should help show if rings are a potential issue (a leakdown may then be in order). Chances are though, that like many have already said, valve seals are a more likely cause of you smoke.

Brad
 

·
"Philzilla"
Joined
·
694 Posts
turbosupe said:
My car has 93k on it and i know its not my turbo there is no oil in the ic pipes.
Not necessarily true. In theory, the compressor-side seal could be fine, but the turbine-side seal could be leaking.

turbosupe said:
So how would you know if it was piston rings?
You'd need to do a leakdown test on the engine.
 

·
Space for sale
Joined
·
983 Posts
Ckanderson said:
okk... here is the answer..

Smoke at startup or on decel (5 or 6 speed): 99 percent of the time it's valve guide seals
Smoke after idling for awile (stoplight or something): 99 percent of the time turbo seals
:werd:

My turbo seals are going, and it does smoke when i am either at a stop light or when my turbo timer is on after i leave the car.
 

·
Registered
Joined
·
967 Posts
Lintrix said:
:werd:

My turbo seals are going, and it does smoke when i am either at a stop light or when my turbo timer is on after i leave the car.
just at idle w/o blipping the throttle?
 

·
Premium Member
Joined
·
4,972 Posts
Let me try to clarify...

If your car smokes after a long drive at constant speed or after idling a long time, it is likely your turbo seals, but you may want to replace your PCV valve as it may be sticking.

If your car smokes when you start it up and (if it's gotten worse) when you leave a stoplight, etc. then it is likely the valve stem seals.

If your car smokes under WOT then it could be your rings. (or turbo seals if accompanied by the symptoms listed above.)
 

·
Registered
Joined
·
967 Posts
RSA Supra said:
Let me try to clarify...

If your car smokes after a long drive at constant speed or after idling a long time, it is likely your turbo seals, but you may want to replace your PCV valve as it may be sticking.

If your car smokes when you start it up and (if it's gotten worse) when you leave a stoplight, etc. then it is likely the valve stem seals.

If your car smokes under WOT then it could be your rings. (or turbo seals if accompanied by the symptoms listed above.)

do you mean idling and it starts to smoke on its own or idling and you blip the throttle? I get smoke on startup (most likely seals) and when I blip the throttle, a few seconds later smoke will come out (if I hold the throttle, ill get that initial smoke but it will cease) The longer I let it idle, when I blip the throttle, the more smoke will come out.
 

·
Republican
Joined
·
8,421 Posts
Dude... you keep asking the same question... its VERY hard to diagnose a car over the internet. Come to Vegas 05 and ill tell ya whats wrong.. ;)
 
1 - 20 of 20 Posts
Top