i have been trying to diagnose this smoke that comes out of my exhaust for about 3-4 weeks and I have narrowed it down to a few problems. I knew It only happens everyonce in awhile.

After driving today I think it only happens after i drive it for over 15mins getting on it(Driving Hard). I will pull over and after a minute or two, it starts to smoke. the interesting part is After 10 mins of idleing and smoking out of the exhaust, it will go back to normal. I did this 2 times and I had the same results. On my way home, I did not drive it hard at all. I let it idle for 5 mins after that and i never saw any smoke...

I think it is b/c when i get on it, somehow the block and the head separate, b/c of Pressure, and a bit of coolant gets in the cylinders. once i stop, it starts to burn it off and smoke. Maybe my headgasket is letting a bit of coolant in or my ARP head studs are not torqued down enough. It is like a white/blue smoke and it only does it after i get on it. (I torqued them down after 1500miles to 75lbs)

At first i thought it was oil getting backed up in my return line... but after i diagnosed it the first time i poured another quart in my engine and got no different results.(the first time the oil was low enough so that the return tap on the pan was not covered by oil :: the second time it was filled above the return tap,therefore covering the tap by oil)

sorry for the long post. Please let me know if i could be leaking threw my headgasket only under boost and not under normal driving conditions. I have a stock head gasket on there and i am running 18psi.

Thanks-
Corey

 

warped deck or head?

 

some other things that i have done...

I drained about a quart of coolant out of my radiator today and the color looked ok. I have changed my oil every 1000 and have not noticed any coolant in the oil.

I did a compression test and came out to
180 in cyl. 1
175 in cyl. 2
170 in cyl. 3
170 in cyl. 4

Leakdown:
5% in Cyl. 1
6% in Cyl. 2
8% in Cyl. 3
9% in Cyl. 4

Help would be greatly appreciated.

Corey

 

It could be alot of things. If you have retorque the ARP's they are most likely fine. If you are sure its white/blue smoke then you might have two problems at once. Do a compression test/leak down test. If you head is in questionable condition then it might be your valve stem seals with the oil leak, and your headgasket might have a hairline crack. Its always hard to diagnose where a car is leaking from if the prelimary checks have been made.

 

what about leaking oil seals on the turbo? How do your charge pipes look?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Scott - 93HB Si &raquo;</TD></TR><TR><TD CLASS="quote">what about leaking oil seals on the turbo? How do your charge pipes look?
</TD></TR></TABLE>

The charge pipes look good. I took them off last week and painted. Did not see anything out of the ordinary.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">It could be alot of things. If you have retorque the ARP's they are most likely fine. If you are sure its white/blue smoke then you might have two problems at once. Do a compression test/leak down test. If you head is in questionable condition then it might be your valve stem seals with the oil leak, and your headgasket might have a hairline crack. Its always hard to diagnose where a car is leaking from if the prelimary checks have been made.</TD></TR></TABLE>

If it were the valve stem seals, won't it smoke all the time?

 

Bump for the night crew. I know it is long, Please read tho.

 

i was thinking valve seals also, because on old v8's they would smoke on warmup and once the seals heated up they expanded and it wouldnt smoke anymore..

 

similar problem im having. i cant figure it out.

 

i would lean towards valve seals. they do not leak all the time just like your discribing, but they do tend to leak at first start up, so if there is no smoke then, it may be the headgasket.
now, a bad pcv valve can allow oil to build up in the return line when running a motor hard. then at idle, the vacuum will suck the oil out of the line. this is at least a cheap thing to check/replace.

 

My guess would be turbo seals. There doesnt have to be oil in the charge piping/compressor housing. Its just as likely to be leaking past the exhast side seal. Try this: if your car starts smoking at idle, bring the revs up to 1500 or so. Just enough to get the turbo spinning. It usually will stop the smoking, if its the exhaust side seals.

 

I agree with ehhaust side turbo seal

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rioninja &raquo;</TD></TR><TR><TD CLASS="quote">My guess would be turbo seals. There doesnt have to be oil in the charge piping/compressor housing. Its just as likely to be leaking past the exhast side seal. Try this: if your car starts smoking at idle, bring the revs up to 1500 or so. Just enough to get the turbo spinning. It usually will stop the smoking, if its the exhaust side seals.</TD></TR></TABLE>

This can be a good test. I will let everyone know if this works. Thanks Man.

Corey

 

i'm having the same exact problem as you. each time i went into boost, my car will smoke then after letting it idle for awhile the smoke goes away.

if i drive hard say 7000rpm there will be a lot of smoke and it is embarrasing. but if i only boost till 4-4.5k rpm it won't be as huge. BUT if i just drive it at a max 3000rpm without going into boost then i don't see any smoke at all.

during cold startup and idling doesn't produce any smoke only when it hit boost.

please update us if found the source of the smoking. by the way, what viscosity oil are you using?

 

This is exactly what is happening to me. Turbo needs rebuild I guess?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by _Endless_ &raquo;</TD></TR><TR><TD CLASS="quote">
by the way, what viscosity oil are you using?</TD></TR></TABLE>

I am using 10w30

 

so did you found out what the problem was?

 

I would like to know too....How did that test work out? Also, what if you rev it at 1500rpm and it still smokes

 

I changed my oil to Mobil1 10W30 and the smoking stopped. I was using Valvoline Durablend before. I guess my turbo didn't like that stuff very much.