Burning oil smell on decel - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


General Miata Chat A place to talk about anything Miata

Reply
 
 
 
LinkBack Thread Tools
Old 06-30-2007, 03:33 PM   #1
Senior Member
Thread Starter
iTrader: (2)
 
SamS's Avatar
 
Join Date: Jun 2006
Location: Wisconsin
Posts: 1,251
Total Cats: 7
Default Burning oil smell on decel

This has been happening for quite some time, my car smells like burning oil when engine braking. It doesn't smoke as far as I can tell, but last year it almost always smoked when the engine was cold after startup. No noticeable power loss or other symptoms. I'm thinking it's something to do with the valves, but who has any other insight before I take the head off?

Thanks
SamS is offline   Reply With Quote
Old 06-30-2007, 08:47 PM   #2
Senior Member
 
Join Date: Dec 2004
Posts: 1,450
Total Cats: -1
Default

How's your PCV system routed?
bripab007 is offline   Reply With Quote
Old 06-30-2007, 09:26 PM   #3
Senior Member
Thread Starter
iTrader: (2)
 
SamS's Avatar
 
Join Date: Jun 2006
Location: Wisconsin
Posts: 1,251
Total Cats: 7
Default

I'm using the standard Miata PCV valve, it works only when I blow in from one side, so that's fine. I just have a breather filter on the other valve cover port though, could that be where my problem is?
Name:  DSC00486Medium.jpg
Views: 43
Size:  82.2 KB
SamS is offline   Reply With Quote
Old 06-30-2007, 09:52 PM   #4
Senior Member
iTrader: (3)
 
Join Date: Apr 2007
Location: Odenton, MD
Posts: 713
Total Cats: 0
Default

im pretty sure you're suposed to route that somewhere and remove the filter because it causes a large vacume leak.
Dow.tom is offline   Reply With Quote
Old 06-30-2007, 10:03 PM   #5
Senior Member
Thread Starter
iTrader: (2)
 
SamS's Avatar
 
Join Date: Jun 2006
Location: Wisconsin
Posts: 1,251
Total Cats: 7
Default

I'm not so sure about the vacuum leak, as it idles fine. I'll find some hose and route it to the intake though, does it go before the turbo inlet?
SamS is offline   Reply With Quote
Old 06-30-2007, 10:09 PM   #6
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,830
Total Cats: 1,786
Default

yeah, on the intake...it could be that the pcv valve is possibly not sealing under higher pressure (you cant blow 9psi) if that is the case then the pressure entering the crankcase might make it hard for the oil to drain out of the turbo and it burns up a tiny bit.
Braineack is offline   Reply With Quote
Old 06-30-2007, 10:11 PM   #7
Senior Member
Thread Starter
iTrader: (2)
 
SamS's Avatar
 
Join Date: Jun 2006
Location: Wisconsin
Posts: 1,251
Total Cats: 7
Default

Quote:
Originally Posted by Braineack View Post
(you cant blow 9psi)
Speak for yourself. :gay:

I'll pick up a 323 gtx PCV valve at work tomorrow, thanks.

It doesn't smell in boost though, only at high vacuum while engine braking.
SamS is offline   Reply With Quote
Old 07-01-2007, 12:14 PM   #8
Senior Member
iTrader: (8)
 
Join Date: Mar 2006
Location: Floriduh
Posts: 882
Total Cats: 0
Default

Valve seals? If you are not running the MAF, then the filter on the driver side of the valve cover isn't a big issue, if you have the MAF then you should reconnect it to the intake tube before the turbo.

On decel, there should be high vacuum sucking the PCV open into the intake, so I'm not sure if a stronger PCV will solve the issue. The GTX PCV is a good idea, anyway.
soflarick is offline   Reply With Quote
Old 07-03-2007, 03:10 AM   #9
Senior Member
iTrader: (1)
 
Join Date: Aug 2006
Location: Illinois
Posts: 1,011
Total Cats: 7
Default

FYI the number on the autozone replacement PCV valve is 2196. This is the number printed on the PCV valve itself. For turbo Miatas use part number 2190. They look the same but the 2190 will function as a check valve when pressure is on the manifold side. The 2196 will not fully seal under pressure. Looking at values in my EMS I show no change in manifold vacuum at idle. I can pull one of the smaller vac lines and see it in map reading.
lazzer408 is offline   Reply With Quote
Old 07-03-2007, 09:22 AM   #10
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,830
Total Cats: 1,786
Default

When you get them at autozone or pepboys or wherever, open teh package and try to blow through it. 9:10 says it won't seal.
Braineack is offline   Reply With Quote
Old 07-03-2007, 01:48 PM   #11
Senior Member
Thread Starter
iTrader: (2)
 
SamS's Avatar
 
Join Date: Jun 2006
Location: Wisconsin
Posts: 1,251
Total Cats: 7
Default

I work at Advance Auto Parts, so I'll get it there with my 20% discount. I'll def try blowing before I go home though.
SamS is offline   Reply With Quote
Old 07-04-2007, 08:12 AM   #12
Senior Member
iTrader: (8)
 
Join Date: Mar 2006
Location: Floriduh
Posts: 882
Total Cats: 0
Default

Do you get a bigger discount by blowing?
soflarick is offline   Reply With Quote
Old 07-04-2007, 02:19 PM   #13
Senior Member
Thread Starter
iTrader: (2)
 
SamS's Avatar
 
Join Date: Jun 2006
Location: Wisconsin
Posts: 1,251
Total Cats: 7
Default

Only if i blow both ways
SamS is offline   Reply With Quote
Old 03-15-2010, 11:14 AM   #14
Senior Member
iTrader: (4)
 
Join Date: Nov 2009
Location: Toronto, ON
Posts: 1,479
Total Cats: 6
Default

Digging up an old thread. Did you ever solve this? I can smell a lot of oil too. I'm wondering if it is from my valve cover breather. I've never used one before having a turbo. Do they smell? It smells like hot oil rather than burning oil.
dgmorr is offline   Reply With Quote
Old 03-15-2010, 11:29 AM   #15
Senior Member
Thread Starter
iTrader: (2)
 
SamS's Avatar
 
Join Date: Jun 2006
Location: Wisconsin
Posts: 1,251
Total Cats: 7
Default

I got rid of the breather and routed it to the intake, I think it helped a little but I'm pretty sure my valve seals are worn.
SamS is offline   Reply With Quote
Old 03-17-2010, 04:54 PM   #16
Senior Member
iTrader: (4)
 
Join Date: Nov 2009
Location: Toronto, ON
Posts: 1,479
Total Cats: 6
Default

I'm noticing the oil smoke is only when the engine is cold and warming up when the oil pressure is high. Does this indicate that I need an oil restrictor?

The smoke clears when the idle and oil pressure drop after the water temps rise closer to operating temps.
dgmorr is offline   Reply With Quote
Old 03-17-2010, 04:57 PM   #17
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,830
Total Cats: 1,786
Default

where is the smoke coming from?
Braineack is offline   Reply With Quote
Old 03-17-2010, 05:05 PM   #18
Senior Member
iTrader: (4)
 
Join Date: Nov 2009
Location: Toronto, ON
Posts: 1,479
Total Cats: 6
Default

It's coming out the exhaust - blue, so it's going through the engine. My engine was perfectly fine before the turbo install.
dgmorr is offline   Reply With Quote
Old 03-17-2010, 05:48 PM   #19
Want fries with that?
iTrader: (3)
 
Join Date: Oct 2009
Location: Twin Cities, Minnesota
Posts: 2,023
Total Cats: -1
Default

Quote:
Originally Posted by dgmorr View Post
It's coming out the exhaust - blue, so it's going through the engine. My engine was perfectly fine before the turbo install.
Oil seeping through turbo seals?
rider384 is offline   Reply With Quote
Old 03-17-2010, 06:08 PM   #20
Senior Member
iTrader: (4)
 
Join Date: Nov 2009
Location: Toronto, ON
Posts: 1,479
Total Cats: 6
Default

Quote:
Originally Posted by rider384 View Post
Oil seeping through turbo seals?
Most likely. No abnormal shaft play. Just wondering if I need a restrictor. Oil pressure is up around 80psi when the engine is warming up. Down to 15-20psi at hot idle.

I think I clicked on the wrong thread when asking this question, ooops
dgmorr is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
OTS Bilstein to motorsports ASN conversion stoves Suspension, Brakes, Drivetrain 5 04-21-2016 04:00 PM
My solution for Oiltemp and Oilpressure input into Megasuirt (MS3) Zaphod MEGAsquirt 41 01-24-2016 01:25 PM
Moroso Air Oil Separator Catch Can Aroundcorner Miata parts for sale/trade 2 10-01-2015 04:20 PM
Low oil pressure after 1.8 swap and new turbo setup JesseTheNoob DIY Turbo Discussion 15 09-30-2015 03:44 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 06:53 PM.