Blue-ish smoke from exhaust - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

gunmetalrps · 02-12-2009, 06:54 PM

i just wanted some feedback.

its a sohc KA. had a rebuilt, resurfaced head, new valve seals/guides about March 08. also new headgasket. its not blowing a lot of smoke only when im at full throttle around 5.5k-7.5k rpms. not overheating AT ALL. still pulls strong. if i drive normal theres no smoke at all. when it does smoke its kinda blue-ish. im thinking piston rings since the block is at about 190xxx. but what about 02 sensor or fuel mixture running rich. i know it cant be the valve seals or head gasket. also, it doesnt seem to be losing much oil( even though the oil pan is kinda leaking oil)

any ideas?

ATLspeed · 02-12-2009, 07:05 PM

i say it may be your rings, check compression

is the CEL on?

Alpha Residence · 02-12-2009, 07:08 PM

could be something as simple as bad spark plug gaskets as well.

gunmetalrps · 02-12-2009, 07:12 PM

spark plug gaskets? can you go more in-depth?

The Chad · 02-12-2009, 07:30 PM

He means the rubber rings/gaskets that run along inside the Valve cover. They usually come in a set with a new valve cover gasket. I honestly would say piston rings though. I'm having the same prob, but mine does a quick puff on start off too.

*fliprayzin240sx* · 02-13-2009, 03:56 AM

Do a compression, better yet, leak down test to see if its the rings...

rex2sx · 02-13-2009, 08:50 AM

Dont do a compression test. Compression test is for compression rings. Leakdown test would work better. But since you said the head as new guides and seals the only thing i can think of is the tube seals. Ill check around for ya.

xsparc · 02-13-2009, 10:50 AM

spark plug gasket???? um ok...

on a SOHC with what you say "blue smoke... high rpm", it means 1 or 2 things....

piston rings and/or stem seals

and since you said you have new stem seals then that leaves only the rings.

redpotatoes · 02-13-2009, 11:44 AM

If there is not much smoke it might be your valve seals. Even if they were done in march 2008, maybe something is wrong there...

02-12-2009, 06:54 PM	#1
gunmetalrps Leaky Injector Join Date: Sep 2007 Location: socal Age: 38 Posts: 61 Trader Rating: (0) Feedback Score: 0 reviews	Blue-ish smoke from exhaust i just wanted some feedback. its a sohc KA. had a rebuilt, resurfaced head, new valve seals/guides about March 08. also new headgasket. its not blowing a lot of smoke only when im at full throttle around 5.5k-7.5k rpms. not overheating AT ALL. still pulls strong. if i drive normal theres no smoke at all. when it does smoke its kinda blue-ish. im thinking piston rings since the block is at about 190xxx. but what about 02 sensor or fuel mixture running rich. i know it cant be the valve seals or head gasket. also, it doesnt seem to be losing much oil( even though the oil pan is kinda leaking oil) any ideas? __________________

02-12-2009, 07:05 PM	#2
ATLspeed Zilvia Addict Join Date: Jan 2007 Location: Eden, MD, USA Age: 38 Posts: 921 Trader Rating: (14) Rides Gallery: ATLspeed Feedback Score: 14 reviews	i say it may be your rings, check compression is the CEL on? __________________ 93 s13 Vert - 2jz/cd009 -- parted/sold 95 Supra Turbo

02-12-2009, 07:12 PM	#4
gunmetalrps Leaky Injector Join Date: Sep 2007 Location: socal Age: 38 Posts: 61 Trader Rating: (0) Feedback Score: 0 reviews	spark plug gaskets? can you go more in-depth? __________________

02-13-2009, 03:56 AM	#6
fliprayzin240sx Man w/ CTSV & a Car Seat Join Date: Aug 2002 Location: Tampa Posts: 17,998 Trader Rating: (19) Rides Gallery: fliprayzin240sx Feedback Score: 19 reviews	Do a compression, better yet, leak down test to see if its the rings... __________________ If you think Zilvia has too many assholes... CLICK HERE!!!

02-13-2009, 10:50 AM	#8
xsparc Zilvia Junkie Join Date: Dec 2002 Location: san diego area - esco Posts: 461 Trader Rating: (0) Feedback Score: 0 reviews	spark plug gasket???? um ok... on a SOHC with what you say "blue smoke... high rpm", it means 1 or 2 things.... piston rings and/or stem seals and since you said you have new stem seals then that leaves only the rings. __________________ No... no one stole my interior... its safely in my garage...

02-12-2009, 07:08 PM	#3
Alpha Residence Join Date: Feb 2009 Location: VS.NY Age: 43 Posts: 38 Trader Rating: (1) Feedback Score: 1 reviews	could be something as simple as bad spark plug gaskets as well.

02-12-2009, 07:30 PM	#5
The Chad Zilvia Addict Join Date: Feb 2007 Location: Richmond, VA Age: 44 Posts: 943 Trader Rating: (0) Feedback Score: 0 reviews	He means the rubber rings/gaskets that run along inside the Valve cover. They usually come in a set with a new valve cover gasket. I honestly would say piston rings though. I'm having the same prob, but mine does a quick puff on start off too.

02-13-2009, 08:50 AM	#7
rex2sx Zilvia Member Join Date: Feb 2009 Location: pennsylvania Age: 34 Posts: 158 Trader Rating: (0) Feedback Score: 0 reviews	Dont do a compression test. Compression test is for compression rings. Leakdown test would work better. But since you said the head as new guides and seals the only thing i can think of is the tube seals. Ill check around for ya.

02-13-2009, 11:44 AM	#9
redpotatoes Zilvia Member Join Date: Apr 2005 Location: Qc Posts: 219 Trader Rating: (2) Feedback Score: 2 reviews	If there is not much smoke it might be your valve seals. Even if they were done in march 2008, maybe something is wrong there...