Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Go Back   Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum > General > Tech Talk > Engine Tech

Engine Tech Technical discussion related to all relevant engines such as KA, SR, RB, CA, 2JZ , L24/26/28, VG, VQ, and LSx series.


Reply
 
Thread Tools Display Modes
Old 08-06-2013, 12:44 PM   #1
shayandude
Zilvia FREAK!
 
Join Date: Feb 2013
Location: louisiana
Posts: 1,184
Trader Rating: (20)
shayandude is an unknown quantity at this point
Feedback Score: 20 reviews
Question 10:1 AFR at idle all of a sudden...?

all of a sudden toda yon the way to work once car was fully warmed up and the temp gauge was in the middle the afr starting dropping at the red light, and at idl the car was between 10:1- 10.7:1
it stayed this way and hasent changed. its a aem wideband sr20 blk top
shayandude is offline   Reply With Quote
Sponsored Links
Old 08-06-2013, 12:52 PM   #2
di-devol
Zilvia FREAK!
 
Join Date: Jun 2010
Location: Woodinville
Age: 39
Posts: 1,412
Trader Rating: (5)
di-devol will become famous soon enoughdi-devol will become famous soon enoughdi-devol will become famous soon enoughdi-devol will become famous soon enough
Feedback Score: 5 reviews
Checked for popped coupler, most likely a boost leak.
__________________
di-devol is offline   Reply With Quote
Old 08-06-2013, 03:20 PM   #3
Croustibat
Nissanaholic!
 
Join Date: Aug 2011
Location: France - Toulouse
Age: 41
Posts: 1,851
Trader Rating: (0)
Croustibat is an unknown quantity at this point
Feedback Score: 0 reviews
If you have a BOV, it is leaking. remove it.
Croustibat is offline   Reply With Quote
Old 08-06-2013, 03:22 PM   #4
shayandude
Zilvia FREAK!
 
Join Date: Feb 2013
Location: louisiana
Posts: 1,184
Trader Rating: (20)
shayandude is an unknown quantity at this point
Feedback Score: 20 reviews
I checked all the couplers. Didn't look for vacuum leaks and yeah I got a hks bov . Think it's loose?
shayandude is offline   Reply With Quote
Old 08-06-2013, 06:03 PM   #5
fliprayzin240sx
Man w/ CTSV & a Car Seat
 
fliprayzin240sx's Avatar
 
Join Date: Aug 2002
Location: Tampa
Posts: 17,998
Trader Rating: (19)
fliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfection
Feedback Score: 19 reviews
Send a message via AIM to fliprayzin240sx
Pressurize the system, you got leak somewhere or you have a bad water temp sensor.
__________________

If you think Zilvia has too many assholes...
CLICK HERE!!!
fliprayzin240sx is offline   Reply With Quote
Old 08-06-2013, 07:51 PM   #6
OnTheChip
Zilvia Junkie
 
OnTheChip's Avatar
 
Join Date: May 2013
Location: Burgaw, NC
Posts: 311
Trader Rating: (0)
OnTheChip is an unknown quantity at this point
Feedback Score: 0 reviews
Since it's going rich, I suspect either a faulty CLT (as suggested by flip), or possibly a leaky injector.
OnTheChip is offline   Reply With Quote
Old 08-06-2013, 08:20 PM   #7
shayandude
Zilvia FREAK!
 
Join Date: Feb 2013
Location: louisiana
Posts: 1,184
Trader Rating: (20)
shayandude is an unknown quantity at this point
Feedback Score: 20 reviews
Hey guys, thanks for the posts, I got home little ago, and with help of a bud, we pulled off the rail, and injectors aren't leaking, and looked good. Checked for vacum leaks and could not find anything. Of course we don't have a system, it was visual and feeling around. Is that sensor same as the CTS or different if so, I've already replaced that about a month ago. My buddy suggested changing out the plugs, they have around 400 miles on them so I don't know. Any other ideas? Oh from work to home which is around 10 miles it literally drank 1/4 tank. It's bad. Crusing, idling its all 10:1
shayandude is offline   Reply With Quote
Old 08-06-2013, 08:47 PM   #8
fliprayzin240sx
Man w/ CTSV & a Car Seat
 
fliprayzin240sx's Avatar
 
Join Date: Aug 2002
Location: Tampa
Posts: 17,998
Trader Rating: (19)
fliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfectionfliprayzin240sx is close to perfection
Feedback Score: 19 reviews
Send a message via AIM to fliprayzin240sx
Make a boost leak tester...



You can add small gauge on it too so you can see how much pressure you're pumping in there if you're not using a regulated air compressor. Also, you can use a wheel valve stem for the nipple. Lastly spray all your couplers with simple green and it should bubble up if you have a leak.
__________________

If you think Zilvia has too many assholes...
CLICK HERE!!!
fliprayzin240sx is offline   Reply With Quote
Old 08-08-2013, 03:01 AM   #9
Croustibat
Nissanaholic!
 
Join Date: Aug 2011
Location: France - Toulouse
Age: 41
Posts: 1,851
Trader Rating: (0)
Croustibat is an unknown quantity at this point
Feedback Score: 0 reviews
BOVs always leak with a lot of vacuum, typically at idle, unless they have a well made double piston system. It typically produce a 2 to 4 points AFR dip.

Mind you, 4-5 points means quite a serious leak. If that leak was happening all the time, the car would be having trouble and bogging down. If it only happens at idle though, there are great chances it is the BOV.

If you dont have a leak tester, you cant test, simple as that. You can try to loosen every clamps, nudge the couplers then retighten them. It usually works.
Croustibat is offline   Reply With Quote
Old 08-08-2013, 04:26 AM   #10
PureRush
Zilvia Addict
 
Join Date: Oct 2011
Location: Orange County
Posts: 893
Trader Rating: (15)
PureRush is an unknown quantity at this point
Feedback Score: 15 reviews
Could be the fuel pressure regulator. Either the vacuum line or the fpr itself
PureRush is offline   Reply With Quote
Old 08-08-2013, 11:11 AM   #11
shayandude
Zilvia FREAK!
 
Join Date: Feb 2013
Location: louisiana
Posts: 1,184
Trader Rating: (20)
shayandude is an unknown quantity at this point
Feedback Score: 20 reviews
The fuel pressure regular was. Changed by Tay in Dallas along with few other. Things couple months ago. The bov looks like it was on tight and disint hear anything abnormal when revving it. Dealers do vacum leak tests? I wouldn't know where to go for that
shayandude is offline   Reply With Quote
Old 08-09-2013, 08:24 PM   #12
Danger_Dorn
Zilvia Member
 
Danger_Dorn's Avatar
 
Join Date: Oct 2012
Location: Jacksonville NC
Age: 30
Posts: 265
Trader Rating: (0)
Danger_Dorn is an unknown quantity at this point
Feedback Score: 0 reviews
It could be a vacuum leak or it could be the MAF. 99% of the time with the AFR's its that damn maf. check it with a good one and do some vac hunting.
Danger_Dorn is offline   Reply With Quote
Old 08-10-2013, 10:29 AM   #13
shayandude
Zilvia FREAK!
 
Join Date: Feb 2013
Location: louisiana
Posts: 1,184
Trader Rating: (20)
shayandude is an unknown quantity at this point
Feedback Score: 20 reviews
so i figured,the cheapest thing i can start with is the plugs, sicne they are 10 bucks for all 4.
I use the bkr7e btw at .030 at 12 pounds t25
well i drove the car today from hoem to work about 20 min drive, and driving it was between 14.5-16.0 and wot at 10
idle when i got to works parking lot was 13.6-13.8 so im really really hoping it was the plugs, even though they were about 500 miles old.
ill keep everyone posted, planning on driving it a little more today after i get off.
shayandude is offline   Reply With Quote
Old 08-10-2013, 11:11 AM   #14
ultimateirving
Zilvia FREAK!
 
ultimateirving's Avatar
 
Join Date: Nov 2010
Location: arizona
Age: 33
Posts: 1,519
Trader Rating: (1)
ultimateirving is an unknown quantity at this point
Feedback Score: 1 reviews
Quote:
Originally Posted by shayandude View Post
so i figured,the cheapest thing i can start with is the plugs, sicne they are 10 bucks for all 4.
I use the bkr7e btw at .030 at 12 pounds t25
well i drove the car today from hoem to work about 20 min drive, and driving it was between 14.5-16.0 and wot at 10
idle when i got to works parking lot was 13.6-13.8 so im really really hoping it was the plugs, even though they were about 500 miles old.
ill keep everyone posted, planning on driving it a little more today after i get off.
Did you use injector cleaner or similar on the other plugs before the afrs crapped out?
__________________
Z32 with lq4 swap
Desert Street Scene || Dssevents.com
ultimateirving is offline   Reply With Quote
Old 08-10-2013, 12:30 PM   #15
Danger_Dorn
Zilvia Member
 
Danger_Dorn's Avatar
 
Join Date: Oct 2012
Location: Jacksonville NC
Age: 30
Posts: 265
Trader Rating: (0)
Danger_Dorn is an unknown quantity at this point
Feedback Score: 0 reviews
The plugs very rarely have much to do with running rich. If your running rich you will black your plugs very soon so you need to address your fueling issue. I would seriously look at your MAF. The maf I just replaced would sometimes run ok and other times like complete crap. Just swap it out and see if you can pinpoint the problem.

Maybe give this a try? Idk anyone that has but it looks promising Air Flow Meter : Zen Cart!, The Art of E-commerce
Danger_Dorn is offline   Reply With Quote
Old 08-10-2013, 09:41 PM   #16
shayandude
Zilvia FREAK!
 
Join Date: Feb 2013
Location: louisiana
Posts: 1,184
Trader Rating: (20)
shayandude is an unknown quantity at this point
Feedback Score: 20 reviews
Didn't mess with plugs or apply anything to them.
I just Biut a used tested maf from a member recently
shayandude is offline   Reply With Quote
Reply

Bookmarks


Thread Tools
Display Modes

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

Forum Jump


All times are GMT -6. The time now is 04:42 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
vB.Sponsors
Copyright © 1998 - 2019, Zilvia.net™