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 08-23-2014, 08:39 PM   #1
Thomas0zero
Leaky Injector
 
Thomas0zero's Avatar
 
Join Date: Nov 2012
Location: Pryor, Ok
Posts: 65
Trader Rating: (0)
Thomas0zero is an unknown quantity at this point
Feedback Score: 0 reviews
SR20DET, AFR's not changing while in boost.

99% Stock Redtop SR20DET in an S13.

I was running STUPID rich, 10 at idle and cruise, maybe lean out to 11.4 in full boost at redline. Replaced the bad maf pigtail, cleaned maf and fixed the terrible leak between the turbo and manifold. Now the car ran 13.7-15 afr's idle, cruising and in full boost. It has since leaned out and holding 15.7, in and out of boost. Car runs amazing and feels strong, but these lean AFR's are no good.

I dont think it is a clogged fuel filter because the AFR's good at redline before i changed anything.

Things to know.

Boost leak test/vacuum leak. System held 14psi without problems and without any real leaks.
ECU Code 55, all good.
Vacuum lines consist of, FPR, BOV, Gauge, Wastegate and vacuum booster.
Stock boost, Greddy BOV, AEM Wideband, stock injectors, FMIC.

Ive searched quite a bit with no definitive answer. I honestly cant figure out whats going on at this point. I really appreciate your help guys
Thomas0zero is offline   Reply With Quote
Sponsored Links
Old 08-24-2014, 08:16 PM   #2
Thomas0zero
Leaky Injector
 
Thomas0zero's Avatar
 
Join Date: Nov 2012
Location: Pryor, Ok
Posts: 65
Trader Rating: (0)
Thomas0zero is an unknown quantity at this point
Feedback Score: 0 reviews
No one?
Thomas0zero is offline   Reply With Quote
Old 08-25-2014, 07:40 PM   #3
Kingtal0n
Post Whore!
 
Kingtal0n's Avatar
 
Join Date: Jul 2005
Location: South Florida
Age: 38
Posts: 4,648
Trader Rating: (17)
Kingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond repute
Feedback Score: 17 reviews
Send a message via AIM to Kingtal0n
It got lean when you messed with the maf.

Mafs are cheap, go grab several KA24E mafs from anywhere and try them, one at a time, until you find one that gives the a/f you like.

Took me 3 tries to get mine. Some go stupid rich. Some stay lean. They are old...
Its easier to diagnose a lean issue than rich. Lean is very straightforward: you need more gas, which is directly driven by the maf at those pressure ratios.
and worst case scenario, you play with the fuel system (fuel pressure / pump / filter)
__________________
5.3/4l80e/turbo 240sx playthrough:
https://tinyurl.com/turbo240
Kingtal0n is offline   Reply With Quote
Old 08-25-2014, 08:01 PM   #4
Thomas0zero
Leaky Injector
 
Thomas0zero's Avatar
 
Join Date: Nov 2012
Location: Pryor, Ok
Posts: 65
Trader Rating: (0)
Thomas0zero is an unknown quantity at this point
Feedback Score: 0 reviews
Quote:
Originally Posted by Kingtal0n View Post
It got lean when you messed with the maf.

Mafs are cheap, go grab several KA24E mafs from anywhere and try them, one at a time, until you find one that gives the a/f you like.

Took me 3 tries to get mine. Some go stupid rich. Some stay lean. They are old...
Its easier to diagnose a lean issue than rich. Lean is very straightforward: you need more gas, which is directly driven by the maf at those pressure ratios.
and worst case scenario, you play with the fuel system (fuel pressure / pump / filter)
Ill give it a try and let you know what happens. Thanks
Thomas0zero is offline   Reply With Quote
Old 08-26-2014, 01:12 PM   #5
Kingtal0n
Post Whore!
 
Kingtal0n's Avatar
 
Join Date: Jul 2005
Location: South Florida
Age: 38
Posts: 4,648
Trader Rating: (17)
Kingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond reputeKingtal0n has a reputation beyond repute
Feedback Score: 17 reviews
Send a message via AIM to Kingtal0n
it could also be an enormous vacuum leak before the turbo (after the maf)
Kingtal0n is offline   Reply With Quote
Old 08-26-2014, 02:57 PM   #6
Thomas0zero
Leaky Injector
 
Thomas0zero's Avatar
 
Join Date: Nov 2012
Location: Pryor, Ok
Posts: 65
Trader Rating: (0)
Thomas0zero is an unknown quantity at this point
Feedback Score: 0 reviews
No leak before the turbo. We are running hard piping.
Thomas0zero 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 10:38 AM.


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