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

Tech Talk Technical Discussion About The Nissan 240SX and Nissan Z Cars


Reply
 
Thread Tools Display Modes
Old 12-03-2019, 08:47 PM   #1
oLemurs
Zilvia Member
 
oLemurs's Avatar
 
Join Date: Aug 2017
Location: MO
Posts: 197
Trader Rating: (0)
oLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura about
Feedback Score: 0 reviews
backfire and breaking up issues

Hello everyone, my sr20det s13 has been having issues when it gets into boost it will backfire very bad. this only happens when the engine is very warm and it seems like it gets worse the warmer it gets. when the engine is cold i can get a good 3-4 WOT pulls before it starts to break up and when it does break up usually it backfires alot and stops accelerating pretty much completely. this issue only started happening after i swapped in my s15 turbo, here is what ive looked over. new copper plugs, tried .22 .25 .28 gap and no change. R8 coil packs upgrade. the only other new parts on this is my used HKS adjustable wastegate. any help is appreciated and before you start YES i did use search but its been months that my cars been down and i cant seem to figure out this shitty issue. also it throws no codes for anything.

also boosts to around 13 psi and holds it until it starts to break up
oLemurs is offline   Reply With Quote
Sponsored Links
Old 12-03-2019, 10:47 PM   #2
Silv1401
Zilvia Member
 
Silv1401's Avatar
 
Join Date: Jan 2019
Location: Vancouver, WA/Portland, OR, USA
Posts: 166
Trader Rating: (1)
Silv1401 is an unknown quantity at this point
Feedback Score: 1 reviews
What heat rating are the plugs you're using? I had the same issue when I got my KA-T S14. WOT would cause a lot of bogging and black smoke, max psi was usually about 4psi, out of a tune meant for 16psi. Originally my wastegate flange was warped, and the gasket was blown (2-point flanges are dumb, btw) and I fixed it, which managed to get me a couple more PSI of boost. Then changed my plugs, and went up a heat rating from 6 to 7s. Instant fix. So, check your wastegate for proper plumbing, and seal around the exhaust side. Then try upping your plug heat range if that doesn't work.

Sent from my SM-G950U using Tapatalk
Silv1401 is offline   Reply With Quote
Old 12-04-2019, 09:19 AM   #3
jedi03
Nissanaholic!
 
Join Date: Jul 2008
Location: albuquerque
Posts: 1,786
Trader Rating: (8)
jedi03 is on a distinguished road
Feedback Score: 8 reviews
agreed sounds like blowing out the spark...close the gap as opposed to opening it and check what your actual boost is, had buddy who was unknowingly overboosting his tune by ~15psi (evo) and kept wondering what was going on, got a good boost guage and turned down the boost then all was good!
jedi03 is offline   Reply With Quote
Old 12-04-2019, 10:51 AM   #4
oLemurs
Zilvia Member
 
oLemurs's Avatar
 
Join Date: Aug 2017
Location: MO
Posts: 197
Trader Rating: (0)
oLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura about
Feedback Score: 0 reviews
Quote:
Originally Posted by jedi03 View Post
agreed sounds like blowing out the spark...close the gap as opposed to opening it and check what your actual boost is, had buddy who was unknowingly overboosting his tune by ~15psi (evo) and kept wondering what was going on, got a good boost guage and turned down the boost then all was good!
i will just try turning down the boost most of the way, will check in later thanks for the help
oLemurs is offline   Reply With Quote
Old 12-04-2019, 10:52 AM   #5
brndck
Premium Member
 
brndck's Avatar
 
Join Date: Jun 2003
Location: torrance, ca
Age: 39
Posts: 12,407
Trader Rating: (129)
brndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfection
Feedback Score: 129 reviews
Send a message via AIM to brndck
+1 for check your boost level.
sounds like you need to check quite a number of things before we can help you pinpoint the issue

FAST

Fuel
Air
Spark
Timing
__________________

http://outslidersandsmokeproduce.blogspot.com/
Quote:
Originally Posted by Mannykiller View Post
it'll fit JANK.. and no one likes Jank except Broke ass zilvians.
brndck is offline   Reply With Quote
Old 12-04-2019, 02:40 PM   #6
jdmgtom
Leaky Injector
 
jdmgtom's Avatar
 
Join Date: Aug 2018
Location: St. Petersburg, FL
Age: 28
Posts: 147
Trader Rating: (0)
jdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymore
Feedback Score: 0 reviews
I had similar issues with my s13 sr20det running worse when temps were up. My tuner told me it was due to my stock injectors. I upgraded to 550cc DW injectors and z32 MAF and running a s15 turbo as well and got a rom tune. The new injectors or the new MAF seemed to fix the issue but then again my car is still not 100%. I also bought a brand new HKS actuator and a Apexi 1.1mm headgasket with ARP head studs. So I haven't driven the car long enough with the new setup to see if it really fixed anything.
__________________
_________
IG - g_t0m
jdmgtom is offline   Reply With Quote
Old 12-04-2019, 02:52 PM   #7
brndck
Premium Member
 
brndck's Avatar
 
Join Date: Jun 2003
Location: torrance, ca
Age: 39
Posts: 12,407
Trader Rating: (129)
brndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfection
Feedback Score: 129 reviews
Send a message via AIM to brndck
Quote:
Originally Posted by jdmgtom View Post
I had similar issues with my s13 sr20det running worse when temps were up. My tuner told me it was due to my stock injectors.
uhhhhhh that sounds like BS.

did you have a upgraded turbo or were you running more boost than the injectors could supply fuel for?
__________________

http://outslidersandsmokeproduce.blogspot.com/
Quote:
Originally Posted by Mannykiller View Post
it'll fit JANK.. and no one likes Jank except Broke ass zilvians.
brndck is offline   Reply With Quote
Old 12-04-2019, 03:04 PM   #8
jdmgtom
Leaky Injector
 
jdmgtom's Avatar
 
Join Date: Aug 2018
Location: St. Petersburg, FL
Age: 28
Posts: 147
Trader Rating: (0)
jdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymorejdmgtom is not welcome here anymore
Feedback Score: 0 reviews
Quote:
Originally Posted by brndck View Post
uhhhhhh that sounds like BS.

did you have a upgraded turbo or were you running more boost than the injectors could supply fuel for?
At the time, I was only running a s15 turbo and everything else was stock, with basic bolt on's running stock boost but even when I had the stock s13 t25 turbo, it was doing the same thing but a lot worse. That was the main reason I upgraded to a s15 turbo because I was convinced that the t25 was the cause. I will say that I f'd up and made a noob mistake with my s15 turbo, I turned the rod and probably messed up the diaphragm on the stock actuator thinking it was adjustable, that's the reason why I bought a new HKS actuator.
__________________
_________
IG - g_t0m
jdmgtom is offline   Reply With Quote
Old 12-04-2019, 03:12 PM   #9
brndck
Premium Member
 
brndck's Avatar
 
Join Date: Jun 2003
Location: torrance, ca
Age: 39
Posts: 12,407
Trader Rating: (129)
brndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfectionbrndck is close to perfection
Feedback Score: 129 reviews
Send a message via AIM to brndck
Quote:
Originally Posted by jdmgtom View Post
At the time, I was only running a s15 turbo and everything else was stock, with basic bolt on's running stock boost but even when I had the stock s13 t25 turbo, it was doing the same thing but a lot worse. That was the main reason I upgraded to a s15 turbo because I was convinced that the t25 was the cause. I will say that I f'd up and made a noob mistake with my s15 turbo, I turned the rod and probably messed up the diaphragm on the stock actuator thinking it was adjustable, that's the reason why I bought a new HKS actuator.
boost gauge. you need a boost gauge. if you don't even know what you're pushing, you can't start diagnosing shit. install the new hks actuator, set it to 7psi, then start troubleshooting.
__________________

http://outslidersandsmokeproduce.blogspot.com/
Quote:
Originally Posted by Mannykiller View Post
it'll fit JANK.. and no one likes Jank except Broke ass zilvians.
brndck is offline   Reply With Quote
Old 12-06-2019, 01:26 PM   #10
Shouldabeen11b
 
Join Date: Dec 2019
Location: Georgia
Age: 26
Posts: 2
Trader Rating: (0)
Shouldabeen11b is an unknown quantity at this point
Feedback Score: 0 reviews
Yeah I’m having the same issue with my car. S13 sr20 with a 3871r rom tune and z32 maf everything brand new out of box. Also a 255 warlboro. The first few pulls I can pull all the way to redline, but after that I will hit a brick wall of a twostep sounding breaking up, and I have to shutoff the car and turn it back on for it to stop. I’ve been fighting it for two months so if anyone has any ideas please help. I’m tuned at 12 lbs but only running seven Bc I have an internal wastegate and I’m scared to splice into the vaccum line on the turbo that came with it.

Edit: also running 750cc. Injectors and all the o rings are good
Shouldabeen11b is offline   Reply With Quote
Old 12-06-2019, 01:37 PM   #11
oLemurs
Zilvia Member
 
oLemurs's Avatar
 
Join Date: Aug 2017
Location: MO
Posts: 197
Trader Rating: (0)
oLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura about
Feedback Score: 0 reviews
Quote:
Originally Posted by Shouldabeen11b View Post
Yeah I’m having the same issue with my car. S13 sr20 with a 3871r rom tune and z32 maf everything brand new out of box. Also a 255 warlboro. The first few pulls I can pull all the way to redline, but after that I will hit a brick wall of a twostep sounding breaking up, and I have to shutoff the car and turn it back on for it to stop. I’ve been fighting it for two months so if anyone has any ideas please help. I’m tuned at 12 lbs but only running seven Bc I have an internal wastegate and I’m scared to splice into the vaccum line on the turbo that came with it.

Edit: also running 750cc. Injectors and all the o rings are good
exactly whats happening to me im just on a pretty much stock motor
oLemurs is offline   Reply With Quote
Old 12-06-2019, 02:28 PM   #12
oLemurs
Zilvia Member
 
oLemurs's Avatar
 
Join Date: Aug 2017
Location: MO
Posts: 197
Trader Rating: (0)
oLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura aboutoLemurs has a spectacular aura about
Feedback Score: 0 reviews

Alright got some data logs, here selected is the point of break up. the only thing i notice is the o2 sensor
C=RPM D- water temp E=battery F=throttle G=timing H-AAC I=injector J=o2 K=MAF L=MPG also shouldnt my o2 sensor be fluctuating? its a pretty new one im wondering if i should swap a fresh one in. i still get no codes

Last edited by oLemurs; 12-06-2019 at 03:53 PM..
oLemurs is offline   Reply With Quote
Old 12-09-2019, 10:06 AM   #13
Shouldabeen11b
 
Join Date: Dec 2019
Location: Georgia
Age: 26
Posts: 2
Trader Rating: (0)
Shouldabeen11b is an unknown quantity at this point
Feedback Score: 0 reviews
did you ever figure this out? im still lost.
Shouldabeen11b is offline   Reply With Quote
Old 12-09-2019, 10:45 AM   #14
S14rebuild
BANNED
 
Join Date: May 2019
Location: Florida-FAIL
Posts: 2,497
Trader Rating: (8)
S14rebuild S14rebuild S14rebuild S14rebuild S14rebuild S14rebuild S14rebuild S14rebuild S14rebuild S14rebuild S14rebuild
Feedback Score: 8 reviews
Tps is reading 3.88v and maf is at 4.54 idk if thats right...seems like the maf is almost maxed out... idk though. And yes the o2 should fluctuate
S14rebuild is offline   Reply With Quote
Old 12-15-2019, 07:17 PM   #15
Kingtal0n
Post Whore!
 
Kingtal0n's Avatar
 
Join Date: Jul 2005
Location: South Florida
Age: 38
Posts: 4,649
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
1. pressure test system to 20psi "boost leak test"
2. collect wideband data somehow, either use video or a data logger with the wideband
3. tune the engine properly
Kingtal0n 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 10:57 PM.


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