Nissan 370Z Forum  

AFR problems

Hi there, 2015 Nismo 6MT BP single kit, Motordyne exhaust, open dumps, stock block, ID 1050cc injectors, 340lph pump, s1.e fuel return, remote tuned by Seb @ 12psi. 33,000 miles,

Go Back   Nissan 370Z Forum > Nissan 370Z Tech Area > Engine & Drivetrain > Forced Induction


Like Tree3Likes
  • 3 Post By redondoaveb

Reply
 
LinkBack Thread Tools Display Modes
Old 03-11-2021, 12:00 AM   #1 (permalink)
Base Member
 
Join Date: Nov 2016
Location: Washington State
Posts: 66
Drives: 15 370z 6MT Nismo
Rep Power: 8
Gooch will become famous soon enough
Default AFR problems

Hi there,

2015 Nismo 6MT BP single kit, Motordyne exhaust, open dumps, stock block, ID 1050cc injectors, 340lph pump, s1.e fuel return, remote tuned by Seb @ 12psi. 33,000 miles, about 8000 on the turbo kit. For the first few months, car ran perfectly. Then, overnight, my aftermarket AFR gauge starting reading about 1 unit richer at idle. The weird thing is, the oem sensors still read 14.7. I thought no problem, the oem sensors went bad. I replaced those and the problem remains. Then I thought it was the aftermarket gauge. I replaced all the wires, sensor, gauge, module, and the problem remained. You can definitely smell the extra gas. At WOT, the afr is also richer but is within acceptable values. (10.5-11.5). Another symptom, when cruising, and letting off the gas, about half the time when coming back into the gas, the cruising afr is super rich at about 12:1 for 20-30 seconds before normalizing back to 13.5-13.7.

The car is still lightning fast and if it werent for the afr reading itself, and the smell, you would never know anything is wrong. But I figure it’s time to get to the bottom of this before things get too fouled. If anyone has any ideas before I throw more parts at it I would appreciate it. Thanks
__________________
'15 370z Nismo Tech 6MT Magnetic Black, V2 BP Kit 6467, Motordyne e370, ECUTEK| '06 350z Touring 6MT Carbon Silver
Gooch is offline   Reply With Quote
Old 03-11-2021, 12:32 AM   #2 (permalink)
A True Z Fanatic
 
redondoaveb's Avatar
 
Join Date: Apr 2017
Location: So. Commiefornia
Posts: 6,290
Drives: 2014 Nismo Gunmetal
Rep Power: 2684373
redondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond reputeredondoaveb has a reputation beyond repute
Default

Here's a video Seb posted on Youtube last night showing how you would be getting different readings from your factory sensors than your aftermarket gauge sensor(s). I know it doesn't answer your issue but still good info. Have you emailed Seb, he'll probably want to look at your logs.

https://youtu.be/zf3U7OxlwHY
Hotrodz, Optimiser and Gooch like this.
__________________
Fast Intentions "Stage Seb" twin turbo #098- Specialty Z/Tial-Xonarotor/CJM/Ecutek/HKS/KW/SPL/Hotchkis/Rohana/Toyo
700+whp
redondoaveb is offline   Reply With Quote
Old 03-12-2021, 12:42 AM   #3 (permalink)
Base Member
 
Join Date: Nov 2016
Location: Washington State
Posts: 66
Drives: 15 370z 6MT Nismo
Rep Power: 8
Gooch will become famous soon enough
Default

Neat video. I have spoken to Seb about this problem in the past. I sent him logs and he even adjusted the tune for the WOT richness. Honestly, I think he kind of grew tired of me complaining about the unusual behavior I was experiencing and he attributed it to normal divergences that he displayed in the video you posted. He said it was normal. The reason why I beg to disagree, for my case at least, is because it did not do this when he initially tuned it and for many months and thousands of miles after. Additionally, the AFR divergences are most notable at low loads (idle and cruising) rather than high loads, as you might expect. This is why I began to suspect a mechanical defect. But I can’t think of what defect would cause this. So, perhaps we should just try tuning this condition out? Of course, that should be the last thing we try, hence this thread..

I realize this was kind of a shot in the dark. It is difficult to diagnose problems like these over the internet. But it was worth seeing if someone had experienced something similar.

Thank you for your input!
__________________
'15 370z Nismo Tech 6MT Magnetic Black, V2 BP Kit 6467, Motordyne e370, ECUTEK| '06 350z Touring 6MT Carbon Silver
Gooch 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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
7A problems again! Help?! AstatenateZ Engine & Drivetrain 7 02-06-2020 08:37 AM
6mt problems Chrisc3 Engine & Drivetrain 5 08-03-2019 06:52 PM
Z problems?????? duggie2fresh New 370Z Owner 5 04-12-2016 09:49 AM
top problems tommy_nick Nissan 370Z Roadster (Convertible) 3 01-21-2015 03:56 PM
Problems... Ni55anPat The Lounge (Off Topic) 3 12-10-2011 12:08 PM


All times are GMT -5. The time now is 08:43 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2