Any way to run a Flat Top manifold on NB2 and pass smog? - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 11-17-2015, 11:57 PM   #1
Junior Member
Thread Starter
iTrader: (5)
 
Join Date: Oct 2011
Location: San Diego, CA
Posts: 402
Total Cats: 21
Default Any way to run a Flat Top manifold on NB2 and pass smog?

I've got a Flat Top that I'd like to install soon and have to smog the car this month. After I put in my stock injectors and ECU back in, I decided to see if it's possible to not run VTCS and not get a CEL, before I put the Flat Top on.

Glad I decided to wait on the manifold because pretty much everything I've done hasn't worked and from reading around a little, it doesn't seem like anyone has ever done this. Which amazes me.

You can not just leave the solenoid connected to the loom. It still throws a CEL. This might work for VICS, but not VTCS. Anyone else got any ideas?

Thanks.
slmhofy is offline   Reply With Quote
Old 11-18-2015, 12:01 AM   #2
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,199
Total Cats: 2,584
Default

why can't you just leave it plugged in but cap it? there's no position sensor on the actuator or flaps, how does the car tell it's not working? by measuring airflow on cold start?

I haven't done that, but always thought it would be possible/easy
18psi is offline   Reply With Quote
Old 11-18-2015, 11:20 AM   #3
Junior Member
Thread Starter
iTrader: (5)
 
Join Date: Oct 2011
Location: San Diego, CA
Posts: 402
Total Cats: 21
Default

I tried leaving the solenoid plugged in to the loom and capped off all the vacuum ports on the manifold and it still sets a CEL I think after 2 consecutive times of seeing whatever it sees. I could try capping off both of the ports on the solenoid, but I'm not sure how that would be any different from them being open on both sides.

And I'm not sure how to knows, I'd assume by measuring air flow at during warm up. I've still got my wide band if you try driving it right away when it's pretty cold like it's been the last few days, it will get some pretty bad lean tip in. IE 16-7:1 afr.
slmhofy is offline   Reply With Quote
Old 11-18-2015, 11:51 AM   #4
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,199
Total Cats: 2,584
Default

Put a restrictor into the intake path?
Like a piece of cardboard into the airbox so you can take it out in 5 seconds after the car warms up, do that a couple times and should be ready for smog
18psi is offline   Reply With Quote
Old 11-19-2015, 04:02 PM   #5
Boosting since 1984
iTrader: (1)
 
stefanst's Avatar
 
Join Date: Sep 2011
Location: Levittown
Posts: 1,198
Total Cats: 68
Default

Replace NB2 ECU with NB1 ECU.

I have one for sale :-)
stefanst is offline   Reply With Quote
Old 11-19-2015, 04:42 PM   #6
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Delicious and Moist.
Posts: 26,327
Total Cats: 1,926
Default

Quote:
Originally Posted by 18psi View Post
there's no position sensor on the actuator or flaps, how does the car tell it's not working?
There is a vacuum switch teed into the vacuum line between the VTCS solenoid and the actuator. The ECU wants to see verification from that switch that vacuum is present / absent depending upon the commanded position of the solenoid.

So you need to leave the solenoid connected to both electricity and vacuum, and also leave the vacuum switch connected to the solenoid.

This is from a 2002 non-MSM manual, but it should be close:


Attached Thumbnails
Any way to run a Flat Top manifold on NB2 and pass smog?-80-vtcs_switch_8a9e4f12fc72935e91178dd2941be25e539bb9e4.gif  
Joe Perez is offline   Reply With Quote
Old 11-19-2015, 04:43 PM   #7
mkturbo.com
iTrader: (24)
 
shuiend's Avatar
 
Join Date: May 2006
Location: Charleston SC
Posts: 13,780
Total Cats: 1,106
Default

Quote:
Originally Posted by stefanst View Post
Replace NB2 ECU with NB1 ECU.

I have one for sale :-)
Wiring and plugs are completely different.
shuiend is offline   Reply With Quote
Old 11-19-2015, 04:46 PM   #8
Boosting since 1984
iTrader: (1)
 
stefanst's Avatar
 
Join Date: Sep 2011
Location: Levittown
Posts: 1,198
Total Cats: 68
Default

Quote:
Originally Posted by shuiend View Post
Wiring and plugs are completely different.
I didn't say it would be easy!
stefanst is offline   Reply With Quote
Old 11-19-2015, 04:58 PM   #9
I take big bites
iTrader: (1)
 
turbofan's Avatar
 
Join Date: Sep 2010
Location: Hurricane, UT
Posts: 6,927
Total Cats: 526
Default

Now I need that neg prop button.
turbofan is offline   Reply With Quote
Old 11-19-2015, 05:14 PM   #10
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,199
Total Cats: 2,584
Default

Quote:
Originally Posted by Joe Perez View Post
There is a vacuum switch teed into the vacuum line between the VTCS solenoid and the actuator. The ECU wants to see verification from that switch that vacuum is present / absent depending upon the commanded position of the solenoid.

So you need to leave the solenoid connected to both electricity and vacuum, and also leave the vacuum switch connected to the solenoid.

This is from a 2002 non-MSM manual, but it should be close:


so basically, re-install the vtcs actuator and just have opening/closing nothing
18psi is offline   Reply With Quote
Old 11-19-2015, 05:19 PM   #11
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Delicious and Moist.
Posts: 26,327
Total Cats: 1,926
Default

Quote:
Originally Posted by 18psi View Post
so basically, re-install the vtcs actuator and just have opening/closing nothing
You don't even need the actuator, just connect a vacuum hose directly between the solenoid and the sensor.
Joe Perez is offline   Reply With Quote
Old 11-21-2015, 04:36 PM   #12
Junior Member
Thread Starter
iTrader: (5)
 
Join Date: Oct 2011
Location: San Diego, CA
Posts: 402
Total Cats: 21
Default

Thank you everyone for your help. Here is the actual CEL that is thrown.

So if you want to run a Flat Top and pass CA SMOG with an NB2, you need to keep the solenoid plugged in electrically and with the two vacuum hoses. One to the manifold and the other the the VTCS vacuum switch by the passenger shock tower.

PSA: There's no where to mount the solenoid on the Flat Top so you're gonna have **** hanging around if you don't make something for it.


Attached Thumbnails
Any way to run a Flat Top manifold on NB2 and pass smog?-80-screenshot_2015_11_16_11_46_26_a6ad71913dad8c9b1d11ca7de0bfe07f63fdd811.png   Any way to run a Flat Top manifold on NB2 and pass smog?-80-screenshot_2015_11_16_11_46_26b_c1fae01edbb58290eecad59d7f80fbf5a8d55fb7.png  
slmhofy is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
manifold comparison Guy Farting Prefabbed Turbo Kits 24 01-05-2016 03:20 PM
Adaptronic Select PNP ECU eSel039 hankclaussen Miata parts for sale/trade 2 11-30-2015 02:06 PM
Part Out Sale! 1.6 BEGi S2 GT2560R kit, injectors, MSPNP, full 3" exhaust and more. Trent Miata parts for sale/trade 12 11-25-2015 07:47 PM
Hard top mounts, 03 seatbelts, 91 throttle body Markus Miata parts for sale/trade 3 11-12-2015 08:31 PM
TRADE: BLACK Hard top for WHITE demoniam Miata parts for sale/trade 0 11-12-2015 12:59 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 12:11 PM.