different readings?lc1 gauge and dataloging - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


MSPNP MSPNP specific Megasquirt related discussion.

Reply
 
 
 
LinkBack Thread Tools
Old 08-25-2011, 02:09 PM   #1
Junior Member
Thread Starter
iTrader: (15)
 
Join Date: Apr 2010
Location: quebec,canada
Posts: 403
Total Cats: 1
Default different readings?lc1 gauge and dataloging

i was street tuning my car the other day, and got it to run 11.1-11.3 [email protected]
i did a datalog and it says that i never even toutched 11' on the whole run.more like 10.6-10.8.

my lc1 gauge is wired to the same wire that goes to my MS on the center plug.

if both are on the same wire, how can i have different reading?i did perform a free air calibration before tuning it. on iddle, cruise and normal driving both are the same,wich seems to be weird.

thanks for your time
kaboshe is offline   Reply With Quote
Old 08-25-2011, 02:11 PM   #2
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

voltage offset.
Braineack is offline   Reply With Quote
Old 08-25-2011, 02:12 PM   #3
Junior Member
Thread Starter
iTrader: (15)
 
Join Date: Apr 2010
Location: quebec,canada
Posts: 403
Total Cats: 1
Default

and for the frensh-speaking that knows next to nothing to voltage,could you explain?

both the gauge and the ms wouldn't have the same reading because i ''splitted'' the signal?
kaboshe is offline   Reply With Quote
Old 08-25-2011, 02:14 PM   #4
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

it's the ground wire that's the problem.
Braineack is offline   Reply With Quote
Old 08-25-2011, 02:19 PM   #5
Junior Member
Thread Starter
iTrader: (15)
 
Join Date: Apr 2010
Location: quebec,canada
Posts: 403
Total Cats: 1
Default

ground goes straight from the lc1 module and bolts right up on the valvecover. i also got a suplementary ground on the same bolt going to the firewall

where did i went wrong?
kaboshe is offline   Reply With Quote
Old 08-25-2011, 02:29 PM   #6
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

does the megasquirt ground at the valve cover and/or firewall?
Braineack is offline   Reply With Quote
Old 08-25-2011, 02:37 PM   #7
Junior Member
Thread Starter
iTrader: (15)
 
Join Date: Apr 2010
Location: quebec,canada
Posts: 403
Total Cats: 1
Default

since it's a PNP, it use the oem grounds. i couldn't say wich one it is ,but i kept all of em.

having 2-3 ground on the same bolt could cause that kind of problem?


thanks a million for the info
kaboshe is offline   Reply With Quote
Old 08-25-2011, 03:34 PM   #8
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

have the grounds on different bolts is the problem.
Braineack is offline   Reply With Quote
Old 09-17-2011, 01:20 PM   #9
Junior Member
iTrader: (2)
 
Join Date: May 2009
Posts: 68
Total Cats: 0
Default

wow, having the 2 ground in the same place but on different bolts will cause a voltage offset...WHO WOULD HAVE EVER GUESSED THAT!
Weaver is offline   Reply With Quote
Old 09-17-2011, 08:37 PM   #10
Junior Member
Thread Starter
iTrader: (15)
 
Join Date: Apr 2010
Location: quebec,canada
Posts: 403
Total Cats: 1
Default

they are all on the same bolt, on the VC.why this kind of post weaver
kaboshe is offline   Reply With Quote
Old 09-18-2011, 04:57 PM   #11
Junior Member
iTrader: (2)
 
Join Date: May 2009
Posts: 68
Total Cats: 0
Default

why not?
Weaver is offline   Reply With Quote
Old 09-18-2011, 06:06 PM   #12
Elite Member
iTrader: (2)
 
triple88a's Avatar
 
Join Date: Apr 2006
Location: Chicago, IL
Posts: 9,131
Total Cats: 598
Default

I've noticed that on my adaptronic also. Gauge says 14 or something, adaptronic says 13.5. (serial to adaptronic, 1 wire to gauge, both gauge and the lc1 are connected to the same + and ground source).
triple88a is offline   Reply With Quote
Old 09-18-2011, 06:13 PM   #13
Tour de Franzia
iTrader: (6)
 
hustler's Avatar
 
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,114
Total Cats: 351
Default

Electrons, are they positive or negative? Wait, batteries don't store electrons?
hustler is offline   Reply With Quote
Old 09-18-2011, 07:18 PM   #14
Junior Member
iTrader: (4)
 
Join Date: May 2009
Location: Novi, MI
Posts: 308
Total Cats: 1
Default

I've got the same issue and mine is wired into the stock ground. It's 0.7-0.8 off.
Larimer is offline   Reply With Quote
Old 09-18-2011, 08:31 PM   #15
Tour de Franzia
iTrader: (6)
 
hustler's Avatar
 
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,114
Total Cats: 351
Default

Quote:
Originally Posted by Larimer View Post
I've got the same issue and mine is wired into the stock ground. It's 0.7-0.8 off.
Try mixing E85 and gasoline in the tank until the AFR numbers match.
hustler is offline   Reply With Quote
Old 09-18-2011, 08:46 PM   #16
Junior Member
iTrader: (4)
 
Join Date: May 2009
Location: Novi, MI
Posts: 308
Total Cats: 1
Default

Quote:
Originally Posted by hustler View Post
Try mixing E85 and gasoline in the tank until the AFR numbers match.


Not sure which to trust now either.
Larimer is offline   Reply With Quote
Old 09-18-2011, 09:09 PM   #17
Elite Member
iTrader: (2)
 
triple88a's Avatar
 
Join Date: Apr 2006
Location: Chicago, IL
Posts: 9,131
Total Cats: 598
Default

Quote:
Originally Posted by hustler View Post
Try mixing E85 and gasoline in the tank until the AFR numbers match.

Hustler, i'll bring out the crazy white wig and the test tubes at the gas station while i'm at it LIKE A BOSS


When the employee comes out of the **** box and asks what am i doing i'll tell him i'm going back to the future.
triple88a is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 59 Yesterday 09:00 PM
OTS Bilstein to motorsports ASN conversion stoves Suspension, Brakes, Drivetrain 5 04-21-2016 04:00 PM
My solution for Oiltemp and Oilpressure input into Megasuirt (MS3) Zaphod MEGAsquirt 41 01-24-2016 01:25 PM
Time to start learning and play with tuning The Gleas MEGAsquirt 3 10-01-2015 10:30 AM


Thread Tools

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 09:15 AM.