Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster Racing Forum

Post Reply
 
LinkBack Thread Tools Display Modes
Old 07-17-2017, 11:10 AM   #1
Registered User
 
seningen's Avatar
 
Join Date: Jul 2008
Location: austin
Posts: 823
Do 97-99's have OBDII wires for sensors?

I was wondering if in the SPBs we can pick off Oil Pressure, Oil Temp, Water Temp, Tranny Temp off the OBDII?

Let me clarify -- what I am after is physically splicing a wire and routing that to my Traqmate as a digital or analog input.

I'd prefer to send the to my Traqmate data logger and TD rather than add a bunch of gauges and new senders (unless I have to)

thanks,

Mike

__________________
Drivers: '15 Panamera Hybrid (wife's), ' 01 996 GT2, 00 Boxster S, '96 993 Çab/Tip (wife's)
Race Cars: '75 911 RSR Replica & '99 Spec Boxster
mike@lonestarrpm.com
seningen is offline   Reply With Quote
Old 07-17-2017, 12:03 PM   #2
Registered User
 
Join Date: Feb 2005
Location: It's a kind of magic.....
Posts: 6,261
Mike, the OBDII system in these cars reads off the DME, not the sensors directly. The sensor are sending fractional or low voltage signals to the DME, which converts them into what are referred to as "PID's", which are the reading values. Tapping into the sensor wiring will only give you the voltage. You can read a significant number of the PID values directly off the OBDII port however.
__________________
Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein
JFP in PA is online now   Reply With Quote
Old 07-18-2017, 06:18 AM   #3
Registered User
 
Join Date: Dec 2011
Location: SLC
Posts: 209
If your Traqmate logger can read K-line your all set and should be able to get Water temp, Throttle position, etc.

Most loggers use CAN for data from the ECU. Unfortunately Porsche was a bit behind other marques in getting that protocol to their ECUs and didn't really get it together until around 2006.

K-line unfortunately has very slow sampling frequencies (<10Hz) so there is some delay in sensor readings.

For Oil pressure you need to install a sensor since the 986 doesn't have one.
MaxD is offline   Reply With Quote
Old 07-18-2017, 07:11 AM   #4
Registered User
 
Lemming's Avatar
 
Join Date: Apr 2016
Location: B'ham, AL
Posts: 266
Are you sure of that? How dies the low oil pressure light function without that type of information?

EDIT: The wiring diagram shows an oil pressure switch, with a GN/WT wire that feeds directly into the White plug (position 6) in the instrument cluster. Not sure if this is an on/off voltage or if voltage is related to oil pressure in a linear fashion that could be used with traqmate. It would be easy enough to put a meter to it and rev the engine to see if there is a voltage increase with increased oil pressure.
__________________
Tim
1998 986 (daily driver Frankencar)
1999 986 (SPB)
2001 986 S (parting)
2015 981 (sold)

Last edited by Lemming; 07-18-2017 at 07:51 AM.
Lemming is offline   Reply With Quote
Old 07-18-2017, 07:45 AM   #5
Registered User
 
Join Date: Feb 2005
Location: It's a kind of magic.....
Posts: 6,261
Quote:
Originally Posted by Lemming View Post
Are you sure of that? How dies the low oil pressure light function without that type of information?

EDIT: The wiring diagram shows an oil pressure switch, with a GN/WT wire that feeds directly into the White plug (position 6) in the instrument cluster. Not sure if this is an on/off voltage or if voltage is related to oil pressure in a linear fashion that could be used with traqmate. It would be easy enough to put a meter to it and rev the engine to see if there is a voltage increase with increased oil pressure.
This engine uses and pressure switch preset around 5PSIG to trigger the dash light. to get pressure readings, you need to replace it with a variable sender.
__________________
Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein
JFP in PA is online now   Reply With Quote
Old 07-18-2017, 07:53 AM   #6
Registered User
 
Lemming's Avatar
 
Join Date: Apr 2016
Location: B'ham, AL
Posts: 266
Yes, I replaced the existing sensor with a VDO and just tapped into the wire in the cluster as I was not sure of the stock sensor output.
__________________
Tim
1998 986 (daily driver Frankencar)
1999 986 (SPB)
2001 986 S (parting)
2015 981 (sold)
Lemming is offline   Reply With Quote
Old 07-18-2017, 01:41 PM   #7
Registered User
 
Join Date: Dec 2011
Location: SLC
Posts: 209
The 911 had a dual temp and pressure sensor for the 99 model year. Probably the only reason one would put a 996 dash in a SPB (it's legal) if you don't have data acquisition.

Generally it is best to have another set of sensors for your logger if you don't have CAN from the ECU. I know it ends up being more $$$, but the lack of gremlins from splitting signals/wires is worth it in the long run.

I use AIM, have an MXL in the Boxster and an MXL2 in the M3. The Boxster has it's own set of engine sensors for the MXL + Steering angle + Brake pressure. I use the BMW version of CAN for the M3 which while it offers quite a few channels it still doesn't have oil temp or pressure. Separate sensors required for those channels.

MaxD is offline   Reply With Quote
Post Reply


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 On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 07:51 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page