Taurus Car Club of America : Ford Taurus Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
47 Posts
Discussion Starter · #1 ·
I have an 02 Taurus with the 3.0L OHV engine. My scan tool reports the fuel system in Closed loop all the time, even when the engine is cold and has just been started. Anyone have any ideas why it would do this?

PS
I am troubleshooting a misfire. The Mode 6 data I retrieve from the scan tool shows misfires on all cylinders but they are not bad enough to set a DTC. It's not the plugs, wires or coil pack as all have been replaced. I've been tracking this for a long time. Thanks.
 

·
Super Moderator
Joined
·
8,623 Posts
Modern engines go into closed loop very quickly, but not instantly. I have noticed the same thing on my limited PID output handheld Actron graphing scanner (9185 or something like that) and never understood it either. I never even checked my PC based bidirectional scan tool (near dealer level functionality) to see what it said at cold startup, since I have never selected that PID for viewing.

Only thing I can think of is when I set up either scan tool, I plug them in the OBDII port, and turn the key to run for setup, PID validation, etc. With key in run, O2 heaters are active, and maybe by the time I get around to starting the engine the O2s have gotten hot enough with the electric heaters alone that it goes closed loop very quickly. This is, of course, a wild off the wall guess.
 

·
Registered
Joined
·
49 Posts
I have an 02 Taurus with the 3.0L OHV engine. My scan tool reports the fuel system in Closed loop all the time, even when the engine is cold and has just been started. Anyone have any ideas why it would do this?

PS
I am troubleshooting a misfire. The Mode 6 data I retrieve from the scan tool shows misfires on all cylinders but they are not bad enough to set a DTC. It's not the plugs, wires or coil pack as all have been replaced. I've been tracking this for a long time. Thanks.
I have been troubleshooting a misfire issue myself for a while now. Here is the Thread:
http://www.taurusclub.com/forum/82-maintenance-repair/160037-idle-throttle-problem-97-3-0-ohv.html

I have done everything imaginable to trace it down. Drove around with the laptop and Ford IDS running a data log and still nothing.
Mine always says "Closed Loop" as well. I have access to all of Fords wonderful diagnostic tools so if you want to PM me and maybe we can share some info if you are having the same issue.
 

·
Premium Member
Joined
·
449 Posts
Have you checked the Coolant temp sensor? Thats one of the ways it knows wether to go into cl or not...
 
1 - 4 of 4 Posts
Top