What is an output sensor circuit malfunction?

[Rickey_Bobby]

what is an output sensor circuit malfunction?
I had Advance Auto do one of those "free scans" today because my 1999 GT has been stalling when I come to a stop with the clutch in. The idle will wander between 800 and 200rpm then die. But this only happens when the car is moving.


Here are the codes I got: (written exactly as the print out has them)

DTC (codes)

P0125
closed loop fuel control
insufficient
coolant temp

DTC Pending (codes)

P0356
ignition coil F
primary/secondary
circuit malfunction

P0720
output speed sensor
circuit malfunction

The car had a misfire due to water in a plug hole. I have since replaced all coils and the misfire is gone. Also, the car was driven with the thermostat removed for about a month. Both were done before the scan.

If i have a speed sensor problem, how is the speedometer still working?

Also, what is the difference between "DTC" and "DTC pending"

Any ideas?

 

[sgarlic]

1st one is from not having a t-stat. The PCM needs to see a certain temperature coolant before it switches to closed loop. No t-stat usually prevents the coolant from fully heating up.

2nd one is probably from the misfire prob you had, and once you clear it it should be gone.

3 I don't know.. I've heard of that but can't remember what action to take besides replacing the speed sensor.

My guess as to the stalling problem is you have a really dirty or malfunctioning IAC valve, a screwy TPS, or something is unplugged, maybe a vac line or an electrical connector.

As to your last question, certain problems the PCM detects will immediately illuminate the MIL.. like a misfire, or a missing gas cap.

Other problems, the PCM will detect, and store. If it detects the same problem again (or a certain number of times,) it will illuminate the MIL. P1000 is a common pending code people see without the MIL being on.

 

[Superhereaux]

P0720
output speed sensor
circuit malfunction


If i have a speed sensor problem, how is the speedometer still working?

is your car auto?

 

[Rickey_Bobby]

it was an auto, it has a TR-3650 in it now.
...and none of these flagged my check engine light...

 

[RandyStinchcomb]

it was an auto, it has a TR-3650 in it now.
...and none of these flagged my check engine light...

and which Output Shaft Speed Sensor did you use? the one off the automatic or did you get one for a manual trans?