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why is taking so long to enter closed loop?

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Old 12-24-2012, 06:58 PM
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Default why is taking so long to enter closed loop?

i have no DTC's
i checked my MAF, EGR, CTS and they all seem operational.
i have looked at how OBD II driving cycles work but its not really helping me figure out why its taking so long.

today i drove my car around town for 45mins and my temps made it steadily to 195F

My A/C does not work and my Rear Defogger either
so i dont know how to do a driving cylce without turning those both on.

i do enter closed loop but it seems like i have to turn my ignition off and on and off and on real fast back and fourth and then i finally get it to do it after the car has already been driving.

is this a known side affect of a possible ignition switch going bad?
 
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Old 12-24-2012, 07:54 PM
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How are you determining that it isn't in closed loop?
 
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Old 12-24-2012, 08:20 PM
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Originally Posted by rriddle3
How are you determining that it isn't in closed loop?
i got an OBD II device (elm327 bluetooth) and it tells me i have a "Bus Error: shorted to vbatt or ground" (only when the engine is running and not in closed loop)

whenever the engine finally goes into closed loop i can connect and get live data (no DTC's and 4 "Tests" have not been completed that would need be if i were to get an emissions test.

i have recently had the ECM, BRB, BCM and all fuses and relays under the hood and inside the truck all pulled out.

so it makes sense those tests are not complete but i drive several times today for 45mins, 30mins and two 15mins and each time engine was shut off.

when the ignition is in the "On position" but not RUN i can see (some) sensor data

i guess the only way i can tell im in closed loop is (when the obd ii) device stops giving me that error and finally connects.

i got really frustrated today because i did all that driving and couldnt connect that when i got back in my driveway i put it in park and cycled the ignition switch off and on really fast and then the device finally connected so i went out and got quite a bit a live data (and recorded it to)

for some reason the device detects when the ECM is in open loop mode and it gives that error
i think its a glitch in this device and it should work in open loop mode but it hasnt yet.
 
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Old 12-24-2012, 11:31 PM
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Sounds like a Chinese knock off scanner. My genuine Elmscan 327 never gives me an error, closed or open loop.

ScanTool.net LLC - Scan Tools, PC, iPhone, & Android based OBD-II (OBD2) Interfaces, OBD diagnostic software
 
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Old 12-24-2012, 11:42 PM
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I'm thinking you may have a bad engine coolant temperature sensor or bad O2 sensor that's making the pcm think it's in open loop when it actually is not.
 
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Old 12-25-2012, 09:21 AM
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Originally Posted by rriddle3
I'm thinking you may have a bad engine coolant temperature sensor or bad O2 sensor that's making the pcm think it's in open loop when it actually is not.
I think you might be onto something.

see the reason is (the scanner does work with ignition = on)
when i actually start the car is when its having problems.

when i actually did get the car into closed loop the scanner would read and i was able to pull alot of data.

you got me reviewing the data that i pulled and i see in every one of my screenshots i took (and i got alot over a couple hours of driving) that this specific data never changes.
here is a screenshot of it


now even in closed loop with engine running this sensor/data is stuck unlike its other two similar sensors/data

so it goes into closed loop like this so the actual problem (sensor/data) that was preventing closed loop might have stopped but still that sensor i have in red is still malfunctioning it looks like

my engine coolant sensor is working pretty good but i think maybe my intake air temp might be about 20F - 30F off of the actual outside air temperature

im gonna go outside in a minute and pull the data after the car has been sitting all night and compare temps.

i do know this is a clone sensor but its glitching out because i have another problem in my system in my truck somewhere ( i believe)

on a side note:
say you been running in closed loop for hours
if you turn off the ignition and then put it back run (engine off) is there any way this could ever be in closed loops still or is it mandatory that the engine always has to be running to be in closed loop?
 
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Last edited by tdbone1; 12-25-2012 at 06:16 PM.
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