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Old 11-08-2012, 10:15 AM
rrtec's Avatar
rrtec rrtec is offline
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Location: TN 37174
Join Date: Sep 2008
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Mein Auto: 540i/6 4/99
Misfires with thermostat 139 INPA code

The last two mornings my 1997 740i has thrown a code and the temp guage has only been at the 10 oclock position. I plugged up the INPA and the car was throwing misfires on all cyls as well as a 139 thermostat output code. As soon as I clear the codes the temp guage reads normal and stays good until the next cold start the following day.

The car runs well although sounds cammed when first started so I understand the misfire codes, I am assuming that my sparkplug wells have some oil in them as my VCG need replacing and I have dealt with that before. But the 139 code puzzles me. Is this the sensor ontop of the housing or is the thermostat bad? The fact that when I clear the error the guage goes to normal makes me think its the sensor and not the thermostat itself.

I have attached the pages from the initial start up of the Smoothness and then when fully warmed up as well as a shot of the 139 error.. Sorry for the poor cell phone quality pics. Any help would be much appreciated.

Start Up:

After up to temp:

139 Error:

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2001 740il Sport- Needs maintenance.. Parts ordered..
2006 Volvo XC90- Kid Hauler
FC3S LS1/6Speed
1992 BMW K75s Cafe build

Last edited by rrtec; 11-08-2012 at 10:32 AM.
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