96 e300d w210 - P120

[smk_texas]

Folks,
My 96 e300d (157k) acts up when the weather turns cold. Runs perfectly during summer . The temp fell to about 28f here in N.texas the last couple of days.

1. Last morning when i tried to start the car in the morning, it cranks but no start. The charge battery warning flashes followed by check engine electronics. The code i pulled was P120.

2. I kept cranking with the pedal pushed down and it finally started. Drives great no issues. If start i immediately after a drive it starts fine but after it is parked for couple of hours same problem again.

I checked the battery & alternator and all is good. So what does cold weather do to trigger the p120. BTW, it did the same thing last winter (2015) but luckily we didn't have much of a winter in N.Texas . So, any input on the root cause of this problem would be appreciated.

smk_texas