Transmission refuse to shift up in morning
#1
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2013 Black C250 Sport+
Transmission refuse to shift up in morning
This is weird but since the weather got colder in NY I've been having shifting issues with my 2013 C250. Whenever the engine is cold, the third gear refuse the shift up until it hits a little more than 3000 rpm. I am basically feathering the throttle, and the engine keeps on revving to 3000 rpm. All other shifts happens about 2000 rpm. Only in cold weather, before the engine warms up. But once it shifts at 3000 rpm on the third gear all the rests of shifts happen normally. May be tranny fluid not flowing right until third gear shifts or something? Not annoying enough to take it to the dealer but I thought it was WEIRD!
#5
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2012 c250 Coupe
Quote from page 128 of manual:
"Upshifts take place at higher engine speeds after a cold start. This helps the
catalytic converter to reach its operating temperature more quickly."
Page 127:
"The catalytic converter preheats for up to 30 seconds after a cold start. The sound of the engine may change during this time."
I knew pdf of the manual would come in handy one day haha
#6
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2012 C250 Coupe
Yeah, what Kevin said. Its not an "issue" rather just an annoyance due to big brother and cars needing to meet emission standards. Catalytic converters don't really start to "work" until they are warm, so the car keeps RPM's higher on cold starts until cat temps are within operating range. I usually let my car idle until RPM's drop to normal ranges on cold starts. But if you drive off before its warmed, you get unpleasantly rough shifts at higher than normal RPM's.