Help! No heat?!
Its cold as **** here in the midwest and I have no heat.
At the same time this issue started -- check engine light came on, codes: P0116, and P0128.
The car runs fine -- and coolant does come up to temp 180-200F w/in 15 min of driving --- oil temps on the other hand do not get above 150 even on a 40 min commute.
My initial thought was thermostat? But could it be something else?! My other thought was if we have some sort of heater control valve -- as the car is warming up somewhat quickly -- and prior to this issue in the extreme cold it would take quite some time to come up to full warm -- however -- I can not find a part # or anything for this.
Lack of heat is evident when it is very cold, @ milder (20 degree + temps) its not as bad, but in the -20 we've had here recently in Michigan, which is when this problem first arose -- its brutal.
Thanks in advance!
Car is a W204 C63 AMG P30 (2009).
the fan does blow/and everything works as far as far as the various settings, air coming through the vents is not the same temp as external but it’s definitelt not warm.
https://driving.ca/auto-news/news/ho...heating-system
https://driving.ca/auto-news/news/ho...heating-system
Any idea what the engine codes mean? Assuming it means thermostat replacement ? Would that have a thing to do w/heat ... the car still comes up to temp (coolant), but the fans run from start up and continue to run for a few mins afterwards at full blast as well




I had that on my e46 M3 after driving it and letting it sit on a very cold winter night.
Your symptoms are leading me to an open thermostat. your coolant might get to operating temp (15min seems to be too long to me). but your engine oil isn't. Which tells me that all or most of the coolant is going through the radiator and is cooling your engine and the oil in the engine too soon.
What seems unclear is why your heater isn't blowing warm air as it should not even after 15min unless the sensor is bad as well.
P0116 Engine coolant temp sensor range/performance problem.
P0128 Coolant below thermostat regulating temperature.
Last edited by sventastic82; Feb 3, 2019 at 06:12 PM.
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I had that on my e46 M3 after driving it and letting it sit on a very cold winter night.
Your symptoms are leading me to an open thermostat. your coolant might get to operating temp (15min seems to be too long to me). but your engine oil isn't. Which tells me that all or most of the coolant is going through the radiator and is cooling your engine and the oil in the engine too soon.
What seems unclear is why your heater isn't blowing warm air as it should not even after 15min unless the sensor is bad as well.
P0116 Engine coolant temp sensor range/performance problem.
P0128 Coolant below thermostat regulating temperature.
thanks! I have a new thermostat so just going to replace it! Although giving. It a womp with a mallet would be such an easy solution !! it did happen after a very very cold night. Where is the engine coolant temp sensor located? Is this an easy DIY?
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