Loss of power

das86turbo · 01-01-2019, 08:21 PM

I have a 2012 335i xDrive. I'm struggling with a few problems. One is the P0128 code (coolant thermostat temp low) after having replaced the thermostat and FP. Also getting a low coolant level alert. Level is fine. I've bled system several times. Car doesn't get to operating temp. Recently, i experienced loss of power under acceleration. Seat of the pants tells me the turbos are not performing as they should. The check engine light came on. That problem cleared itself after stopping and restarting the engine. CEL cleared too. Is this an indication of a failing Vanos? My OBD scanner only shows the preexisting P0128 code. Is the Vanos code BMW specific?

vespa · 01-02-2019, 12:04 AM

So... you're getting thermostat codes after messing with the thermostat? And now it seems like the thermostat isn't working? I dunno man, before you go digging into Vanos, maybe check that the thermostat is plugged in.

juld0zer · 01-02-2019, 03:35 AM

Monitor coolant temp either thru the dash or OBD if you can (monitor coolant vs ambient vs oil temp), while the engine warms up. If it truly is a stuck open thermostat it will take forever to warm up to 90+*c.

Once you have confirmed suspicion of another stuck open thermostat you will need to remove it and inspect it.

01-01-2019, 08:21 PM	#1
das86turbo New Member 0 Rep 19 Posts Drives: M3 Join Date: Jul 2014 Location: Evergreen, CO iTrader: (0)	Loss of power - Vanos? I have a 2012 335i xDrive. I'm struggling with a few problems. One is the P0128 code (coolant thermostat temp low) after having replaced the thermostat and FP. Also getting a low coolant level alert. Level is fine. I've bled system several times. Car doesn't get to operating temp. Recently, i experienced loss of power under acceleration. Seat of the pants tells me the turbos are not performing as they should. The check engine light came on. That problem cleared itself after stopping and restarting the engine. CEL cleared too. Is this an indication of a failing Vanos? My OBD scanner only shows the preexisting P0128 code. Is the Vanos code BMW specific?
	Appreciate 0 Tweet Quote

01-02-2019, 12:04 AM	#2
vespa First Lieutenant 218 Rep 245 Posts Drives: 2011 335i Join Date: Dec 2014 Location: Thousand Oaks iTrader: (0)	So... you're getting thermostat codes after messing with the thermostat? And now it seems like the thermostat isn't working? I dunno man, before you go digging into Vanos, maybe check that the thermostat is plugged in.
	Appreciate 0 Quote

01-02-2019, 03:35 AM	#3
juld0zer Lieutenant Colonel 482 Rep 1,600 Posts Drives: Prev 135i 7DCT, Now 130i 6sp Join Date: Jul 2016 Location: 2153 iTrader: (0)	Monitor coolant temp either thru the dash or OBD if you can (monitor coolant vs ambient vs oil temp), while the engine warms up. If it truly is a stuck open thermostat it will take forever to warm up to 90+*c. Once you have confirmed suspicion of another stuck open thermostat you will need to remove it and inspect it.
	Appreciate 0 Quote