evo42

I've got a thermostat stuck open. Code was related to the car not getting to temperature. $106 for a thermostat from the dealer, $134 from Autozone (with a gasket). I'll check-out worldpac.

bars_sun

Ok, week later after temp sensor was replaced and message is on again. I guess at this moment I really need to start monitor temperature of the engine almost every time I drive. But I noticed very interesting behavior: no matter how I start off the stop - slow or fast - message always appears when I start off on the road where pavement is not smooth, i.e. it almost always comes up when car is jumping over pavement imperfections and accelerates at the same time.
As of right now I am planning to monitor temp and probably looking into bringing it to dealership to have PUMA case opened if they won't have a solution.

bars_sun

So, it's been a month since last time I got CEL with increased emissions. I do have now computer at hand connected to OBD socket where I can see cooland temperature (just to rule out that engine is not hot enough). Also last weekend I finally got around to clean MAF sensor (I highly recommend to do that for those who is very close to 100k). Coolant temperature is varying between 87-97C with AC on - it was pretty hot outside and AC was on so was the fan constantly.

Raheel312

Have you taken out the charcoal filter?? If so, put it back in, and see what happens.

beamerdude

my 530i had the same emission problem. i went to bmw at least six times throught 5 month period, they couldnt figure out anything each time, then finally the figured out the some kind of wire conected to the transmission was loose and damaged which was settinf off the emissios signs each time, my car also idled rough to when the sign came up, maybe check it

mwsu545i

Hello,

Would anyone have the part number for the 2004 545i coolant expansion tank? My tank also developed a crack, and I need to replace it. No longer under warranty, of course. I wonder if the same cause of the tank crack caused the return tube from the radiator to the tank to crack.

At first, I saw the cracked tube, and replaced it. Then, the next day, discovered coolant was still being lost, but now through the coolant expansion tank.

Any ideas? Thank you very much in advance!
michael

e6t.lab.rat

for the coolant expansion tank part #:

http://www.realoem.com/bmw/showparts.do?mo...hg=17&fg=05

for others that have the increased emissions warning check this DIY thread. it's a real simple and easy, let alone cheap repair that worked for me in solving my increased emission problem. good luck!

https://5series.net/forums/index.php?showtopic=85337

mwsu545i

[quote name='e6t.lab.rat' date='Sep 19 2009, 01:03 PM' post='1011782']
for the coolant expansion tank part #:

http://www.realoem.com/bmw/showparts.do?mo...hg=17&fg=05

thank you, sir, for your fast response!!! I've had to patch it for now.