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Cold Start problems

1K views 3 replies 2 participants last post by  Mb_330Ci 
#1 ·
Hello everyone.

Have been experiencing cold start problems only in the winter. Summers and warm temps. No issues. When too cold or the car has stayed out idle for long in cold it won't start. The temperature gauge shots to red and remains for a while when turn the ignition to on position. The temperature gauge comes back to cold and then the fuel pump kicks in and lights on the dash flicker. The needle shoots to red again and stays there for a while. The whole process repeats a few times depending on how long the car stayed out in cold. Once the gauge settles on blue (as it should since the car is cold) the pump kicks in intermediately and dash lights flicker in between (not one continuous heesing sound as it should) once the dash lights have stopped then the car will start in one crank. I had a bit of leak in the coolant sensor in the lower rad hose. Replaced it and also did a coolant flush while at it. There is no check engine light and used peake tool to scan and no error showing.

Anyone with any ideas? Would really appreciate some help here. Thanks
 
#2 ·
I know this one, and the solution in my case wasn't cheap (replace DME). When you turn the key to position two (just before you go a bit farther to crank the engine), your "check engine light" should come on and the temp gauge should immediately go back down to blue. If this doesn't happen, it means the DME computer isn't online and the engine won't start. Sounds like yours loses connectivity for a while (temp gauge in the red, no start), and then comes online sporadically (temp gauge moves to left, pump primes, and engine starts). Mine would consistently not start in the cold for days, and then one day it would suddenly fire up. Check my thread here: http://forum.e46fanatics.com/showthread.php?t=957315 for the whole tale.

I would be curious to see if you could try the "hairdryer to heat up the DME" to see if it starts (take off the DME compartment cover in the engine bay and just blow the hot air onto the DME unit for a few minutes). I considered installing a hair dryer in the dme compartment rather than spending the $1000 to get a refurbished DME coded for my car :yikes: (just kidding).

See this thread for info on the company I bought the DME from: http://forum.e46fanatics.com/showthread.php?t=966802 . There are other options (as mentioned in the thread), but since you are in Canada too then RPM might be a good option for you. At least you can order one of their "off the shelf" keys-EWS-DME packages for your 325 while mine was a special order (MS45 ECU on M54 engine)
 
#3 ·
thanx for the reply. It helps to know that I'm not the only one with this problem. heating up with the hairdryer is certainly a good start as that will definitely say whether its the DME. i'll try that out over the weekend as see how that goes.

thanks again!
 
#4 ·
Hey Junglee. It might be your lucky day if the DME is your problem. I was looking at one of my favourite salvaged BMW parts websites and they may have a complete matched replacement set for your car - EWS, key and MS43 DME unit. It says the kit is for a 99-03 325, but check it out at least to see if it will work in your '04 car. If it does, it's an easy plug and play replacement fix for only $308 Cdn. The seller is in the GTA, and the url is http://www.ebay.ca/itm/Bmw-E46-MS43...145267?pt=Car_Audio_Video&hash=item2c6cc0f233
Mark
 
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