1995 325i won't start, was running great. new to site

[3050rpm]

Big Evil, many good points there, thanks for sharing them.

[Jetty]

Yes, thank you, great information. There is a grey female connector that is diconnected under the driver side fog light, I think this is the external tempurature sensor connector?

Also there is a disconnected grey female connector dangling around the windshield washer pump. The wire seems to only reach the washer pump; Now, the windshield washer is not working; however it is connected up; I think someone may have connected the wrong female sensor wires to the wrong male receivers on the washer pump and then just had an extra sensor wire and just left it dangling.

Both the ext temp sensor and the ambient temp sensor are reading -37.


Thank You again for your reply.

[Big Evil]

The temp sensors are what is called a NTC (negative temperature coefficient) thermistor (thermal resistor). Big fancy way of saying the change their resistance value opposite what the temp around them is doing. Very cold = high resistance, very hot = low resistance. -37 is the default cold setting indicating the highest possible resistance to current flow. This can be caused by a bad wire, connection/connector, or a bad sensor. You can test it by putting a digital multi meter on it (the sensor, out of the car) in the ohm setting (omega symbol). You should get a value, then pass it near a flame or heat source (warm it up) and the reading should go down. If so, the sensor itself is most likely good and you need to check the wires (you'll need a schematic for that). Otherwise get a new sensor, plug it in and see what happens. Oppositely if it reads like +174 all the time you have a short most likely bypassing the sensor. Stuff not being plugged in unfortunately happens a lot when things apparently stop working (it's just easier than fixing it in most cases. Sometimes its ok, but more often than not it causes other unforeseen problems that can really bite you in the butt. I'll tell you several stories about some of my various "ok crap that's what that does" stories sometimes :-).

[Jetty]

Hey thanks again. Interesting stuff. I can't wait to get it all straightened out. I'm getting ready to drive long distance. Car is still running good, the sensor issues are making me a little nervous for the long drive, nothing a few cups of coffee won't cure though :-)

[Kkriss]

Hi,

I have a similar problem with my bmw 325. It was running great, even long distances. I went away for a week and came back and hasn't been able to start since. battery is full, i even replaced it with a brand new one, but it doesn't even turn. it just clicks. i turn the key and it goes *click* *click* *click*. what might be the problem?

any help will be greatly appreciated. Thank you!

[David Mc]

Check the earth cable connections to the engine and chassis.