523i very hard to start

I have a 1997 523i which is very hard to start mostly when cold, if i keep cranking for 10 mins or so it will start and run perfect, any suggestions ?

Might try the temp sensor thats located on the engine head, that sensor gives the computer the info when to richen up the mixture and go lean when first cranking the car.

Originally Posted by poolman

Might try the temp sensor thats located on the engine head, that sensor gives the computer the info when to richen up the mixture and go lean when first cranking the car.

I would check this and the battery as well......

hello, had exactly the same problem. in the end after trying everything took it to bmw and they did a software reset on the car, that cleared the starting problem. it cost me £140.00

Thanks for comments , There is 2 sensors in the head just under manifold , which one is for the temp sensor?..... The one nearest front of engine looks new ... the other one has no wires connected, looks like 2 pin... battery is new , so far i have checked fuel pump and fuel lines , changed fuel fliter, pressure rail is fine, ,fuses,relays ,6 plugs etc..this is a prodject car i bought about 4 weeks ago and getting some TLC before it hits the road

Originally Posted by poolman

Might try the temp sensor thats located on the engine head, that sensor gives the computer the info when to richen up the mixture and go lean when first cranking the car.

which one there are 2 sensors under the manifold.

The sensor at the back of the engine is the one that the computer reads from. That one doesn't have any wires going to it you stated? If it isn't hooked up that would be a big reason it doesn't crank when cold.