Hard to start when cold

[robmespeedy]

Car: 1989 325is
problem: hard to start when its cold.

Check engine light on. Checked for codes. found coolant temp sensor faulty. Replaced it. same problem ! same code. later found out that there was a faulty connection at the harness. fixed it! No more check engine light.
But car is still difficult to start when cold.

One day i had a hard time starting it. when it fired up i accelerated the rpms high. Check engine light flashed but then turned off. Check for codes the next day.
- O2 sensor control
- Vehicle speed sensor control

you think thats my cold start problem ????

[jlevie]

Cold starting problems are frequently caused by intake leaks. When cold the engine needs a richer mixture and the addtional air from an intake leak can lean out the mixture enough to make it hard to start. On a car this old every rubber part of intake is suspect.

[Mike325]

Do the I's have a simmilar cold start valve like the E motors do? My car (E) had the same problem and it turned out to be the thermal time switch. That sences the coolant temp and tells the comp to spray more raw fuel into the engine.

[Mastrcruse]

The es had this problem. I called autozone, don't know why but I did, he said that the bmw's are known for putting to small of gauge wire back to the battery so it tries to hard to get back to the battery but in the cold it tries extra hard and doesn't want to give much juice for anything.

[robmespeedy]

im starting to suspect the fuel pressure regulator.

[a3ternus]

Changed the main intake rubber hose going from the AFM to the engine
and got the starter professionally cleaned and repaired and that problem
went away,plus now it starts like a new bought car...try it! ;)
N.