89 325i - When Cold, Long/Hard Starts

[bcrdukes]

Hey guys,

I'm stumped and need some help please. I have an 89 325i. I purchased the car this way but whenever the car sits overnight, or after driving, 15 - 20 minutes, I run into a long/hard start issue.

Basically when the engine is cold, I'll have to crank the ignition for a good 5 - sometimes maybe 15 seconds before it fires up. When the engine is still warm, it fires up no problem. I've checked the following so far:

1. Fuel pressure. It's fine. I even replaced the FPR with a spare one known to be working and in addition, installed a fuel check valve at the fuel pump.

2. Air. There are no vacuum leaks. (Not that I can find anyway but visually looking at the intake boot (AFM-throttle body) there are no signs of cracking.)

3. Spark - I've only so far checked my cap, rotor, spark plugs, ignition timing, and spark plug wires. I have yet to check the coil (not sure how to.)

4. Unrelated but battery is charging properly at 14v and sitting at 12v when the car isn't running.

Any leads? Remember - the car fires up okay when the engine is still warm.

Thanks!

[bmwstephen]

starter?

[bcrdukes]

Hmm...but it only happens when the engine is cold.

[SpecM]

what exactly is it doing?

is it cranking, and not starting... or turning over too slowly... does ir just spin and spin or does it sputter and choke too?

[yert315]

throwing this out there: coolant temp sensor

[bcrdukes]

what exactly is it doing?

is it cranking, and not starting... or turning over too slowly... does ir just spin and spin or does it sputter and choke too?

It's cranking over a few times (maybe 5 or 6 times then fires up. It doesn't sputter nor choke.

yert315 - Why do you say the coolant temp sensor?

I did the stomp test - got code 1444 so no errors. Yesterday, I did the timing belt (indoors of course.) After letting the car sit for 4 hours without coolant, once we were done, refilled it - car started first crank. After driving it around to make sure it was okay after bleeding the coolant, let it sit for 20 minutes - back to square one. :(

[robsE30]

throwing this out there: coolant temp sensor

I would also point that direction for start. Since you have an 89 the ECU (Motronics 1.3) do not use the cold start valve anymore, instead it uses the Coolant Temperature Sensor to read the temp. When its cold the sensor readout will cause the ECU to adjust the injectors to spray longer. When warm it will adjust back to normal. For me it was the other way around. The faulty sensor cause the ECU to think its always cold so I ran rich. Its a $20 part so its not a big loss to replace it.

[yert315]

yert315 - Why do you say the coolant temp sensor?

like robse30 said, it adjusts the air/fuel ratio depending on the temperature of the coolant.

[bcrdukes]

Sorry for the bump but in case anybody is curious, turns out my injector(s) were bad. Replaced with the new style and works flawlessly.

[nomansland92]

I've been having the same problem and every thing i've checked is ok but i've never checked the injectures because the car runs fine. What type of injectors did you get and where did you get them.

[Morrison]

What kind of injectors are "the new style" ?