Not starting when hot

[Andres]

Hello everyone,

I own a 1990 325 ic automatic. The car has 170000 miles and runs great. However, lately after I stop for a short time at the grocery store and then try to start the car, while the engine is hot, the key turns but the engine doesn't. A similar simptom as a dead battery. The battery is new, and in the mornings when the engine is cold it starts right up. Any sugestions?

 

[325i_Pilot]

You are turning the key to the start position while the engine is hot and the motor wont turn over at all? At first, it sounded like you were saying it wouldnt fire up, which could easily be vapor lock among other things, but if the motor wont crank over, hhmm let me think on that one.....

 

[Big Daddy]

So you turn the key to the start position and nothing happens? No click click, no nothing? You either got a bad battery or a faulty starter? Need more information or clarification

 

[Doughnut]

Starter motor solenoid getting to hot with engine heat, faulty starter relay?
Does it start once it has cooled right down again?
Weird.

 

[Andres]

Yes, once the engine has cooled it starts right up. When hot, turning the key does not even produce a clicking noice. Thanks for the help.
Andres

 

[325i_Pilot]

Definitely electrical, even if the starter motor gets hot it should still get power, and if nothing less make allot of racket or a disengaged humming spinning noise. So I would rule out a faulty starter (one thing you may want to try that has worked in the past for various vehicles that I have been around, is to lightly nock the starter with a wrench or hammer a couple of times then try to start it again to see if that fixes it, but do it a home. It’s really embarrassing to try crawling under a car at a gas station or employee parking lot). Now relays can act up due to high heat exposure, so replacing the starter relay would be a cheap way to start the process of elimination. Also, check your ground wire from the subframe to the engine block to see if it is in good condition, if not replace it, if its in doubt replace it. I bought a 6 wire performance grounding wire kit off of ebay for $20+ - that mounts at the battery or the subframe’s original wire connecting point, and the wires spiderweb across the engine to various points (E.I. distributor cap, intake manifold, fuel injector rail, head, etc.) for a more complete grounding connection and it put some real life back into my 325i. Here is a link to another of the same auction if anyone is interested. Took me about 20 minutes for complete installation. http://cgi.ebay.com/ebaymotors/BMW-...004QQitemZ140169139774QQrdZ1QQsspagenameZWDVW

 

[325i_Pilot]

I forgot , if those ideas don’t work then the culprit is probably your solenoid…

 

[Big Daddy]

Wow again, I have had a few cars that when the engine is hot the starter (old and worn out) would not turn over when hot, once cooled down the car would start right up. In my case I replaced the starter motor and the problem was resolved. I am not ruling out a solenoid, but first check to see you have 12 vots to the started when the key is turned on.

 

[Doughnut]

Wow again, I have had a few cars that when the engine is hot the starter (old and worn out) would not turn over when hot, once cooled down the car would start right up. In my case I replaced the starter motor and the problem was resolved. I am not ruling out a solenoid, but first check to see you have 12 vots to the started when the key is turned on.

Yourself and the 325_pilot have turned to custard...

 

[AWD_Guy]

My car was taking a really long time to start when I 1st got it...always started, just had to crank for about 5 seconds before it 'caught'...until 1 day on a trip to the corner store to pick up smokes, she wouldnt start back up when i returned, had to call my father for a push and we got her back home.

I changed the starter since it had over 200k on it, works great now.