Troubleshooting intermittent starting issue

[JeremyJames]

Good morning,
The heat is already hitting us pretty hard in Florida. Other than the heat, I haven’t noticed a sequence that causes the issue of intermittent no start.

I get in the car, I prime the fuel pump, every time. Sometimes she will start without any hesitation, others she will click a few times. The click is coming from the starter, not just one click usually a few clicks with no start. Then I will turn the key off, and then all the way to ignition and she will crank up just fine.

I have a brand new Genuine BMW key, a brand new optima yellow top installed 2 days ago. I also have a brand new Genuine BMW fuel pump that has less than 2,000 miles.

My hunch is the starter solenoid, but I am not sure how to troubleshoot eliminating the solenoid or eliminating the starter as the issue. I have confirmed all wiring is snug and tight.

If I am accurate on the solenoid being faulty, what is the best manufacture to go with? If it’s the starter, I assume Genuine BMW is the way to go?

Thank you for your help and Happy Fathers Day to all of those great dads out there!

[sapote]

1) measure batt with voltmeter before starting. If less than 12.6v then it's not fully charged.
2) Car total mileage? Old starter might have pitted solenoid contact on the moving copper bar, not the solenoid itself. Disassemble the solenoid and clean up the pitted bar.
2.1) make sure the cable connections from jumper post on fender to the starter are good, you might need to remove cable at the jumper post and sandpaper to clean all surfaces.
3) could also cause by "weak" EWS internal relay: Jump EWS connector pin1 (I think pin1 and not pin2) directly to 12v source and it should crank every time.

[old///MFanatic]

If it's never been changed and you have had a decent amount of start-ups out of it, it's likely the starter. M3s are kinda hard on starters.
You need to weigh the options. Starter is a time comsuing job (often people replace hoses while they're back there too). I don't even mess with the solenoid anymore, if I'm in there I'm doing the whole enchilada at that point. Just replace the whole thing one and done. FCP Euro lists the Valeo as OE. Although I swear I have seen another. If you go with it from them it's Lifetime warranty, free shipping and the Valeo does not need a core charge to return iirc. One less hassle. If you buy the solenoid and the motor goes out later it's just not worth it. As a part that is used daily the non-BMW labeled OE starter price is rather inexpensive comparatively.

https://www.fcpeuro.com/BMW-parts/M3...6&b=9&d=600&v=

[JeremyJames]

If it's never been changed and you have had a decent amount of start-ups out of it, it's likely the starter. M3s are kinda hard on starters.
You need to weigh the options. Starter is a time comsuing job (often people replace hoses while they're back there too). I don't even mess with the solenoid anymore, if I'm in there I'm doing the whole enchilada at that point. Just replace the whole thing one and done. FCP Euro lists the Valeo as OE. Although I swear I have seen another. If you go with it from them it's Lifetime warranty, free shipping and the Valeo does not need a core charge to return iirc. One less hassle. If you buy the solenoid and the motor goes out later it's just not worth it. As a part that is used daily the non-BMW labeled OE starter price is rather inexpensive comparatively.

https://www.fcpeuro.com/BMW-parts/M3...6&b=9&d=600&v=

Thank you for this! I have a $1,500 rolling order with FCP, I added the entire starter. No sense in breaking down the intake to replace solenoid and the motor be faulty.

What are some of the items that should be replaced while replacing the starter? I will definitely be cleaning out the ITBs while in there. Are there any sensors, orings, or hoses/lines that I should be replacing preventatively?