[Cordog41]

Hey there guys. As the title states I have been having start solenoid heat soak issues. The problem started last year when the oem starter began not cranking once the engine was hot. I was able to limp the car around by tapping on the solenoid with a piece of metal. I then purchased a new one from fcp euro and replaced it. This held up for a few months until it began the same symptoms. This time I tried wrapping it in a heat blanket but it seemed to do the same thing. So now yesterday I replaced the starter again since I had a lifetime warranty with fcp euro. I took the car for a spirited drive and let the car sit while I got some food and come back out the same thing again. I pulled out my trusty piece of metal and with one tap was able to get it started again. I am getting tired of replacing starters at this point just to have to do the same thing again. I am also making sure to buy the oem bosch units.

With all that said my first thought is now just that I either A) need to reduce the amount of heat under the hood or look into a remote starter solenoid that moves the solenoid away from the heat. Has anyone else had this issue before? For reference I live in Az and my oil temps are routinely in the 235-250 range. I am thinking maybe I just need to invest in a mossleman thermostat and setrab oil cooler to get these temps down. I do already have an oem thermostat and oil cooler but id doesn't seem to get the job done as soon as I drive more than just cruising at low speeds.

[335i54n]

its obviously not the starter and besides that it on the cold side not near the exhaust. you got other issues or installation problems, obvious one would be check the ground.

[Cordog41]

Are you referring to the engine ground cable that is on the drivers side under the starter area. I did replace that as well a while back when I replaced the first starter last year. I also replaced the crank shaft position sensor under the starter last year and changed both camshaft position sensors this year. Hell I also just replaced the battery with a new 95Ah one and the alternator too. I even measured my battery voltage at the positive terminal jumper post under the hood to see if the engine bay was getting enough power. I had around 12.8 volts when I did this. If there are other ground cables I should check then by all means let me know.

[335i54n]

yeah thats the main ground, you could put a redundant ground also. the main power feed for the starter meets at the jump point terminal. I would double check your connections and try voltage drop testing both wire to the starter

[Cordog41]

So I checked the positive cable that runs past the start and checked voltage. I was getting 12.5-12.6 bolts on different occasions but the starter still won't crank. It has a very distinct single click. I'll try and attach a video of it. It is a single click then I get the fault saying the ignition is on but engine is not. I also checked the resistance with an ohm meter from the jumper point to the alternator so that it would test the wire where is runs past the starter and still got 1.5 ohms and 12.6 volts but just a single click and no start. I also removed the manifold to make sure the positive cable was in full contact with the starter solenoid and no nuts/washers in between it and the starter. I'm starting to think maybe my new starter from fcp euro is locking up when it is hot and able to start fine once cool. To be clear this only happens once I have been driving the car for a while with oil at the 235-250 mark. I just had it happen on a road trip while stopped for gas and that was less than ideal.

[335i54n]

sound like its an amperage problem and volt and ohm test do nothing. 3rd starter for same problem, doubt it. probably corroded connection/wires where it cant carry the amp to fully power the starter

[Cordog41]

So then from what your saying is it is probably the cable that carries the power to the starter and alternator that is bad? That is the only thing I can think off that could be corroded as I haven't replaced it yet. Visually is looks ok but I wouldn't fully know unless I remove the wire sheath and look at the wires themselves. What other wires do you think it could be?

[Cordog41]

Ok I just performed a voltage drop test after watching a video and on initial start up the voltage drop was .28-.30 then went down to a constant .10-.15 With that knowledge I am led to assume that my cable is pretty bad and a miracle that it is still even charging/occasionally starting. Is this correct?

[Cordog41]

Just wanted to update you guys, I just replaced the positive cable that is in the engine bay and will report as I drive it more and get some heat in the system. Hopefully this solves it 🤞

[BIGREDe90]

Did replacing the Positive cable fix your issue? I am troubleshooting the same thing right now. Grounds were replaced, starter ordered but while I have it apart, it would be nice to hear if changing the cable helps. Thanks for your reply

[Cordog41]

I haven't driven the car a lot as it needs an alignment but I think it did fix the issue. I took the car out for a drive yesterday (about 30 minutes and drove it hard once up to temp) then had to run to the store so I let it sit for about 15-20 minutes. After that I got in to start it and it started just like normal and sounded faster when starting. So in the end yes I think it was the issue. Thank you guys 🤙

[Cordog41]

Welp, I’m back to square one. The car is back to its old ways. After doing a lot of city driving the other day with the oil temp sitting around 230-235 the car would not start after sitting for 45 minutes. I checked voltage in the engine bay and got 12.8 volts. My radar detector inside was also reading 13 volts from the cigarette outlet. I then decided for the heck of it to use my leaf blower and blow air onto the starter for about 5 minutes. After this it started right up like nothing happened. I am again suspecting it is the starter solenoid that is getting too hot and not working. For perspective I have now replaced the starter twice, positive engine battery cable, ground cable, camshaft sensors and crankshaft position sensor. All parts are from fcp and oem. Not sure what to try at this point. I’m thinking of just ripping the starter out yet again and working some magic with heat shield wrap. My other thought was that maybe the crank shaft position sensor that I got from fcp is bad? Any help would be appreciated.