528i: car wont start without clutch to floor, clutch is fine

[LavaBurns]

My 528i's clutch has about 60k miles on it. It drives fine, though with the self adjusting clutch (SAC) bullshit, I'm not sure how much life is left on it.

My clutch has always engaged at about 3/4 of the pedal travel. Even now, the clutch engages at 3/4 pedal travel; I can shift gears without issue under all circumstances.

Unfortunately, lately I've been needing to shove my clutch to the floor with great deal of force to get the starter to crank. I suspect there is some kind of "clutch engagement sensor" that has gone bad, though my bentley manual makes no mention of a "clutch engagement sensor."

The issue first manifested when I drove from 100 miles west of Denver to Los Angeles in a day. Since that day, I've had to put the clutch to the floor without significant force. The problem got worse while I was camping in the Santa Ynez valley. I was parked on a hill and started the car. Though the car was rolling backward, I let off the clutch with the car in first gear (stupid? yes). The car stalled, but I realized my error immediately after and reengaged the clutch. I can't see the possible relation between this incident and my "clutch engagement sensor," but since this incident I have definitely needed to put significant force behind my clutch to start my car.

Remember, everything is fine once the car is actually started.

Anyone have any ideas?

[sikteer]

fluid leak?

[TyroneShoe]

If I am not mistaken, there is an electronic switch on the clutch pedal that needs to be triggered for the car to start. Previous posts about clutch stops discussed this in more detail. Your switch probably either got moved somehow or is failing.

[cpatstone]

yes, there's a switch. I tried to be clever and pull out the clutch stop, measure the thread, and replace it with a hex head bolt. Point is to stop the clutch travel just after you disengage the clutch. Got that from this or another forum. Boy am I clever... right up to the point where I discovered that with the ideally adjusted clutch stop bolt, the pedal doesn't go far enought to engage said clutch switch. :rolleyes

[540IForMe]

yes, there's a switch. I tried to be clever and pull out the clutch stop, measure the thread, and replace it with a hex head bolt. Point is to stop the clutch travel just after you disengage the clutch. Got that from this or another forum. Boy am I clever... right up to the point where I discovered that with the ideally adjusted clutch stop bolt, the pedal doesn't go far enought to engage said clutch switch. :rolleyes

Lol.

OP, check the switch this man speaks of. Clutch safety switch it's called in some cars.

[LavaBurns]

The switch had broken off. At present it's held on my wire ties and duct tape.

[blatant]

I wonder why I dont have one...thats wierd. I can start my car in gear if I wanted. Maybe the prev owner disabled it.
How did the switch break?

[Bryans1stBMW]

me too!

[cnn]

I wonder why I dont have one...thats wierd. I can start my car in gear if I wanted. Maybe the prev owner disabled it.
How did the switch break?
In your case, the P.O. bypassed it.
Yes there is a safety switch right above the clutch pedal.
Crawl and look underneath the dash and you will see it.

Chances are: the switch failed, so the P.O. bypassed it, therefore you can start your car in gear.

[NNY528I]

See Section(page Number) 612-8 in your bently manual, the section entitled, "Clutch Pedal Control Switch, Replacing" This is on book 2.