1993 325i Huge Problem

[lemons111]

Problems: Car does not stay on, rough idling, hard brake pedal.
It all started after I had left the car for about three days in the cold without using it. I had started the car up once for about 30 seconds and it was fine. Then the following day I decided I was going to drive it and when I fired it up, it only stayed on for about 5 seconds then unexpectedly died out. So I tried to start it up again but it did not respond. After draining the battery I called it quits because I knew that I had flooded the plugs. I cleaned the plugs because they were full of gas and were very dark, which I was quite surprised because I changed them 2 weeks prior to the problem. I tried to start it up but it only caught fire for about 1/2 sec. then died out. Finally with the help of some starting fluid and cleaning the plugs again, it finally started. However, it does not stay on if I stop giving it gas. After I let the gas pedal go it idles up and down and finally dies out. Also, I noticed that the brake pedal turned very hard after the problem. I checked the hose that goes from the air intake to the brake booster and it seemed fine. I don't know if the problem is a vacum hose or sensor, but if anyone has had this problem or know of it PLEASE HELP!

[16th hippy]

if you are flooding the plugs out, it could also be an ignition problem. does it have a distributor or a coil pack, and if so are those components in good shape? Sounds as if the fuel is getting there, but not spark.

[supervisor1886]

All plugs are evenly black? or just some of them? Weak spark on all of them. looks like its either the pick up coil (any of the crank, cam position sensor, or the actual pick up coil if there is a distributor) or shorted out coil (if theres just one), or your ignition control module, or a relay that activates coils (if you have several of them)

Please describe what type of ignition you have

[lemons111]

Originally Posted by supervisor1886

All plugs are evenly black? or just some of them? Weak spark on all of them. looks like its either the pick up coil (any of the crank, cam position sensor, or the actual pick up coil if there is a distributor) or shorted out coil (if theres just one), or your ignition control module, or a relay that activates coils (if you have several of them)

Please describe what type of ignition you have

The car was overheating so I replaced the water pump. But at the time I replaced it, most of the coolant soaked the front of the engine. And also, when I was bleeding the radiator, the steam and eventually the coolant shot out at the engine also. But once the water pump was fixed everything seemed fine for about 2 weeks, then this problem emerged. There is a sensor just below the water pump that I saw when I replaced the pump. I dont know if it is the crank sensor or cam position sensor. But that sensor got a shower of the coolant.
The car is a straight six with six coils, each coil over the individual spark plugs. All spark plugs had turned dark. I don't think there is a distributor. It's always a pain to change the spark plugs cause I have to take all the coils out. But I'm wondering if it is the sensor that is below the water pump that is bad, I'm sure it is the crank sensor, but I'm not 100% because I don't have the book. It was pretty cold here in Chicago when I had first attempted to start the car when it failed to start. But the city has gotten very pleasant weather mid 40's for the time of season and it is also a good time to start the car. I have not messed with it, because I still don't know exactly the problem and I know the people here are very informative. But somehow that sensor is on the back of my mind.

[lemons111]

But note, the car does start.

[lemons111]

Forgot, Thanx

[supervisor1886]

That sensor is the pick up coil (or the crank position sensor). It is a n actual coil (small in size) that induces current when a small steel peices on the dumper passclose to it. It causes the computer to fire the coils. Usually this unit fails from heat, corrosin, etc. and it usually results in hard starting, soothy plugs and hard miss at different speeds. That might as well be your problem,. Did you scan the computer for codes? Sometimes when that sensor wont cause any codes unless it completely shorted out and dead. (keep in mind your ignition systems is still kinda operational), but instead different codes for ignition can pop out.

I would defenatly see what the computer is registering. But the crank sensor is defenatly the first thing on the list. (they should not be very expensive)

[lemons111]

Is there a website where I can purchase one? Thanx for the good info!

[supervisor1886]

Just go to a parts store or a junk yard. But first check online how to get all the trouble codes from the computer.
For GM cars a crank sensor like this is about $30 canadian. For yours should be closer to $60. You could take it to the dealer or maybe a parts store like Auto zone-they should be able to test it, before you spend any money on it.