Car will not start - BMW Forum

Majin · 03-13-2006, 03:05 PM

My car died on my mom on her way to work thismorning. Had it towed home and been checking it out. First thing I thought was the fuel pump. So I Bought some starter fluid to see if it would start. That didnt work. So I pulled a plug to see if there was any visible spark. There was no signs any spark that I could see. Maybe the coil? it hasnt been changed since I have owned it. Everything else is fine with it.

Starmavin · 03-13-2006, 06:59 PM

First off: What year model?
Check all fuses, and relays. If all that is good, your problem could be the coil. One way to check if it's getting siginal is to take a test light and put it on the each lead as someone cranks, one or the other should make the test light flash. If it flashes, bad coil. If it doens't check your CPS (crank position sensor).

Numark318i · 03-13-2006, 07:20 PM

Check your vacuum lines. One of my vacuum lines was severed, the car died after the check engine light came out.

Majin · 03-13-2006, 09:10 PM

It's a 90 325i Convertable, all the fuses are fine but not sure how to check relays.

325eXTATIC · 03-15-2006, 11:43 AM

Cranks but no spark... My bet would be the Crank Position Sensor. I agree with Starmavin that you should check all the other aspects first, but when my eta did the same thing, the CPS fixed it right up, and in under 20 minutes total time! It is a sensor that sits in the bell housing of the transmission if I remember right, and there are two of them together. One is the CPS and the other is the Speed Sensor. If you have checked everything Starmavin has recommended, and you still get no spark, just dive in and buy a CPS. It comes off with one bolt (5mm alen bolt I think...) and pulls right out. Follow the wire up to the clip that is holding it to the frame or engine, pull that out, and follow up a little further to the connector. It pulls straight out, and installation is exact reverse of removal. VERY easy, and you shouldn't even need to put the car on stands or ramps, if you don't mind getting a little dirty on your back!

Hope this helps!

Josh W.

Majin · 03-16-2006, 02:31 AM

I was checking out the coil earlier, I get spark from the coil with a wire directly off the coil to a plug, but nothing with it running through all the wires. Does the small wire from the main wire to the distibutor cap run to the CPS? and would that cause it not to start? How much is this CPS? I'm going to pull off my distributor cap tomorrow and check things there too.

Majin · 03-16-2006, 10:11 PM

I'm not sure if these cars are made to do this or not, but when I crank the engine, the rotor under the distributor cap does not turn. It is also at the position to Cyl #6 which is the one with the extra wire to the sensor. Is the sensor supposed to recieve a signal before allowing it to turn? or could it be the timing belt.

Morgenster · 03-18-2006, 11:12 AM

Quote:

Originally Posted by Majin

I'm not sure if these cars are made to do this or not, but when I crank the engine, the rotor under the distributor cap does not turn. It is also at the position to Cyl #6 which is the one with the extra wire to the sensor. Is the sensor supposed to recieve a signal before allowing it to turn? or could it be the timing belt.

Um, if the timing belt's gone and you've been cranking it all this time, didn't you hear anything rattle or break? Cuz, if it's the timing belt, you may just be damaging your engine by cranking it.

Majin · 03-18-2006, 08:44 PM

I havnt heard anything rattle or break while cranking it over. I bought a small pickup up truck today and plan on pushing it into my garage in a few days. Then I will be starting to pull the engine apart and checking it out. If it is severely damaged, would it cost more to drop a diff engine in it or to rebuild it?

Numark318i · 03-19-2006, 01:47 AM

Dont u have an electric ignition. Theres no cap and rotor. atleast my M42 doesnt have cap and rotor.

Starmavin · 03-19-2006, 11:44 PM

If the rotor doesn't turn while cranking, look for a good or rebuilt cyl head, you have bent valves and there is no doubt about it.... sorry.

If you chose to rebuild the head buy new rocker arms, chuck every one that is over a bent valve. They are aluminum and get severely stressed when they bend valves, its not worth the risk of them breaking shortly after a valve job, because you have to remove the head to change them. Seen it happen....