Few weeks ago the car would run fine only after being jumped. Took out for a test drive and parked it. Tried jump starting again the next day and would not turn over. Got a new battery from BMW and was finally able to hold its charge but car still won’t turn over. Pulled apart the back seat and noticed the fuel pump wasn’t turning on so I replaced it. Still won’t come on.
This is everything I’ve done so far:
Replaced Fuel Pump
Replaced Fuel Pressure Regulator
Checked fuses and fuel pump relay
Replaced CPS
New Battery
New Alternator
Open to more ideas or any help on what it might be. I’ve searched about every forum and youtube video I could find and can’t find exactly what it could be.
Thanks!
Just a bit of confusion for me - Car "turning over" means the starter is cranking but the engine wont start. - Car starting means it will start and run for a certain amount of time (indicating it will fire and at least briefly run) (meaning a variety of different problems).
If the starter is cranking and the car is not firing - then I would look for fuel pressure on the rail - if fuel pressure is there - then check that you are getting spark at the spark plugs. If not- move back to the coil and check that you are getting power to the coil to ignite the spark..
I would begin there.
I’ve checked the fuel pressure and it seems to be ok. There was no spark when I checked.
Would the coil have anything to do with the fuel pump not running too? Sorry I’m a little new to the game on this kind of stuff.
Fuel pressure at the rail would mean fuel pump is working.
The starter cranks - so you have power to starter.
No spark mean no fire (cant ignite the fuel) - so I would check the coil next (this is the single cylinder on the passenger side with one spark plug wire running to the distributor cap) - Is there power to the coil? Should be 12V if you have a meter.
To check for spark
Remove one of the spark plugs, and reattach the plug wire. Hold the plug wire using insulated pliers, and let the threaded bare end of the spark plug touch a grounding surface (any exposed metal area such as a bolt).
Ask a buddy to turn the key to start the car - you should be able to see a bright blue spark at the end of the spark plug. If you do, your coil is fine. If you don’t, your coil would be the next thing to check.
Last edited by 95BMWIC; 01-16-2019 at 05:56 PM.
Alright, I’ll check that and let you know what happens!
I pulled out a spark plug and got no spark so I tested the coil and got 0.08 on the two outside, and 6.14 on the inside. Not sure what it’s supposed to be at.
First - I'm assuming you checked to make sure you have voltage to coil -which means no fuse or electrical issue to that point. See the pic below - the red wire on pole #15 (it covers the 15) is were you can read voltage. The red wire in the photo is an additional wire were I have my volt meter hooked up - your wire is probably black - just measure volts at the + pole)
coil.jpg
Next you seem to indicate you checked the resistance between the two poles (1 - and 15 +) correct? And you got .08? that seems real low or .8 ohms? This is a measure of the "Primary resistance" in the chart attached below. To test Secondary resistance you use 15 (+ pole) and the center
I looked up the Specs - here is what the Bentley states: Replace any coil above the specs listed in the table so any reading above .50 ohms (6 cylinder) Primary or 5000 ohms Secondary.
Bentley Coil resistance.jpg
I wouldn't recommend going out and just replacing it yet (unless you have a buddy with a known good one) - double check the ohm meter and then I would probably try seeing if you could arch a spark either at the coil or at the distributor cap - same process as spark plug - just hold the wire out a bit and have someone crank it.
If its not a strong spark (resistance too high) it wont ignite the fuel.
Sorry, Yes I did read the number wrong. It was fluctuating between 0.7-0.9ohms from 15 and 1 and from center pole to 15 I got 6.14ohms.
I could not get a spark from the coil when I tried the other day.
Currently tied up on what to test next.
Thanks for your help!
Last edited by DALLINe92; 01-17-2019 at 12:45 AM.
From what you are saying above (the Ohm readings)
As long as you have power to the coil (around 10-12 volts)
AND
If you cant get spark from the coil - I would replace the coil.
I would just double check spark from the coil by arching it before spending any more money ..
Let us know if that fixes your issue..
Last edited by 95BMWIC; 01-17-2019 at 12:49 AM.
no spark when you pulled a spark plug and set it against the valve cover? just asking, not sure how you are checking for the spark?
No e30s again.
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