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Topic Review (Newest First)

  • 07-07-2009, 11:13 AM
    minetree

    Running... Better than ever...

    I put the new pump in and vroommmm!!! on the third try. So - new main relay, new ref sensor, new coil, new fuel pump, new filter, new fuel line. The car sounds like a chipped beast, and is even running a little rich... Thanks for all your help. MMinetree
    88 535i
    210,000+ Still Kickin
    Remaned Head, all stock.
    88 Mazda 323 4Banger
    168,000+ Still Kickin
    Terminal Velocity 113mph
    32miles to the gallon
    <img src="http://www.michaelminetree.com/DSCN0004.JPG"
  • 07-06-2009, 03:33 PM
    minetree

    Re: coil, relay and ref sensor now replaced...

    Oh - and I checked for power at the pump - it was there. When I disconected the hose from the pump there wasn't any pressure in the line... I'm on the way to get a new one.. Will report..Minetree
    88 535i
    210,000+ Still Kickin
    Remaned Head, all stock.
    88 Mazda 323 4Banger
    168,000+ Still Kickin
    Terminal Velocity 113mph
    32miles to the gallon
    <img src="http://www.michaelminetree.com/DSCN0004.JPG"
  • 07-06-2009, 03:29 PM
    minetree

    coil, relay and ref sensor now replaced...

    Still a no-go. After all the cranking I assumed it would have to be grossly flooded.. Opened the top up and looked in - nada.. Just a little bit of built-up fuel.

    So I puuled the casing on the fuel pump - it's the original pump with the factory crimp on it.. Maybe it's time to replace it, huh?Minetree
    88 535i
    210,000+ Still Kickin
    Remaned Head, all stock.
    88 Mazda 323 4Banger
    168,000+ Still Kickin
    Terminal Velocity 113mph
    32miles to the gallon
    <img src="http://www.michaelminetree.com/DSCN0004.JPG"
  • 07-06-2009, 12:20 AM
    TJ

    Re: I ran a meter on the coil and the ref sensor..

    For the coil, 5.5K on the high voltage side sounds normal. The low voltage side does have a very small resistance, it shouldn't be 0, but depending on the accuracy of your meter getting a reading of 0 may not be a problem. Your reading for the reference sensor also is probably fine. First verify that there is power to the motronic unit (main relay). Then if there is still no spark check for an ignition pulse by watching the voltage on the small black wire at the coil while cranking (it should fluctuate). If not, Motronic or speed/ref sensors are a likely problem. If there is an ignition pulse but no spark then coil or distributor is not working.
  • 07-05-2009, 07:21 PM
    minetree

    I ran a meter on the coil and the ref sensor..

    and got the readings in the previous post. They were off the normal values. I didn't know if there was any wiggle room with the resistance - or if it's not spec then just replace it. Thanks for the tips on the fuel pressure. My "smell" test was my down and dirty way of getting it done. Minetree
    88 535i
    210,000+ Still Kickin
    Remaned Head, all stock.
    88 Mazda 323 4Banger
    168,000+ Still Kickin
    Terminal Velocity 113mph
    32miles to the gallon
    <img src="http://www.michaelminetree.com/DSCN0004.JPG"
  • 07-05-2009, 05:02 PM
    super_eurobeat

    Re: Bad Coil, Bad Reference Sensor, Bad Main Relay???

    Well dont test for fuel smell....test for fuel pressure and look if your fuel pump works. Run a paper clip with the car off from pins 30 and 87 on the fuel relay, it will turn on the pump but it doesnt tell you how well it works. Go get a water pressure gauge from lowes or home depot, a 100 PSI one is more accurate since the numbers are spread more out, they have 200 and 300 PSI ones as well. Get a female T block, 2 male barbs with the outside diameter as the inside diameter of the fuel hoses, then put the gauge on the top. You will want to run something similar to teflon tape, i cant remember the exact name but its a yellow tape and its resistant to getting eaten by oil and fuel.
    You unhook the feed line going into the rail and will the bars and gauge screwed into the block, run the feed line going to the rail (not the return from the FPR) and run another hose, something preferrably from autozone (electronic fuel injection reinforced hose) and run that from the other barb to the fuel rail. This should run about 34 bucks after tax.
    You can get the hose long enough to run outside near the door but thats a good 30 dollars in hose, so you can get a friend to crank the car and see what your fuel pressure is.

    For spark, the reference sensors will test as is with no variables, all you need and from what you said, is a multimeter.

    For the coil did you test using the middle pin, to the terminal on the coil, in addition to a ground from the - on the coil to the frame rail? the coil needs to be tested in 3 spots using the multimeter, the bentley manual tells you how to check each one.

    All of this is fairly easy, with a multimeter you should be able to find your problem quickly, and with what i told you about the fuel, that as well.

    You can test a relay with a battery, some wire and female spade connectors, 30 is power in, 85 is ground, 86 is switch, and 87 is power out. Apply power to 85 and 86 to move the leg for power to flow, the main relay is a 5 pin however, the white relay.=============================
    Modified B&M race shifter
    MOMO shorty shift knob
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    Mason Engineering X-brace
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    520 front /750 rear spring rate-Eibach Race Springs
    Vorshlag camber plates
    Revalved Bilstein Sport shocks and struts
    Bridgestone Potenza G009 225/60/15 tires
  • 07-05-2009, 04:02 PM
    minetree

    Bad Coil, Bad Reference Sensor, Bad Main Relay???

    The old bimmer has been sitting where it died 7 months ago - and the oak tree that's above it has taken a toll... So I decided to finally figure out why I have a no start...

    The coil reads a very consistent 5880 ohms and occasionally 0.5 across the pins. Occasionally it reads 0. Replacement time?

    The reference sensor reads 1145 instead of the expected 960.

    I don't know how to test the main relay.

    I crank and crank it and can't get any fuel smell - even with my nose buried in the intake...

    The $65,000 question is - It looks like I have to replace all of these parts... But how did they all crap out at the same time? Is there anything else I should be looking at - or do I replace all this and then start guessing some more?

    Thanks - and hello to all. It's been a long time..
    MMinetree
    88 535i
    210,000+ Still Kickin
    Remaned Head, all stock.
    88 Mazda 323 4Banger
    168,000+ Still Kickin
    Terminal Velocity 113mph
    32miles to the gallon
    <img src="http://www.michaelminetree.com/DSCN0004.JPG"

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