In desperate need of help here - Page 2 - PeachParts Mercedes-Benz Forum

Boston Benz · #1 10-02-2011, 07:43 PM

I got sidetracked here for a couple of weeks but I'm back. I just measured the resistance of all three coils. Two of them are a year or two old and the third is brand new. All three coils measure 9.4Kohms (using a Fluke 88).

Can anyone answer how I'm getting 12 volts at the low voltage side of coil #3 but the plug isn't getting any power? I don't understand that one. The only thing in the way of the 12 volt supply and the plug, is the coil - and that's brand new. What is my next logical step?

Andras · #2 10-03-2011, 10:19 AM

Quote:

Originally Posted by Boston Benz

I got sidetracked here for a couple of weeks but I'm back. I just measured the resistance of all three coils. Two of them are a year or two old and the third is brand new. All three coils measure 9.4Kohms (using a Fluke 88).

Can anyone answer how I'm getting 12 volts at the low voltage side of coil #3 but the plug isn't getting any power? I don't understand that one. The only thing in the way of the 12 volt supply and the plug, is the coil - and that's brand new. What is my next logical step?

There are 3 measurements possible between 3 terminals of each coil, and you are only listing one.

The spark is triggered on the secondary (plug) side of the coil, when the ground is interrupted on the primary (low voltage) side.

dieselgirl85300D · #3 03-12-2016, 05:34 AM

I hate these threads with NO resolution!!

lsmalley · #4 03-12-2016, 06:22 AM

Quote:

Originally Posted by dieselgirl85300D

I hate these threads with NO resolution!!

The resolution was that he probably got rid of the car.

dieselgirl85300D · #5 03-12-2016, 08:55 AM

Mite just start with plugs

Andras · #6 03-12-2016, 09:19 AM

I would check the distributor rotor and cap with an Ohm meter. My 1994 E420 had similar symptoms and those parts were evidently burned out internally.

dieselgirl85300D · #7 03-13-2016, 11:57 AM

Pretty sure this E320 has direct ignition with coils and no distributor cap or rotor
Thanks

puzzler · #8 10-25-2016, 12:36 AM

Hey deanyl!
thanks so much for those wiring diagrams! Hope I spelled your name right..Ive got a fuel pump issue you just addressed with those diagrams! I can see if the FP relay sends power the fuel pumps must run. There is no other component between..Now Im curious how the ECU turns them off when the engine is not runnng..since there seems to be no pressure sensor ...some type of timer? Its gotta be in the system info..

These are broken down much more clearly than any Ive seen..

Ferdman · #9 10-25-2016, 11:31 AM

puzzler, deanyel's post was in September 2011. I haven't noticed any posts from deanyel in years, but have no idea why.

puzzler · #10 10-31-2016, 11:43 PM

yes thanks Ferdman, I was thinking of my own issue not his. But those wiring diagrams are awesome..What would my comment be, a cross comment? my bad of course..these chats have lots of info just by way of coments and references..