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Tori Tori is offline
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Join Date: Jul 2016
Location: Pismo Beach, CA.
Posts: 677
Quote:
Originally Posted by wazzz View Post
To make it clear, the DME is actually the ECU. When you say you swapped the DME, I guess you mean the DME relay. If you have no spark, you don't need to try and swap the DME relay, since it has no relation with the ignition.
You need to check the basics. First make sure the ECU is powered on when the ignition is switched on. You can check this by listening in the engine compartment. You should hear the idle control valve (ICV) humming. If not that means the ECU has no power or is completely dead.

Next, if the ECU is indeed alive, you need to check if you have fuel.
If you have no spark, maybe you have no fuel either. In this case it would point to a failing sensor (maybe). The ECU won't allow any spark or fuel if it doesn't get proper signals from both flywheel sensors at startup. No spark no fuel is typical of a failing sensor or a failure of the IC inside the ECU that is used to format these sensor signals for the processor.

Okay.... here's where we are currently in this process.
-I have verified ICV is getting power. I can hear and feel it humming.
-I've verified i have power at DME relay on both pins, 86 and 30 (86 when ign. on)
-I've swapped coils with another Bosch coil (not 100% positive it's a good coil, but it's what i had. I do have 12v at coil.
-Checked ohm readings of speed and ref. signal sensors. 971k and 973k respectively.
-Pulled dist. cap to inspect, rotor looks fine, cap has normal buildup and does show wear on a few of the terminals - looks like rotor contacted a terminal at some point, but nothing looks excessive or beyond it being able to function. (at least to some degree). - I'll order new cap and rotor for later this week.


I'll pull the DME apart next and look for failed solder joints next.

Open to any other suggestions.
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Last edited by Tori; 12-21-2025 at 06:52 PM..
Old 12-06-2025, 03:02 PM
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