Stopped working

spitfire50 · Post by **spitfire50** » Mon Nov 09, 2015 1:54 am

Hi,
My existing system has quit. It started as no start which I seemed to fix sometimes by moving the wiring. Other times I had to convert the ignition back to distributor to get to my destination. This weekend I pulled the MJLJ harness out and rebuilt it. When I re-installed it there was no start. I confirmed power to the coil pack, the EDIS, and the MJLJ. I also was able to swap the coil around so it isn't a matter of firing the wrong plugs. Also tried both polarities on the VR crank sensor. The last time I lost ignition the engine quit while running at idle shortly after a start. Does this trouble point toward a dying EDIS module? Or is there something else that commonly displays these symptoms?
EDIS4 MJLJ no recent changes to a working system that has run for several years.
Any ideas welcome,
Paul

spitfire50 · Post by **spitfire50** » Sat Nov 14, 2015 8:10 pm

Hi,
Got a chance to hook the lap top to it today. No tach signal shows, but the map sensor signal is there and it does show the advance for cranking speed. I tried reversing crank sensor polarity in case I have it wrong. I also have tried starting the car with the MJLJ unplugged and nothing. So I don't get limp home mode. EDIS trouble?
At 4°C I'm not anxious to do a lot of testing outdoors. It will be warmer tomorrow, perhaps then.
Paul

spitfire50 · Post by **spitfire50** » Thu Nov 26, 2015 4:35 pm

Well, another try. Bought another EDIS unit and installed it this morning. Still no spark. Converting to distributor makes it run. Tried both polarities of the crank sensor, and also swapped the coils: nothing. When I tried to check SAW and PIP the readings I got made no sense steady voltage on both PIP about 2.5 V SAW much higher. Of course I could only check them when cranking. I just went out and unplugged the MJLJ and tried the car, still nothing. So no limp home EDIS either.
Ideas please.
Paul

Alex B · Post by **Alex B** » Thu Nov 26, 2015 9:55 pm

Of course you can check functioning with a running engine. You can run dizzy and MJ parallel. Get yourself an extra set of spark plugs, ground them and hook them up to the MJ setup. Run the engine on the dizzy. Have the MJ setup also connected to current. This way it will be fully functional (or in your case, partly disfunctional).

Brent, please insert this rule into the guidelines for installation: NEVER REMOVE THE DIZZY IGNITION BEFORE YOU HAVE RUN MJ PARALLEL AND ARE COMPLETELY SURE EVERYTHING IS FUNCTIONING THE WAY IT SHOULD. Saves a lot of frustration and your starter engine

.

Alex

Post by **brentp** » Fri Nov 27, 2015 7:23 am

If it suddenly stopped working and you swapped out modules then the likely issue is a fault in wiring. I would run through the verification steps here:

https://autosportlabs.net/MJLJ_V4_vehic ... tion_Steps

As you've noted, the engine should run under limp home mode with the Megajolt disconnected.

Let us know what you find out!