Trouble shooting-?No sparks!!!

[T3tone]

I am trying to get the EDIS working in limp home mode without the mjlj connected (fresh install). The only spark i can get is on the odd occasion after cranking i get a single spark as i release the key! Gonig by suggestions in this post http://picasso.org/mjlj/?q=node/720 i have checked a few voltages and got the following.

voltage across VR sensor wires while cranking = various reading between 0.004 and 0.010volts!!
coil trigger wires while cranking = 0.45v on both
PIP line from module ignition on = 12v
PIP line from module while cranking = 0.4v

Im guessing its the very small readings from the VR sensor thats a problem, while turning the engine by hand the voltmeter reads slightly higher figures between 0.012 and 0.050v

With ign on im getting a constant 12v at pin 8 on module connector and centre wire on coil pack but 0v on the coil trigger wires.

Any help would be appriciated.

cheers,
Tony.

[rmaddock]

Tony,

Sounds silly, I know, but try swapping the connections to the VR sensor around. I was 100% certain that I had them right when I wired in my EDIS but nothing worked. I swapped them over and it fired first time.

It's worth a try. Of course, if you took a complete loom off a single car then this won't be the problem.

Good luck.

Robert.

[T3tone]

thanks for that mate will try swapping wires round. just spotted a post which includes all voltage readings of a working set up so should be able to sort it if i dont have any success.

[sierra2dr]

just spotted a post which includes all voltage readings of a working set up

I can't see the wood for the trees can anyone spot this post with all the readings? thanks

[scalefour]

just spotted a post which includes all voltage readings of a working set up

I can't see the wood for the trees can anyone spot this post with all the readings? thanks

Yep, that`d help me out too

[alexander]

http://www.autosportlabs.org/viewtopic. ... ight=#8152

i think this is the thread which you guys are looking for

[sierra2dr]

http://www.autosportlabs.org/viewtopic. ... ight=#8152

i think this is the thread which you guys are looking for

Oh thanks a million Alexander! I'm just saturated with different searches to be done,got no spark at the moment. And the DGAV has a small tube at the base plate (distributor vacuum advance),and I have to travel 90 miles tomorrow to collect a welder....grrrr,no time!!!

[scalefour]

http://www.autosportlabs.org/viewtopic. ... ight=#8152

i think this is the thread which you guys are looking for

Cheers Alexander and MartinM I wont be starting my install til XMAS (pressy from the wife) and info like this could prove a mental health saver.

[alexander]

you're welcome lads.

now sierra, let me jump in and ask what you are saying about the carburettor? i just want to make sure you realise that you cant use that vacuum advance takeoff for the MJ. you can, however, just blank it off with a little rubber end cap, but you do need to find a source on the manifold for the vaccum signal, preferably a point on the top of the manifold, so petrol doesn run down into the tube.

alexander.

[sierra2dr]

Yep,I was thinking that blanking it off but still thinking of where it should go. I have found a vacuum take-off from the manifold,I'll do pictures later

[brentp]

All-

I've updated the installation guide to include voltage / signal checks. Thank you for the contributions!

http://www.autosportlabs.net/MJLJ_V4_ve ... _Operation

[sierra2dr]

Well here's the tube coming from the weber DGAV

So plugging it would be best.

you do need to find a source on the manifold for the vaccum signal, preferably a point on the top of the manifold, so petrol doesn run down into the tube

Here's a picture of the vacuum signal from MJ to the manifold

I am now suspecting,that the trigger wheel is too small and the VR is not picking up a signal

[brentp]

That reference location should work. Was port freshly installed, or was it existing? Does the manifold also have a connection for a brake-booster?

Ideally your sensor should be square to the teeth, with a close to 1mm gap. If your engine runs smoothly with no misses, then it's probably 'close enough'.

[alexander]

sierra, re the trigger wheel, aside from brents comment about proximity and angle, it looks like your trigger wheel is a bit thin. that would likely not be a problem if it were not mounted flat against the crank pulley. seems to me that the trigger wheel is no more than 5mm thick? or thereabouts,so i am guessing that the relatively massive crank pulley right next to it is preventing the VR from experiencing a sufficient swing in magnetic field, to create a voltage spike.

there may be other issues, but one way of dealing with that would be to take the pulley off, and drill holes right through the crank pulley to match the trigger wheel. tedious, yes! should take about an hour on the drill press, based on my experience. i am assuming it is welded to the pulley? if it is bolted on, then spacers to make it stand off 5-10mm would be even easier.

regards
alexander.

[alexander]

and, yes, just put a little rubber blanking end over the tube on the carby. that is for vac advance for sure, and you obviously dont want air being drawn in there.

re the vac takeoff to the MJ. based on other posts here over time, might be a good idea to make sure the tube goes up, rather than down, lest petrol collect in the low point of the hose.