MSefi.com read only forum (Jan.15,2018)

MsII 3.57
LC-1 Wideband
EDIS 6 pack
1981 DeLorean
3.0 swap PRV.

I have been having intermittent starting issues, and sometimes it seems the motor bogs down as well.
When I posted my last log, Matt pointed out that I had a random misfire.
Now when the engine is cold it starts up very well, when it's warm it requires it to be encouraged to start.
IE: cranking and cranking.

We pulled the car into tha shop and tested fuel pressure which tested good, but when we hooked up a test light to the spark plug wires we noticed a random loss in firing from the wires.
First we pulled the fuse for the ecu and still had a random spark loss. The car was pumping fuel, and cranking, just no spark.
We replaced the EDIS module back in January since it was bad.
We also tried a new coil and still had the same issue.
We have currant going to the EDIS coil. So I picked up a new VR sensor just to see if that could be it.
Hopefully today we could try that as well. However his only happens when the engine has been ran and is either warm or hot.
Is there another variable to look for?
I'm using TS for the tuning.

Thanks in advance,
Darryl

EDIS will produce a spark even when completely disconnected from MS, defaulting to fixed timing.

Right, we did disconnect the ms just to rule that out.
The EDIS was still having random spark loss.

Being that this is isolated to just the EDIS, how do I go about diagnosing it?
I've eliminated the coil pack and module.
I will try a new VR next, could there be anything else I may have over looked?

Oh on the wiring, I followed the MS instructions.
However the gray plastic clip that has the red/green wire on it, the 12volt
Supply. When I ground that out per the instructions it blows the fuse to the EDIS.
Could that be any sort of issue?

Not sure what you mean about grounding out the red/green wire. On my EDIS 8 setup with original Ford wiring colours, that is one of the +12v feeds to a coil pack.



If you did ground that the fuse would blow.

On the lower left hand corner is the plug, on that has a ground wire attached to a grey plug.
If I ground it out it does short the fuse.
I think they are the same thing. So a yes to what you posted.

I tried to use another VR sensor today. However it didn't fit and when I tried to use it, the car backfired.
Yikes!
So I put the old one back in and it ran just fine.
However it did have trouble starting but I haven't messed with any settings do to the fact of the spark loss when it's hot.
Should I test the wires at all? I know it's isolated to the EDIS, but I don't know my next step.

Thanks
Darryl

I'm guessing the ground (black?) wire from the coil connector should actually go to the capacitor (as shown in my diagram) which has been cut off. Is it pretty short?

I can take a picture and upload it later. It starts and runs without it plugged in. If I plug it in the the fuse blows at the EDIS. I'm wondering if there is a wiring issue that I'm missing, I wish I knew what it was for. This random loss of spark makes it impossible to figure out the starting numbers.

It's short yes. It just had a black wire hanging off of it when I got it.

Just to give you a short background:
I paid a shop a a lot of money, when the work wasn't done after over a year. I had the car returned and have been trying to sort everything out at work. So I'm going to have a lot of stupid questions, I may be a pest.

If the capacitor is to be added, is there a diagram to how it attaches? Directly to the motor etc...
And which capacitor would I use? And could this be the loss of spark when the motor is warm or hot?

Thanks again,
Darryl

Here is a picture, the capacitor wasn't one mine though.
Just out of curiosity, could failing VR sensor do the same only when the motor is hot?
Being that the motor is in the back, the exhaust is very close to the crank wheel as wheel.
But it doesn't act up for the most part while the car is being driven.
Once in awhile I will get a random miss.

We checked the gap and also made sure it wasn't getting too hot.
But it still has random loss of spark, not sure what to do...

The capacitor is there to reduce electrical interference. Not sure if the lack of it could upset the EDIS module.
As regards the loss of spark when hot, is the EDIS module getting very hot? If you can make the fault happen, there are cooler sprays available from electronics suppliers that would let you cool the module down. Same sort of thing could be tried with the VR sensor. But first make sure it's not the power or ground to the EDIS module failing in some way.

It shouldn't be getting hot. It sits on top near a vent, that and the coil pack too. The only thing that would get hot is the VR sensor. We were able to get the muffler moved back a bit. Do there is about 3-1/2 in. distance if not more from the VR sensor.
Yesterday when I ran it and let it idle I noticed a drop, like the missfire was there once in awhile.
I will
Check the grounds and power again. I did find a loose ground for the MS unit.
every so often it popped its fuse. Turned out the ground was bad. The Edis is grounded in another location. I'll try those tow options first.

Thanks!
-Darryl

Ok they tested the power and ground here at work. When it acts up it still is a signal and ground at the wires.
Maybe it is the VR sensor? It does seem likes it's having more trouble starting now. Last night I had it out and it wouldn't start after a much longer time. Usually 5-6 cranks and it fires up. Last night it was nearly 10 min without spark.

If the VR is going bad, would I still be able to see the RPMs register on tuner studio?
Because I believe I checked for that and saw that the VR sensor was still picking up the crank wheel. Unless it was a bad signal?

Thanks,
Darryl

Another update:
Plugged the laptop in and watched it crank when it would t start.
The rpms were still
Showing. It dropped as low as 1 and as high as 179.
So the sensor is still sending somehing to the EDIS and Ecu.

I had replaced the module already, unless its faulty?
But this only happens when the car is hot.

Could it be the coil, and not the module, that's got heat problems?

We checked that too.
As soon as the car acted up in the garage we unplugged the coil and plugged in a brand new one. It was doing the same thing as well. Also the coil and module are right next to each other. They are mounted behind the driver seat away from any real heat. The VR is about 3-31/2inch away from the muffler.

I decided to start pulling the wiring apart just to physically run through.
Two grounds seemed loose after I cut the tape around the harness.
But they are pretty far away from the exhaust as well. On sits under where I has the coil and module mounted. The other sits on the passenger side valve cover.

To add to this, when I first installed this back in 2009, I never had this issue with random spark loss.
I sent it out to a shop and after they had their hands on it, it seems to have started then. But I have gone through everything, litteraly. And not internet litteraly lol, real litteraly.
I did do a google search a few times, and some people have had the same issues with those ford veichals, mainly Rangers.
I have the wiring pulled out now. Won't get a chance to go back in until Sunday evening.


However any ideas are welcomed! I did pick up a second VR sensor if the spark issues are still there.

Thanks again, this is a puzzle huh?
-Darryl

I finished going through all of the wiring that deals with the EDIS.
I fixed a ground wire which seemed loose. However I don't know if it came loose from me taking everything apart, or if it was already loose. But it was the ground for the module.
I reattached everything and found the car wouldn't start.
Looks like the shop that installed the VR sensor didn't do that good of a job at the connector for the VR sensor. So I fixed that as well. So got the car running and I let it run until it warmed up to 215 degrees. Shut it off and it started right back up. Let it sit for about 15min, and no start again.
The only thing noticeable is after I let off cranking, the very moment I let the key go (sometimes) it tried to start. I get a signal spark and that's it. Then after some more cranking it fires up.
I have pulse going to the injectors so it's reading the wheel. Just not firing.
It's very frustrating. Unless the module is faulty?
I swapped out the coil and it did it regardless of which coil I had in.
The VR sensor is the only Ning I haven't swapped or replaced but it's sendin a signal to the computer.
Or could it be wrong?
The only thing about the module is this only happens when hot, and the module, or EDIS system lacks any temp sensor.

Ahhhhhhh!!!!!
-Darryl

Forgot to ask too.

I had to run two new wires from where the VR sensor is to about half way into the harness...
Basiclly the wires going from the module have a shield around them. Being I wasn't able to save he other half of those wire the other half lacks the shielding.
However the car did start and run well at first.

Also when I pulled one spark plug wire the metal clip that status to the plug itself came out. Just to make sure the car started after my VR wire replacement I started the car. After a short time it ran poorly.
I checked the coil when I pulled the wires. I found corrosion on the connections.
Could the corrosion be causing the starting issue when hot?
I'm going to replace all the spark plug wires and clean the corrosion.
Should I get shielding in the meantime?

I wrapped the wires in about 4 layers of electrical tape together. I also wrapped a silver wrap that is suppose to keep hem cool since they run near the exhaust. Then I wrapped them in a plastic cover followed by another layer of tape.


Or the shielding will be needed?


Thanks,
Darryl