Hei/msd coil mod problems

FIMotorMX-3 · Post by **FIMotorMX-3** » September 16th, 2006, 11:53 pm

So I followed the instructions to a t and I also had some guidance from a few of you guys while doing it. I still have problems. The car idles all over the place. If the car idles high i.e. 1500-2000rpm, it's nice and smooth. But it shouldn't be that high. If it drops down to a normal rpm, about 900rpm (still high) it pulsates. Bouncing between 200 and 900 rpm. I figure I might have a little timing issue due to dismantling the disty and it needs to be adjusted but it also seemed like tps issues. Occassionally the rpms would drop to 0 on the tach while i'm cruising at 80mph. It's not the tach, i added the resistor on the tach wire. At first I thought it was the tach acting up but the other day the rpms dropped to 0 and the car was still running. Injectors were still spraying at 80mph but the car was not firing. You could smell the engine flooding yet I wasn't going anywhere nor was the tach showing any rpms. I downshifted expecting to have to pull the car off the highway and when I did so, my rpms jumped back up to a normal spot when I dropped to 4th. WTF? Has anyone experienced that before? I'm completely lost with this one. The set up seems to be wired correctly and my misfiring that was occuring before the mod has been fixed I think. Haven't put that many miles on the car since doing the mod. Maybe 5-700 total. But I am backfiring a lot. Not major but you can hear the popping in the exhaust. Backfire usually occurs when the car is slowing down and I'm letting the car drop to below 2000 rpms without engaging the clutch/taking the car out of gear. I also forgot to mention that the other day I was driving to work. It was raining out and I stopped for gas after driving the car for about a mile or two. When I tried to restart the car after filling I couldn't get the car started. I tried about 20 times. Right when I was about to give up and call the tow truck, I gave it one last shot and the car started like nothing was wrong. Tempermental B!7c)(...

PATDIESEL · Post by **PATDIESEL** » September 18th, 2006, 12:45 am

I haven't had to do the mod yet, but it def. sounds like a wiring issue or something in the tach signal. If the signal is not there the sparks will not fly (if they did then I'm quite certain you'd need a new motor so thank Mazda for that). I'd start from square one and recheck everything. You are sure to find something that looks amiss and then have a place to start diagnosis. I'd start with the disty, focusing on the cam sensor. Funny tach signals, funny idle and no fire on the freeway all point to something in the cam sensor.

Post by **Custommx3** » September 18th, 2006, 9:25 am

make sure its grounded good!!!!

Also, did you dissasemble the disty?
Did you remove ot cut thg internal ignightor?

hgallegos915 · Post by **hgallegos915** » September 18th, 2006, 11:53 am

argh mine startwd acting up and its probably bad grounding. :/ it drives fine and when i floor it.. PRRRPTTT PRRRPPTTT ROOOOOM ... eh ill rewire the whole thing.

hgallegos915 · Post by **hgallegos915** » September 18th, 2006, 8:00 pm

fyi i fixed it. it was wiring problem. I hope that was it.

FIMotorMX-3 · Post by **FIMotorMX-3** » September 18th, 2006, 8:36 pm

I completely removed the coil from the disty. I cut off the post that connects to the coil and i rtv'd the connection at the power tower as well as the point where i cut the post. I am assuming that the three metal prongs that connected to the coil were the internal ignitor that is supposed to be cut. Since I removed the stock coil, do those three prongs need to be cut still? I grounded the Sheet out of it.. it's mounted on a metal bracket like gro's install, grounded through the center holes as well as one of the four prongs on the hei was a ground. I guess I could retry the grounding it. I have been driving it sparingly and expected to check tdc and throw a timing gun on it as well. I'm assuming that disassembling the disty could have effected the timing as well. Does anyone know the wattage of the resistor needed for the tach wire? i know it was a 1000 ohm resisitor but there are different wattages. I'm assuming the cam sensor is one of the wires running off the harness on the disty. I'll do a search on that later. Thanks for the info and let me know if anyone thinks of anything else it might be.

ariesdude · Post by **ariesdude** » September 18th, 2006, 11:56 pm

The stock ignitor needs to be disabled - it needs to be taken off the circuit entirely. If the stock ignitor was bad to begin with and is still in the circuit - it will affect the new module's operation.

I used a 1kohm 1watt resistor.

patto · Post by **patto** » September 19th, 2006, 10:48 pm

i had the same prob but i new it wasnt my wiring or the way i grounded the module cos i always make sure things are dun proply it was the cars stock grounding pionts so i just run a new ground going from the battery to the same wall the hei was on that seemd to fix it but id still like to redo al the ground piont just to sure

hgallegos915 · Post by **hgallegos915** » September 19th, 2006, 11:27 pm

read my thread. same problem..well sorta.

FIMotorMX-3 · Post by **FIMotorMX-3** » September 20th, 2006, 12:19 am

I'm in the process of getting ready to move over the next few days so the car is parked because I'm so busy with work and the move..

But I'm definately going to go through the wiring. I'll also make sure I disable that ignitor. The car has never done this before wiring this mod. I thought by removing the stock coil it automatically disabled the ignitor but I'll take it apart again and make sure all that is diconnected properly and see if that's the problem. While I'm doing that I'll get the car to tdc and make sure that the timing is correct. I'll also go over the grounds, although I grounded the sheet outta that thing. If all else fails I have plenty of pavers in my yard. I'll be sure to aim right at the windshield when I throw one.

FIMotorMX-3 · Post by **FIMotorMX-3** » September 27th, 2006, 8:54 pm

Well tonight I jacked up the car and brought cylinder 2 up to tdc. The rotor was no where near the number two ignition wire. I'm wondering how the thing was running at all no less 80mph speeds.. the entire disty cap and rotor were covered in what looked like soot.... I disconnected the internal ignitor. loosened the screw to adjust the rotor and reassembled. The car started up and idled nice and smooth but at 2000 rpm. I took it for a ride for about a half hour and the car was ok. It had some misfiring at first but after about ten minutes or so it stopped. Rpm was fluctuating a lot at idle after about 10-15 min of driving. I finallly brought the car back and let the car idle in the driveway. rpms dropped to 900 and surged between almost 0 and 900 rpm almost stalling out completely multiple times. Something is up but not sure what. I still haven't redone the grounds or put a timing light on the car yet. I have to borrow the timing light and it was getting late to start rewiring things. So the problem is still not resolved but I located a couple problem so I'm narrowing it down. Does anyone know why there is so much black dust (soot maybe) inside the disty cap. The whole thing was coated. This is new since I've done the hei and coil mod.

sampsonmx3sv · Post by **sampsonmx3sv** » September 28th, 2006, 9:51 pm

New cap and rotor will solve that. The first time I did that mod my spark tower was too deep and the rotor was hitting .

FIMotorMX-3 · Post by **FIMotorMX-3** » September 29th, 2006, 12:44 am

I'll try that out and see how that works. I''m assuming that you are talking about the rotor hitting the tower that's causing the soot inside the cap. I'll give that a shot. It's cheap enough. Hopefully that's causing the misfire and part of the crazy a-- idle? One could only hope. I'm assuming the rotor hitting and not spinning freely could possibly cause a sporadic fire... I don't know. I've been up way too long and I think I could convince myself of anything at this point.

tehbrookzorz · Post by **tehbrookzorz** » September 29th, 2006, 11:43 pm

Also, sounds like you might benefit from checking your plugs.
Since your timing was so far off, I'd bet the fuel mixture to some of your cylinders was well, off...
So that might not be contributing to the best conditions inside the cylinders, and your plugs may require attention.
Just a guess, I haven't had this issue, yet. (hopefully never will)
Aside from that, if your plugs are grungy, a shot of Lucas Upper Cylinder Lubricant/Fuel Injector Cleaner probably wouldn't hurt either, should clean up the tops of your cylinders and the valves.

I wonder if that could have throw off your timing belt at all.

Of course, do the usual check for vacuum leaks, bla bla, and checking TPS and IAC positions may be wise.

I can't wait for my KLZE.

Custom_V6_Limited_SE · September 30th, 2006, 3:56 am

Next time you run it, pop the hood and listen carefully for a clicking sound. If you hear one, it is sparking out somewhere (most likely in the disty).