Intermittent Spark - Coil to Distributor

[AnthonyR23]

Hi, so I replaced some parts over the winter, including accufab tb, powerpipe, and pmas meter.

I was having issues in the late summer last year with the car stalling when hot. So I assumed it was the TFI module, and replaced that aswell as the parts above.

Cranks but doesn't start.

I also purchased a new cap and rotor as well as the new tfi module. I hooked up a timing light from the coil to the main wire in the middle of the distributor and am getting a intermittent spark.

Still can't start it, wondering if the coil could be intermittent?? would this be the next likely, I have fuel pressure, it's cranking good, new tfi module, cap and rotor, and wires a pretty new.

Any thoughts would be great. cause I'm tempted to go pick up a coil, but don't wanna waste money.

Thanks!!

 

[AnthonyR23]

Still Can't Start... Checked engine off trouble codes...

21 - ECT out of range
24 - IAT out of range
81 - AIRD
82 - AIRD
96 - Fuel pump circuit monitor

24 seems like a new one, from what I remember... not sure what that is?

 

[RydeOn]

get out your DMM..


check primary resistance between Pos and Neg terminals on the coil
resistance should be 0.3 - 1.0 ohms

check secondary resistance between Pos term and coil wire terminal
resistance should be 8000 - 11500 ohms

repeat secondary resistance test between Neg terminal and coil wire terminal
resistance should be 8000 - 11500 ohms

check resistance to each terminal and ground(coil case)
resistance should be infinite

 

[liljoe07]

What he said!

You also might want to look into testing the PIP sensor.

 

[AnthonyR23]

So, I didn't get this message till I got home, I picked up a new coil from canadian tire and just installed it, tried to start it and same thing. Probably shouldn't just throw money at it. I am getting pretty frustrated. Would failed pip cause the intermittent spark? It's rainy and crappy out so not gonna do much. But not really sure what is going on. Any help to get this thing going would be great. Have a cranks but won't start checklist printed out and is sitting out in the garage.. Have tried to work through the steps.. but I don't seem to be getting anywhere.. Thanks

 

[HISSIN50]

Where are you getting stuck in the checklist? It is the most reliable way to figure out the issue.

 

[AnthonyR23]

I agree it is probably very useful for most situations. but I think my situation could be slightly different. So following the checklist.. step one is to check for a bright fat blue spark. I replaced my cap and rotor, wires are new, I just replaced the tfi module and ignition coil. So I turned over the key and my dad put a screw driver in the end of the cap wire from the coil.. and as I turned it over.. he got a bunch of quick blue sparks. Then we hooked up a timing light to the same spot and am getting intermittent spark.. It sparks a few times in a row but is intermittent. So on the checklist, would I go to #2 no spark, or go to spark #3. On the checklist I have basically replaced everything from step #3 with spark. Just wondering if anyone has had similar issues? I am thinking ignition module or pip. Would either cause intermittent spark. If someone could direct me to which step on the checklist I should be at that would be great.

Or help in any way! Thanks

 

[AnthonyR23]

So should I be referring to the no spark list... number 2 on the checklist? I am getting spark but not consistent from coil to distributor with timing light, and the coil is good, old one probably was too, wasted money on this part. Was hoping it would fix the problem. But same thing. Shouldn't I be getting consistent spark from the coil to the distributor. And is the no spark list what I should be referring too? Would PIP sensor have anything to do with this.. I would think not since it is in the distributor, and this is a problem from coil to distributor. Ignition Module or something? Anyone ever have to place the stock ignition box/module?

 

[liljoe07]

Spark starts from the PIP sensor. Coil is the last component to get a spark signal. Minus the cap rotor and wires and plugs.

Personally I would look hard at the PIP sensor. Check the inside of the distributor. Look for contact from the vane wheel to the PIP sensor.

 

[AnthonyR23]

Okay.. well I didn't know that.. so that helps.. So I know that, throwing money at it isn't always the best, but I'm not sure what else it could be, if the cap and rotor, wires, plugs are good, tfi module is good, as well as the coil. So I guess, since I have gone this far, a re-manufactured distributor isn't that much further. May pick one up tomorrow and see if that helps. Thanks..

Is there much else it could be... ??

 

[AnthonyR23]

???

 

[liljoe07]

You can buy just the PIP sensor itself. Just have to tear the distributor down. If you don't have the tools, then you may need a machine shop to press the gear off.

Another possibility is the ECM. You can eliminate that by removing the spout plug and re-doing you spark test.

 

[AnthonyR23]

same problem with spout removed.. so does that pretty much point to the pip sensor.. and anyone know what type of things you would experience while driving if the pip sensor was on its way out? Cause had some stalling and rich conditions, I guess if all cylinders weren't firing that would do it.

 

[AnthonyR23]

So today, I stopped at part source, picked up a pickup/ pip/ hall effect or whatever it's called.. pulled the distributor, took it apart, including pulling the gear, and spacer thing. Put it all back together. cranked engine to 10 degrees, pulled a plug to make sure air was coming out.. and it was at tdc. Then made sure the distributor was pointed to 1.. turned it over and still getting no spark.

I am so frustrated.. gonna give up for a bit before I take this thing out back and shoot it..

Anyone wanna buy a 88 mustang gt convertible with new 347 rebuild, trick flow heads, trick flow intake, powermax 2030 cam, 5 speed, accufab tb 75mm, anderson power pipe, pmas velocity meter, quarterhorse software, wideband o2. New coil, new pip sensor, new battery, new mini starter, new tfi module, new cap rotor and wires.. Less the 10 km on new motor. Had running last year. Can't start since tb, powerpipe, pmas meter, and ignition components.

Or any advice on getting this going would be great.. Cause feeling like I have a piece of garbage in the garage. Thanks for any help. Not putting any more money into this thing.. way too much spent!

 

[AnthonyR23]

Sry about last post, just really frustrated.. gonna take a break from it for a few weeks, hopefully I can return some of these parts, as the old ones are probably fine.... I actually used to like working on my mustang, making changes and noticing the difference, but since this new engine, I haven't had it running right so I just am starting to loose the enjoyment of working on it..

 

[liljoe07]

Ok, I thought your spark was intermittent.

Check the #4 wire on the TFI for voltage with key on, and while cranking. Should be around battery voltage.

Check all you grounds also.

Is there an MSD box installed? Or other ignition box?

 

[cschwier]

Bumping this one.
Just wondering if u ever found the problem. I have experienced the same problem for over a year now with intermittent spark from the coil. I have basically bought the entire car over again with all the parts and its still there. I can drive mine somewhat though. Just jerks and misses. The timing light on the plug wire from the coil misses even with the msd box. Intermittent to? All new engine wiring harness too as well as all sensors engine and fuel system. The problem also came on worse and worse over time in my case.

 

[Xkuzme1]

Bump back up. I’m having this too. Totally intermittent.
X

 

[Xkuzme1]

Update:

My car was built with two switches below the dash and a start button.

I noticed that if I held down the start button before I flipped the switches It would occasionally fire off. If I could get it to fire off just right, the car would start. I started thinking about it, and it sounded like a lack of voltage or a bad ground.

So I left the switches flipped and started poking around. I noticed that when I wiggles the wiring loom that was close to the ignition coil, the fuel pump would prime (like it would when the ignition switch was flipped just prior to start). So I cut open the loom and started wiggling each wire individually. When I wiggled a black wire with a secondary color (white I think), it primed again... and every time I time I touched it it primed. I chased it down to a small plug and beyond the plug was a ground. I took apart the plug and cleaned it. Plugged it back in and taped it back together and it solved all my issues. As a matter of fact, the car runs better, idles better, and drives better.

If it gives me any more trouble, I’ll just remove the plug and wire it straight to ground.

I hope that this helps someone in the future.

Cheers