need help bad!! STILL no spark to coil!!!

[billbraskey]

ok STILL cannot get spark to coil!! cannot figure out why!!!!!!! ive tried everything!!!! (85 mustang gt) dont no what to do! the only thing i think it could possibly be is the wiring harness wich was cut and spliced together beween dizzy and ignition module...i tried to get a new one from ford.. they do not offer this anymore what else has duraspark ignition like this i can get this piece from in the junkyard?.. and i dont even think thats it anyways!! ive replaced ignition module coil dizzy.. took and tested module.. its good..i dont no what to do! using a light tester ive got power ware it needs to be! ive got power at the coil...what am i over looking!!?? maybe the wire from coul to dizzy is bad?? i dont see how that could be its practically brand new.. i don't no how that could go bad.. OR that autozone sold me a bad coil!? how can i test that.. ive got power at the coil it seems using light tester.. ..what else is there!!

 

[vristang]

I doubt I would be much help for you so here is a big fat

BUMP

Did you make any changes to any thing under the hood before the problem started?
Have you made any mods?

You may as well answer these questions up front because they will be asked.

Maybe a search for posts by jrichker will find something similar to what you are dealing with.

Good Luck
jason

 

[billbraskey]

I doubt I would be much help for you so here is a big fat

BUMP

Did you make any changes to any thing under the hood before the problem started?
Have you made any mods?

You may as well answer these questions up front because they will be asked.

Maybe a search for posts by jrichker will find something similar to what you are dealing with.

Good Luck
jason

yes i have mods.. have hardly drove car since made...stock rebuilt shortblcok.. gt 40 irons e cam edelbrock performer rpm intake..heddman longtubes .. and the car always started perfectly fine.. but i WAS messing wit the wiring wen this happend...im about to start hiding my wires..but i dont think i unpluged anything i shouldnt have!? ive looked a million times..i cannot figure it out!!
ok i stated this in my last post...the ONLY thing i can think of is.. the wiring harness connecting the dizzzy and the module wen i unwrapped it for the first time it was liek cut in half before??? or somthing.. and was all reconnected... ok follow me here people..the green wire that is suppose to go from to coil negative was either connected to somthing else or never connected at all... the wire that does go to the coil negative is pink.. and comes from a grey connector in the main harness on the driver side.... i thought maybe the harness was connected wrong so i re did it .. no luck.. i swaer ive tried it every wich way@! i cannot get spark to coil!!!!! im so frusterated.. i cant get that part of harness from ford... the guy at ford couldnt give me alot of help.. im stumped!! and its holding my project up big time .. its been going ona couple months now i really dont no what to do?! is my car justt never going to start again??? what do i do .. what am i over looking any ideas at all!what else could it possibly be! maybe i bought a brand new bad coil??? maybe the coil wire is bad? wich is brand new.. i kinda doubt it...if anyone on here can help please do! thanks alot..

 

[billbraskey]

p.s what does bump mean?

 

[pjc600]

ill help

had the same problem, i found that the ground to the module was bad. i remade it to a clean ground on the fender well, it sparked so hard i found that my coil wire was bad by getting lit up by thousands of volts, still feel it accel super coil ohhhhhhh if that dont work i have a few other ideas

 

[Saleen0679]

p.s what does bump mean?

A bump is just a short post that 'bumps' a thread back to the top of the forum where it will be seen again. You'll also see it as TTT (To The Top).

 

[vristang]

I agree with the above post. Checking grounds is a good idea since the car has been sitting a while.

Bump-
by making a post on your topic I "bumped" it back up to the top of the 5.0 tech forum. Gets you more visibility.

Another thing that might help is a post that another member makes quite often. Do a search by member on jrichker. He has a post that will take you step by step through a "cranks but no start" troubleshooting guide.

 

[billbraskey]

had the same problem, i found that the ground to the module was bad. i remade it to a clean ground on the fender well, it sparked so hard i found that my coil wire was bad by getting lit up by thousands of volts, still feel it accel super coil ohhhhhhh if that dont work i have a few other ideas

the ground to the module was bad? what do you mean? as in being bolted down???. hmm well if that is what you mean then that could be my problem .. maybe im confused tho ..cause the new module is not even bolted down ..somone told me it didnt need to be??
well thanks hopefully thats it ill try tomorow..

 

[FordGuy88]

There will be a ground wire off of the coil I believe or off part of the harness near the coil.(cant remember off the top of my head) What he means by bad is unbolt the ground if it isnt already, and use a wire brush to clean where the ground is being bolted. Also wire brush the ground wire and the bolt to hold down the ground.

 

[HISSIN50]

The computer grounds near the coil/battery.

Otherwise it seems to me that the TFI supplies the ground pulse to the coil (it gets constant 12 volts, so the ground is what is switched).

 

[jrichker]

AutoZone wiring diagrams

http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for 79-88 model Mustangs

Here's the one for your car...

 

[bcd]

get a meter and go point to point checking continuity between the computer and tfi module. thats what i had to do. it ended up being a bad fuse link on one of the lines

 

[pjc600]

here is another idea did you check to see if the distrubitor was sending the pulse to fire the coil???? i would check the pickup in the distributor. and as far as the ground idea goes i meant that it was dirty, very high resistance in the wire, the wire its self was bad and also the place where it hooked up at was all rusty

 

[Saleen0679]

get a meter and go point to point checking continuity between the computer and tfi module. thats what i had to do. it ended up being a bad fuse link on one of the lines

It's Duraspark not TFI. Unfortunately he's started a few threads on the problem so it's hard to follow and some key info is in an earlier post. You're right about having to go point to point though. It sounds as though someone swapped harnesses and now the wire colors aren't matching up. The wires from the ignition module are going to have to be traced and connected to their correct location.

here is another idea did you check to see if the distrubitor was sending the pulse to fire the coil???? i would check the pickup in the distributor. and as far as the ground idea goes i meant that it was dirty, very high resistance in the wire, the wire its self was bad and also the place where it hooked up at was all rusty

He's already replaced the distributor, ignition module, and coil.

 

[jrichker]

It's Duraspark not TFI. Unfortunately he's started a few threads on the problem so it's hard to follow and some key info is in an earlier post. You're right about having to go point to point though. It sounds as though someone swapped harnesses and now the wire colors aren't matching up. The wires from the ignition module are going to have to be traced and connected to their correct location.
He's already replaced the distributor, ignition module, and coil.

Very interesting. I wondered about the Autozone diagram since he said Duraspark somewhere. Not having any first hand experience with 85's, I took for granted that the AutoZone diagram was what he needed.

The following diagram is for an 83, it sounds more like what he already has.

I would look for 6-8 volts on the coil where the red/lt green wire connects.

I would also look for 12 volts on the white/lt blue wire at the ignition module on the diagram.

 

[Saleen0679]

The ignition section looks almost identical between the two with the exception of the R/LG wire going to the EEC power relay in the 85 diagram. The rest of the section looks electrically identical. I also thought there was a ballast resistor inline with the ignition switch which I don't see.

 

[billbraskey]

There will be a ground wire off of the coil I believe or off part of the harness near the coil.(cant remember off the top of my head) What he means by bad is unbolt the ground if it isnt already, and use a wire brush to clean where the ground is being bolted. Also wire brush the ground wire and the bolt to hold down the ground.

hmm i still don't undertsand this exactly.. i dont see any ground of my coil...there are suppose to be more than two wires?...ware does it go to?

thanks for all the good info ..working on it.

 

[jrichker]

The ignition section looks almost identical between the two with the exception of the R/LG wire going to the EEC power relay in the 85 diagram. The rest of the section looks electrically identical. I also thought there was a ballast resistor inline with the ignition switch which I don't see.

Ford used a resistance wire in place of the ballast resistor. Notice it says resistance wire under the block that says ignition switch.

 

[Bad92GT]

hmm i still don't undertsand this exactly.. i dont see any ground of my coil...there are suppose to be more than two wires?...ware does it go to?

thanks for all the good info ..working on it.

ah boy.. theres a + and a - side to your coil.. + meaning hot.. gets power.. - means ground.. therefore the - (neg.) should be grounded by some means of a ground.. check it

 

[90FRANKENSTANG]

I HAD THE SAME PROBLEM WHEN I DID A 4CYL TO 5.0 SWAP. I FOUND THE HOT WIRE I WAS USING WAS SWITCHED OFF WHEN THE ENGINE CRANKED. (SAME AS THE RADIO AND OTHER ASSY) MAKE SURE IT IS HOT WHEN THE STARTER IS CRANKING.