no spark help

[Jocigar]

hey Guys, working on getting my 70 barracuda started after 15+ years sitting.   I took all the plugs out and turned in over my jumping the relay switch.   Now that I have oil flowing, there seems to be no spark at the plugs.  I don't remember about these cars too well since its been so long.   

So far, I found TDC on cylinder one by plugging the spark hole with my finger and made sure the wiring firing order was ok. 
I need to get a meter on the coil tonight.   
any advise on the order of trouble shooting? 
-Is there a kill switch on the tranny that cut power to coils? if so where?
turning the key has no effect on the starter relay.  I will measure if there is 12v going to the relay with key turned.

A few things dont work, wipers, headlights, blower fan... fuses are ok.   THanks!!

[Bullitt-]

Automatic tranny has an interlock switch that provides a ground to the relay so the car will not crank in gear.
If your not getting any power through the fuse box I would check the fusible link found between the starter relay and the bulkhead connector, usually a blue wire about 6" long.

[72rtchallenger]

if its cranking over and not firing you need to check coil,,ballast and ecu and possible the distributor

[dodj]

Do you have  'no spark' or 'no cranking'? The subject line seems to suggest no spark but the post seems to suggest you are not turning over the engine.   

[Jocigar]

I turned over fine after a few days soaking the piston chamber with oil.

its been raining a lot so no meter test yet.   

My concern was the trans kill switch (not samiliar with it) and if that would some how cut power to the coil should it not be working.  I am jumpering the starter relay since key is not working to turn over the engine.

Will post back once I go at it with a meter.   Thanks all. 

[barracuda7199]

on the starter relay there is a terminal for the safety nuetral switch. i think the wire color is brown if u look at the relay it should have a G beside that terminal. bypassing that terminal with a wire hooked to the ground on the battery might make the key work then. be careful if its in gear and it runs away we will go!! have u tried moving the shifter to neutral and turning the key?

[Jocigar]

Thanks for that, I will have a look.   

I did not try neutral.  truth be told after sitting for so long the button on the shifter would not go down, so I forced it and now the button is stuck down but did not release the shifter and I and now moving the shifter by lifting the lock mech with a screwdriver... another fix on my list.  Brakes are all frozen too, I want to hear it run before going further... step one for me.

[72rtchallenger]

on the starter relay there is a terminal for the safety nuetral switch. i think the wire color is brown if u look at the relay it should have a G beside that terminal. bypassing that terminal with a wire hooked to the ground on the battery might make the key work then. be careful if its in gear and it runs away we will go!! have u tried moving the shifter to neutral and turning the key?

that will get to crank with key unless there is another problem..
but that wont make it spark as the neutral switch does not kill the coil

[Jocigar]

OK guys, took 10 minutes at lunch with a meter.   Thanks for the jumper trick on the brown relay wire... it worked!

As far as voltage, I pu the negative on the battery and got 10v on both sides of the coil and 10v on both side of the resister.   Still no spark, however.   Any thoughts on my next step?   Would the distributer fire regardless of position?   How do I test ecu?   THank you for the help.

[NC RMP]

Glad it worked, was about to chime in on the fact that the transmission switch did not kill the coil, it kills the starter relay.  My Challenger would not crank once, was just dead at the starter.  I crossed the starter realy with the key on and bingo it fired.  Problem was the transmission safety switch.

[72rtchallenger]

OK guys, took 10 minutes at lunch with a meter.   Thanks for the jumper trick on the brown relay wire... it worked!

As far as voltage, I pu the negative on the battery and got 10v on both sides of the coil and 10v on both side of the resister.   Still no spark, however.   Any thoughts on my next step?   Would the distributer fire regardless of position?   How do I test ecu?   THank you for the help.

you should check the ballast to see if its good,,here is a thread on how to check it
http://www.cuda-challenger.com/cc/index.php?topic=52658.msg557614#msg557614

[jimynick]

Have you checked the obvious, like the cap, rotor and wires and plugs? Firing order? Pulled a wire and stuck in a plug and grounded it out to see if there was spark? 

[Jocigar]

THanks, i have done the plug test. 

Can I back track it to the coil to see if that is working? .... as I recall the main coil wire will spark once to ground every time the key is turned from the off position to the start position... correct? 

If that is the case, then I can move on to cap/rotor or wires.   

[Bullitt-]

If you get sparks from the coil wire to ground you have proved that power is getting to the ignition (you need more than 10V, at least 12v), the ballast resistor is good, the reluctor & pickup coil in the distributor are good,  the ECU is good & the coil is probably good. That only leaves the Cap & Rotor, Wires & Spark Plugs out.
    You need to crank the car with the ignition switch on.  Check your battery first to see if you have at least 12V if not charge it up, if you still can't get 12V to the ballast resistor there are issues with the wiring or ignition switch. You can temporarily bypass the wiring with a jumper wire from the battery to ballast resistor to test the ignition. 

[Jocigar]

Hi all, still going at it.

tested and got 10-11volts from all these places using battery terminal as ground;
both sides on the coil, from the coil wire out to inside of cap, both sides of resister, at the points. 
Battery is strong as it turns over fine.

also measured Resister @ ~1.1 ohms

still no spark out,  I tried putting meter at the end of the #1 wire while turning it over and never got voltage.  twisted the distributer to try and align rotor with TDC compression position of cyl 1

what am I missing?  what does the ecu do?  maybe I should order new cap and rotor just to try a cheap fix.  Car ran a decade ago when I parked it.

thanks again