so i been trynna get my 87 ta running for a few weeks now. i have no spark at all, however there is power going to the coil, the coil is new the plugs, wires, cap and rotor are new along with the ignition module under the cap. i am thinkin the electronic spark contol module on the firewall is bad, but hell so now i wonder if i install my crane cams hi6 does it like bypass that or does that have to be working for my crane box to work?

 

Module on the firewall is called ESC - Electronic spark control module and it is used in conjunction with Knock Sensor KS. ESC module detects occurrence of knock, but it has nothing to do with spark generation. Leave ESC alone until you figure out no spark condition.

There are several reasons why you may have no spark. Assuming that all ignition components (coil, two wire harness, HV lead, rotor, cap, ICM module, 12 volt is present at B+) are good and there are no bad wires one of the most common causes of no spark is reluctor coil is bad. A two pin connector plugs into back side of the ICM inside dizzy. To check - disconnect from ICM and measure coil resistance with DVM - it should read 500 to 1500 Ohms. Anything else is considered bad.

Before you hack your ignition system by installing that HI6 you need to having it working as it was designed first.

//RF

 

the 2 wire leads from the reluctor coil is reading around 829 in resistance. should i be checking it for voltage? i dont know if i need to mention that i have a small cap external coil disty and it is factory. so what should i be checking now? o yea those wires from the reluctor have corrosion on them, and the grey connector to my coil is a POS its just 2 prongs sticking out no hold down clips or anything, maybe ill make a trip to the pick and pull and get some pig tails.

 

830 Ohms is about right for reluctor coil, and if you attempt to measure voltage output from stationary dizzy you'll get 0 volt output. GM dizzy uses rotating magnets positioned on the dizzy shaft to induce current flow in the reluctor coil. ICM detects when induced current changes direction to produce a DRP signal which is input signal to ECM indicating dizzy relative shaft position. Thats your basic operation of this system.

It is very common for reluctor coil connector to break over years of service and crud to form therewith. Do not attempt to attach big tails to reluctor coil - the wire size is just too small!


Note that connector reversal may cause no spark condition...

Question: Do you get spark at coil output??? Do you have + 12 volts when cranking on the main +B (pink wire) feeding coil??

//RF

 

i wont be able to test anymore until tomorrow. the grey connector on the coil had a broken pin in it that finally came out (in my brand new coil) so ill be visitin the pick and pull to get new connectors. also forgot to mention that car ran when i put the starter in it ran like crap but it started and died, then started and died, and if u hit the gas it died, then after like 4 starts it hasnt started since. i do have power at the pink wire of the coil with the key on, i havnt tested it while cranking yet. and i dont have a connector coming from my reluctor coil it just 2 wires with metal teminals on them that plug into the ICM. could u tell me which way they should be hooked up? when i changed the ICM i just did them one by one so they wouldnt be mixed up. however the car came from a complete and total lier and retard that swore it only needed a starter which it didnt need it was a melted battery cable. o **** i should mention that the battery cable melted to the long tube headers and grounded the battery out and blew it up so maybe something got screwd up

 

'enstein If you are going to pick your JY it would be handy if you pick up a spare ignition coil and ICM along with two wire harness between dizzy and coil. Look for Astro vans, full size trucks and F- bodies for these goodies. Since you have a basket project and god only knows how badly PO hack on it you need to cleanup screw-ups in a systematicly. Starter circuit has very little in common with ignition system except that the main +B ignition non switched circuit originates from main starter stud. I think that you may find that after replacing broken connector you just may get spark. Reluctor coil connection uses white and green wire - I'll have to double check which terminal on ICM they plug into. //RF