[amy1]

In the conversion process of my 92' 4.3 Vortec in an S-10 Blazer I have come to a screeching halt... It has no spark! I have installed a #2111 Edlebrock intake, #1404 carburator, Mallory bypass regulator and finally the problem a 1985 Astrovan HEI distributor. The HEI has a connector with 3 wires (Brown, Black and Tan) which I was told plugs into the back plug-in on the cap. I also have a hot wire run to the Batt plug-in in the front of the cap. I have no spark so therefore have to be missing something.... but what!!!! Please help!

[bprumos]

this probably isnt going to help you all that much since you probably already checked this stuff... but little things can be monsters. i would check to make sure the module is getting key on power, and power when the the key is on start also. check grounds and wire continuity as well. also check hard parts such as coil and distributor to make sure their all in order. i know just last week i couldnt figure out why i wasnt getting spark, until i realized i leaned on the distributor cap and cocked it to the side so it wasnt contacting the center terminal... only way i found out was that i leaned on it again and it moved back into place ha wish i could be of more help but i dont really know that system very well.

[LATECH]

No spark can be several things. You should check for 12 volts at the big pink Or red wire that you have to the distributor cap. If you have power then you will have to start checking internal components.
The ignition module can be tested at napa, ( they used to be able to,you should call) The pickup coil and the ignition coil you can test with a volt ohm meter.
I have also seen the rotor itself have a burn hole in it where as the spark grounds itself out before it has a chance to get to the cap or wires. Look at the rotor where the carbon contact from the ignition coil touches . underneath should not look all black and discolored.You should look real close. If you cant tell and it doesnt look pretty decent just put one on and try it.they arent real expensiveand they are prone to failure.

Pickup coil resistance should be between 500 and 1200 ohms
Coil primary should be about 1 ohm but not zero or infinite
Secondary should be between 5000 and 20,000 ohms but also no zero or infinite. Good luck

[amy1]

Thanks for the reply. I have a brand new distributor, cap, rotor, coil.... I have converted from a CPI (spider system) to a carb. I have checked everything over and think the problem lies with the ECM because many sensors are eliminated or not hooked up. Specifically the old computerized distributor wires bother me. I have only a hot wire to the HEI distributor there has to be something telling the ECM to not fire. Please help!

[LATECH]

If you have the distributor with the coil in cap...and you have eliminated the fuel injectors (spider,correct) then it should run.
Are you sure there is still no spark?The computer wont matter if your distributor has a vacuum chamber(diaphram) and advance weights inside.
Wich distributor do you have?very important.Maybe you can post a pic

[joe_padavano]

Since you have eliminated the EFI and the computer controlled distributor, the ECU should have nothing to do with this. Does the vehicle have a VATS antitheft system? If you are using the stock wire to power the HEI, that might be the problem.

[amy1]

Originally Posted by latech

If you have the distributor with the coil in cap...and you have eliminated the fuel injectors (spider,correct) then it should run.
Are you sure there is still no spark?The computer wont matter if your distributor has a vacuum chamber(diaphram) and advance weights inside.
Wich distributor do you have?very important.Maybe you can post a pic

I have an HEI from an 85' Astrovan with the vacum pod.

[LATECH]

well then it should have spark and should run.Did you check everything in the distributor to make sure it is OK.( Just because it is new dont mean nothing)
With that distributor and a carb the ecm does nothing here. Forget about it.
as long as there is power to the distributor it should spark. Do you have sufficient ground wiring for the engine?

[AJNeville]

I just pulled an 85 Astro Van 4.3. (carbureator and HEI) I was worried about the wiring because I plan to install the engine in another vehicle. When I unplugged the 4 wire connector going to the distributor the engine died. It obviously won't run without doing something to these wires. I am hoping a jumper between the correct two will allow the engine to run, but I haven't figured it out yet either.

[LATECH]

Jump wire the A connection to the C connection at the 4 pin connector on the distributor. That will make it run without having a computer hooked to it.