1990 f150 351w. Was chasing a no spark issue, wrongfully fired the parts cannon without diagnosis, replaced icm, coil, ignition switch, distributor, ecu. I now have this much spark from coil and distributor cap(see videos below) and still can’t get it to do anything at all; even with ether sprayed in the intake. At a loss of what to do next.

 

So you have spark, its just weak.
Measure resistance of the spark plug wires. Make sure all connections are clean and tight. Test the coil and the PIP circuit. Just because a part is new does not mean that it is good.

 

I would be very suspicious of any aftermarket ignition modules.

 

Use an actual spark tester
You might not be able to see 40KV The spark tester can be adjusted to let you see 40 or 20KV
The big three... Spark, fuel and compression.. You got those? Right? Better check all 3 one more time
Use a fuel pressure gauge
Chek the spark plugs for being wet or fuel fouled
Use a noid light tester for the injector signal test from the processor (or make your own out of a 194 bulb)

 

thanks foe the response. I have spark from coil. I tried starting with starter fluid and and stillnothing. The spark from plugs wires to plugs seems weak in my opinion, maybe not.

 

First video is spark from coil, second video shows spark from plug wires to spark plugs.

 

I'd check to see if the rotor in the distributor has been shorting out
Look for carbon tracks on the inside, where the shaft goes up into the rotor
Look to see if the center ball in the cap is loose
You have tried starting it using flood clear?

 

Thanks for the reply my friend, the distributor is new, inside the cap and around rotor still look clean. How would I tell if the rotor is shorting, by carbon tracks on the inside? I’ll double check the center ball is tight. I have tried several times to start with spraying starting fluid directly into the butterfly valve and nothing, not even a backfire.

 

Yes, carbon tracks inside where the center post meets the rotor
Most of the newer caps do not have the center ball that gets loose
Instead, they have a spring loaded button that does not get loose and negate spark
Because you replaced the processor, might want to try to start it with the spout plug removed
Personally, I would start over with the "rough time"
Means pull #1 spark plug and bring that piston up on compression and verify the rotor is pointing to 1
If it will not hit on ether, either the compression is weak or the timing is way off
Fuel, spark and compression, you're missing one
When I get pissed, I verify I can start myself on fire using the gas in the vehicle
Then verify compression
Then go back to spark diagnosis
You have spark although weak after going through the secondary ignition parts (cap, rotor and wires)
Double check the base or rough time by pulling the #1 spark plug
Double check the compression while the spark plug iis out, and use a gauge to get a number
80 lbs will not start a motor but 100 will
At 80 lbs you should get a rumble and an almost start condition. Fire , bang boom but no start

 

I paid someone to change the distributor and wasn’t present best I could tell base timing was off as rotor was pointed toward #5 when on compression stroke. Sunday I followed procedure while on compression stroke and turning the motor over by hand to tdc, placing the distributor in again being careful to aim the rotor at #1. 99.9% positive I done it all correctly. I will verify again tomorrow by checking rotor direction when on compression stroke. I will also check compression while I’m at it and follow up here.

Thanks for the help, at this point strongly considering pushing this thing over the hill and calling it done.