1990 Ford E-150 not getting spark

It's generally a bad idea to "test" an alternator by removing the battery cables, since that's a quick way to fry what's being tested. Your alternator may now be dead. Vehicles of that vintage still had the TFI module (mounted on distributor or near radiator) that could go bad at any time and cause a "no spark" condition.

(T)hick (F)ilm (I)gnition.

No. It is the ignition control module.

Look very closely at both ends of the coil wire. Very common to find rot and corrosion. Check for 12 volts at the small red wire at the ignition coil with the key on. Check for pulsing voltage at the small green wire at the ignition coil while cranking engine. Check for 5 volts at the yellow wire at the coolant sensor. Check to see that the ignition rotor actually turns when cranking the engine.

Do you hear the fuel pump run - about 2 seconds, then off- and see check engine light on key-on?

If see that, and no spark you probably blew the ignition module but it may have been ready to go anyway.

It's mounted on the side of the distributor, or maybe remote - follow harness wires from dist base.

It's easiest to get a $5 special tool any autopart store to remove it, the heat-sink grease between it and mount should be fresh, not caky.. if caky, it was going to fail.

Autozone.com has component locations, by the way

-- Yeh, I'm a Krusty old Geezer, putting up with my 'smartass' is the price you pay..DEAL with it!

Hard to tell what you fried when you did the ill-advised alternator test (pulled battery cables with engine running), maybe took out the ignition (RUN) side starter relay or the ignition switch, or the 500-ohm resistor on the charging idiot light. Best bet is to get the engine trouble codes read and actually check fuel pressure with a gauge. You also may want to go to one of the many Ford Truck forums and make an enquiry on there.

Susan, start here

has the simple way to read the codes. You cna try all three phases, but with a cold engine the Key On Engine Off test will give you the stored codes. I am getting better at these, email me if you need some insight. George

Gee, the truck is 17 or 18 years old. I would expect a few problems every now and then.

Jeff

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