What's the purpose of the ignition coil condenser?

I have a 1988 F-150 with a 351W V8. Engine came out of a 1995 Ford E-150. Its an electronic ignition system with one ignition coil, a distributor (no points), and a TFI Module, etc. Mounted next to the ignition coil is a can shaped condenser/capacitor that has a wire going to the igntion coil plug. What purpose does that condenser serve? What would the symptoms be if this went bad? If any. What does it do? I've heard and read several different things and I can't seem to find anything related to a system that doesn't have a points distributor. Mine doesn't have points, so why do I have a condenser?

That condenser is simply there to kill high voltage spikes that can feed back into the 12 volt harness. Voltage spikes can cause problems with the computer or radio noise.

Think about it. The coil is an inductor. When you apply a voltage to an inductor at first no current flows through it. But current builds up over time. When the voltage is cut the current will still try to flow through the inductor. If the current is pushed into an open circuit it creates a voltage spike which can damage either the points (arcing) or the electronic ignition components.

A condenser is a capacitor. A if you apply a current to a capacitor voltage will start at zero (or whatever voltage the capacitor was left at). But as current is fed into the capacitor it's voltage builds up.

The main thing this does is avoid a voltage spike. It's kind of like a roller coaster going down and then back up a track instead of going down and hitting a brick wall. What's even more interesting is that the coil/condenser is basically a "tank circuit" which can also force current back through the coil (like the roller coaster going down and then up one side but then rolling backwards). So this not only causes the magnetic field to colapse and induct current through the secondary winding, but also reverses the magnetic field, further pushing more current through the secondary winding and into the sparkplugs causing a hotter spark.

It is a radio suppressor
You get a horrid noise on the radio without it.

When the points (or the transistor replacing them) opens there's a VERY high voltage spike generated - this capacitor takes the top off it's othe points don't erode too quickly or the transistor doesn't fail immediately.

Since you don't have ignition points it must be a noise suppressor so you don't hear clicking on your radio.

First best answer to Ucan'thandlethetruth. I checked online ignition circuit diagrams and it is true: the capacitor ("condenser" goes back to Benjamin Franklin and the view of electricity as a fluid) is on the battery side of the coil. None of the diagrams show it on the negative side, which simply goes to the ignition module. That makes it a filter rather than the active component it is in Kettering ignitions. Expect radio noise, especially on weak stations on the AM band, if it is disconnected.