cylinder no.3 misfire

[myold96]

my 2.3l sometimes misfires under load then i shift down,i've changed the plugs the wires are next followed by the coil pack and ign module because they are original from 96 and i was told the modules go bad after five years or so,should i go aftermarket(accell or ?) or go motorcraft?

 

[ianyboy]

If the motorcraft is known to blow after 5 years of loyal service, I'd go aftermarket IMO

 

[tomw]

The original design was subject to failure, enough that FoMoCo offered a payment under court order to those that had to replace the TFI module that was distributor mounted. The later models put the TFI on a heat sink mounted to the inner fender or firewall.

I would not replace a module unless it failed completely as I do not think that is the source of your problem. They generally work or they don't, being subject to heat related intermittent failures where a connector opens up when hot, and closes after it cools. In that case you would not have fire until it cooled down. Most do not have 'miss' type failures.

A spark plug will have its hardest time to fire when you are working the engine hard, such as climbing a hill in a higher gear without down shifting(manual or automatic). You might get slight 'bumpiness' or small hesitations in that case.
I would look more at the fuel delivery and metering system if you have a miss when you down-shift and increase rpms. Maybe check the MAF for cleanliness, or fuel pressure and delivery volume. When you bump the rpms, the fuel volume needed increases quickly as rpms increase and if the filter is gummed, or the pump or regulator a bit weak, you might have a miss due to lack of gas.
tom

 

[XLTsplash]

I would just replace the coil pack with a new Motorcraft part. I've been told the Accel coil packs don't last as long. The Motorcraft coil packs seem to be good my 97 2.3L still has the factory coil packs. The TFI modules do fail a lot. Its a good thing that Ford got rid of them and went to coil packs.