ok; here are today's top contenders!
In the near corner, we have the TFI Module! (& or the hall effect sensor in the distributor); an excerpt from a TFI Law Suit article:
"...A TFI module can fail on an intermittent basis when hot, then function again when the engine cools, without leaving a trace of physical evidence that the TFI module had failed.
Rather than bearing the expense of moving the TFI module to a cooler location away from the engine...Ford decided to employ a less costly solution: to leave the module on the distributor, but make it last long enough to function during the warranty period, thereby forcing consumers to bear the cost of post-warranty failures that Ford knew would continue to occur in large numbers. As a result, over 13 million replacement TFI modules (which are designed to last for the life of the vehicle without maintenance or repair) have been sold to consumers at a cost of nearly $2 billion..."
The following vehicles have distributor-mounted TFI modules
1984-90 Bronco (4.9L)
1984-91 Bronco (5.0L)
1984-85 & 1988-91 Bronco (5.8L)
source is http://www.autosafety.org/article.ph...=&did=362...if
it's this you can be reimbursed!
more, TFI Testing:
TFI & Hall Effect Sensor Testing (for stangs, but similar) by P B at onr.com
in da other corner is the fuel pump... but it's over-weight, sloppy, and shoulda been a contender years ago; so how about a fuel press test at the fuel rail (schareder valve)