93 Taurus - Starting issue

Bad ignition swtich?

Bob

Really? Bad ignition switch can cause fuel pump and fan issues, and check engine light malfunction? I guess that is one thing to check, I will look into that one today and get back.

If you have a lack of power problem, the only way to tell is get the shop manuals and trace every circuit back to its source and determine what has power and what does not.

You may also have a wire harness that has chaffed and been cut somewhere. I junked a taurus once and the harness on the drivers side over the end of the engine was chaffed and cut in places.

The fan and fuel pump are also controlled by the CCRM relay module that is located over the radiator. Sometimes these modules can develop bad connections internally and cause some problems.

Bob

Bob, thanks for re-plies, the relay module on the radiator is on its 4th replacement, seems to help for 1-2 days, but then a weather shift - again humidity seemed to be a factor. Now, I have nothing. no indication the fuel pump is responsive, fan no longer comes on. ignition switch seems to be ok, although I still cannot get a "check engine light" to perform MIL diagnostics, Fuel Pump testing is not happening either.

Question: if the Fuel Pump IS bad, shouldn't I be able to get a reading off the of the MIL diagnostic checks? or at least an indication of "no fuel"?

Again, Appreciate the help.

That old of pre OBD2 diagnostics doesn't tell you much. You could hot wire the pump and then get a fuel pressure gauge and put it on the fuel rail test port and check pressure. Keep in mind there is a roll over switch in the trunk i believe that could also cut power to the pump if its intermittent. Or even a bad connection on the in tank pump. Any way you look at it, you need to see where you have power and where you don't when this happens

Bob

Everything points to the CCRM, Did some investigating on a few sights today, as well as troubleshooting on the vehicle. All symptoms point to the module.

thanks again