Ford Mustang: 1988 Ford Mustang Fuel Problems

Check your EEC power relay too. It looks just like your fuel pump relay but is under the
passenger side kick panel. The EEC relay powers up the inertia switch which then powers
the fuel pump relay. HTH StuK




"Lori" <ca> wrote in message news:accesscomm.ca... 

Stuart&Janet opined in news:RNS4b.339$golden.net:
 

Well... not actually. The EEC relay powers up the eec, Which then can turn
various other relays/solenoids on and off.

Including the Fuel pump relay. The inertia switch is only an interruptor in
the line from the relay contact back to the fuel pump.

BUT

Stu's right about the EEC relay.. common failure and probably has
corrosion/rust in it. WHen you install the new one, make sure the base is
DOWN.


While you're down there, make sure the wiring ground lug (to metal just below
the EEC) is making good contact and tight.

Actually it applies + voltage to the inertia switch directly as well as the EEC then to
the FP relay . The EEC actually completes the circuit after the fuel pump relay by
grounding it, which would make your statement regarding grounding the EEC dead on.

Sometimes just giving the relay a kick gets em going again, BUT percussive maintenance is
not a good long term strategy IMO.

BTW. I'm cheating. I have the EVTM but I've been down this road myself on a few cars.
StuK



"Backyard Mechanic" <com> wrote in message
news:168.3.44... 

Stuart&Janet opined in news:rvT4b.347$golden.net:


 

Okay.. on an 88?

The 87 has no such connection according to Mitchell which is pretty accurate.

BUT I ALSO have a 93 EVTM

And I see what you mean, but it isnt "powering up" the inertia switch, a
switch is a switch.

Note that the power to the pump is supplied by the FPR... I'm looking at the
93-94 on the factory CD ROm and there is indeed a wire from the connection
BETWEEN the FPR output and the supply side of the inertia switch. That is a
"sense wire"..

The PCM internal circuit would SUPPLY 12volt from a high resistance on that
pin. If the inertia switch or Fuel pump were open, then the PCM would see a
positve voltage after the Fuel Pump Cycle finished. NOrmally after the
cycle, the lead would be LOW.

If PCM has turned on the relay and the lead in question read LOW or NO
voltage, it would flag a fault in the CCRM FP relay

That is how it can sense a Fuel Pump Circuit failure

AFAIK, that code, #95 or 96, is not relevant to an 88.

So YOu are right.. but I'm righter!

Ooops. Clarification!