We're To Get A Rebuilt A9l Computer?

We're as in "we are", or where as in " where" ?

Check the relay and the fuel inertia switch in the trunk. If those are good then you can look in the check list to see how to jumper the fuel pump from the diagnostic port. No fuel after that would mean bad pump

Bob91vert said:

We're would I get one at? Can you get em rebuilt?

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How did you determine that you need a replacement computer? They seldom fail, usually it is sensors and wiring that cause problems.

Bob91vert said:

Like I said above. I was told it needed one from the shop the original owner took the car to. That's where I met the owner.

So, yesterday we went thru it. I have spark and 43 lbs of fuel pressure. I have power to the injectors red wire. But the noid light showed no injector pulse.

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Possible PIP sensor failure....

The PIP is a Hall Effect magnetic sensor that triggers the TFI and injectors. There is a shutter wheel alternately covers and uncovers a fixed magnet as it rotates. The change in the magnetic field triggers the sensor. They are often heat sensitive, increasing the failure rate as the temperature increases.

PIP Sensor functionality, testing and replacement:
The PIP is a Hall Effect magnetic sensor that triggers the TFI and injectors. There is a shutter wheel alternately covers and uncovers a fixed magnet as it rotates. The change in the magnetic field triggers the sensor. A failing PIP sensor will often set code 14 in the computer. They are often heat sensitive, increasing the failure rate as the temperature increases.

Some simple checks to do before replacing the PIP sensor or distributor:
You will need a Multimeter or DVM with good batteries: test or replace them before you get started.. You may also need some extra 16-18 gauge wire to extend the length of the meter’s test leads.
Visual check first: look for chaffed or damaged wiring and loose connector pins in the TFI harness connector.
Check the IDM wiring – dark green/yellow wire from the TFI module to pin 4 on the computer. There is a 22K Ohm resistor in the wiring between the TFI and the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 22,000 ohms +/- 10%.
Check the PIP wiring - dark blue from the TFI module to pin 56 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
Check the SPOUT wiring – yellow/lt green from the TFI module to pin 36 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
Check the black/orange wire from the TFI module to pin 16 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
Check the red/green wire; it should have a steady 12-13 volts with the ignition switch on and the engine not running.
Check the red/blue wire; it should have a steady 12-13 volts with the ignition switch in Start and the engine not running. Watch out for the fan blades when you do this test, since the engine will be cranking.
If you do not find any chaffed or broken wires, high resistance connections or loose pins in the wiring harness, replace the PIP sensor or the distributor.

The PIP sensor is mounted in the bottom of the distributor under the shutter wheel. In stock Ford distributors, you have to press the gear off the distributor shaft to get access to it to replace it. Most guys just end up replacing the distributor with a reman unit for about $75 exchange

PIP problems & diagnostic info
Spark with the SPOUT out, but not with the SPOUT in suggests a PIP problem. The PIP signal level needs to be above 6.5 volts to trigger the computer, but only needs to be 5.75 volts to trigger the TFI module. Hence with a weak PIP signal, and the SPOUT out, you could get spark but no injector pulse. You will need an oscilloscope or graphing DVM to measure the output voltage since it is not a straight DC voltage.

See http://www.wellsmfgcorp.com/pdf/counterp_v8_i2_2004.pdf and http://www.wellsmfgcorp.com/pdf/counterp_v8_i3_2004.pdf for verification of this little detail from Wells, a manufacturer of TFI modules and ignition system products.

Bob91vert said:

Like I said above. I was told it needed one from the shop the original owner took the car to. That's where I met the owner.

So, yesterday we went thru it. I have spark and 43 lbs of fuel pressure. I have power to the injectors red wire. But the noid light showed no injector pulse.

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Make sure the computer is powering up first. With the key on, check for 5v at the tps orange wire. And make sure you have 12v at one of the injectors red wires.

Bob91vert said:

I have 12 volts at the injector red wire.
Shows 1 volt at tps Orange wire.

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That tells me the ECM relay is working. The 1v at the TPS is not good. I didn't think about it much. But assuming the Fuel Pump wiring is stock, and the fact that you get fuel pressure tells me the ECM is actually working. But that doesn't mean it is fully functional. The ECM can fail in many ways and still operate to an extent.

You should show 5v at the TPS orange wire when tested to a body ground or the black wire on the TPS. What did you use for the ground when testing the orange wire?

Bob91vert said:

I went to the body and a couple other places. I've had 2 very seasoned diagnostic guys look at it. Both had all test equipment and did not need the checklist. They were right on in what the checklist says to do. Both say the comp. has a short and needs to be replaced or rebuilt. I'm still hesitant to just buy a computer based on what I read here.

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Well, It looks like they may be right. You have to understand that these computers are getting old. If you work on alot of these cars, you will see that computer failure is actually getting pretty common. But like I said, you can have a computer fail, and still run the car. They fail in many ways.

What do you have at the STI?