Hi, Can someone help me with 2000 V6 mustang?

Check coil pack RD/LB wire

Note: not a good idea to double post in tech and talk. This is obviously a TECH request.

Confirm the year, make, and model of the donor car. The other post stated the donor was a 1999. However, it did not say it was a V6 or V8.

Note: the differences between a 1999 MY and 2000 MY are very small.

Confirm EXACTLY which parts were swapped. Was there any damage to the electrical harness?

If given pinpoint electrical tests, can you do them and post the results? Do you have a VOM meter? Do you have a noid light?

Start by looking at the attached diagram. The diagram is from the 03 MY, but it should be close enough for this purpose. Note that if the coil-pack RD/LB wire back to the PCM were bad/open, this would cause the reported symptom. Inspect the connectors at the coil pack and PCM. Look for loose/bent pins or chaffed/burnt wires. Anything that could disrupt the flow of electricty from the coil to the PCM.

Recommend that you do not drive with two cylinders missing. The large amount of fuel in the exhaust will damage the cats.

Gave you several good suggestions already. Now it is time to do some troubleshooting. Have you reviewed the wiring diagram? Have you inspected the wiring harnes as requested?

Note, if you think this is PCM programming, then the battle is lost. Hint, if it were programming, then the car would not start. The fact that it starts and runs (although poorly) indicates that most everything is sound.

Hint: many aftermarket security systems work by breaking the circuit to the coil. This problem could easy be left over from the aftermarket security system.

But since you have checked EVERYTHING, then there is no hope.

On the otherhand, should you decide to go back and find the open in the RD/LB coil circuit, you could be driving it instead of talking about it.

Start by grounding (key on) the RD/LB wire at the coil while testing for spark to the #3 & #4 cylinders. Don't hold the ground on for long periods of time or you will burn up the coil pack. If the coil pack is good, you will get a spark each time the RD/LB wire is grounded.

Now that we know the coil pack is good, then we need to test the circuit back to the PCM. To confirm the noid light, test between WH/LB and the DB/LG wire (#1 & #5 cylinders). Since these are known working, this has to flash or the test light is no good.

Put a test light (noid light) between the coil pack WH/LB and RD/LB wire. Crank the motor. The light should flash each time the PCM requests spark. If not, there is an open in the RD/LB circuit.

Sooooo. should you confirm there is an open on the RD/LG wire, start tracing the harness back to the PCM.

At the risk of sounding rude, the reply leaves me with more questions than answers.

Why are you asking questions about a V8 PCM? The earlier posts stated the donor car was a 1999 V6 automatic. A PCM from a V8 will NOT directly work in a V6. The PCM must be calibrated for the motor and transmission.


No information about the resusts of the tests has been included. No information about the after market security system has been included.

What was the Ohm reading of the RD/LB circuit from the coil to PCM?

What is the Ohm reading of the RD/LB circuit to ground (coil disconnected/key-off)?

What is the voltage reading to ground of the coil RD/LB circuit (coil connector disconnected, key on, engine off)?

Soooo. If the wires are good, the coil is good, and all connections are good, and the PCM calibration is correct, then the only item left is a bad coil driver in the PCM.


>>From Ford service CD.
P0351 Through P0360 - Ignition Coil A through J Primary/ Secondary Circuit Malfunction

Each ignition primary circuit is continuously monitored. The test fails when the PCM does not receive a valid IDM pulse signal from the ignition module (integrated in PCM).

Open or short in Ignition START/RUN circuit
Open coil driver circuit in harness
Coil driver circuit shorted to ground
Damaged coil
Damaged PCM
Coil driver circuit shorted to PWR

musfan said:

Whats the difference between Ecu and Pcm?
I am taking about V6 ONLy. maybe typo before.
also where are they located? ( Ecu and Pcm)
I will post the reading for the results later because i forgot to record them. i have to redo them again.

Click to expand...

ECU and PCM are the same thing. Interchangeable terms.

The PCM is located on the left hand side kick panel (confused as previous post said that the PCM was swapped with donor unit).

Did you perform the other tests to confirm the coil function. What about tests for stray voltage and grounds on the coil circuit?

Musfan, as long as the donor vehicle was not a V8 you do not have to reprogram the PCM. If the donar was a v8 you will have several problems & will have to reflash the PCM., or get another v6 PCM from automatic trans vehicle.

Assuming you have a donor v6 PCM then the problem looks to be in the primary circuit coil driver , for the #3#4 coils (which fire simultaneously from the same driver circuit). Follow the directions above and use a test light to confirm coil driver pulses. No pulses= bad pcm or shorted/ open harness wire.

Good Luck!

Aeroman.