Help...PCM swap

[MM386]

History: '03, 136K miles. Recently started developing a hard knocking or what I think is miss-fire 35-45mph. Brought to Ford service. They say first thing is they cannot read my PCM. Please pay $700 for a new one before we can tell you it could be a $6 spark plug and what else to pay to fix problem. Luckily, I located a used PCM from right here. The two appear to be very similar, all the tags match up. The new PCM was recently converted back to the stock tune.

Current Problem: I did the swap, cleaned all connections, everything installed fine. There is power to the car. Turn key. NOTHING. I re-install a few times to make sure everything is seated correctly. Still nothing.

I reinstalled the old PCM. Car starts instantly.

Question: Am I missing some magic trick? Do I need to turn off the radio, lower the back window half way and do the hookie-pookie first?

Please you car geniuses... Any help is appreciated.

[dbc1965]

far from expert on marauder but I'm wondering could it be P.A.T.S IS NOT READING RIGHT WITH PCM.

[Blk Mamba]

Could it be that the key code is wrong, just wondering, I am far from a expert also.

[RoyLPita]

Did you program your keys to the new PCM?

[Dennis Reinhart]

History: '03, 136K miles. Recently started developing a hard knocking or what I think is miss-fire 35-45mph. Brought to Ford service. They say first thing is they cannot read my PCM. Please pay $700 for a new one before we can tell you it could be a $6 spark plug and what else to pay to fix problem. Luckily, I located a used PCM from right here. The two appear to be very similar, all the tags match up. The new PCM was recently converted back to the stock tune.

Current Problem: I did the swap, cleaned all connections, everything installed fine. There is power to the car. Turn key. NOTHING. I re-install a few times to make sure everything is seated correctly. Still nothing.

I reinstalled the old PCM. Car starts instantly.

Question: Am I missing some magic trick? Do I need to turn off the radio, lower the back window half way and do the hookie-pookie first?

Please you car geniuses... Any help is appreciated.


I have only seen one bad PCM, now did your old PCM have a chip in it, if it did this is why it could not be read, if you swaped PCM's you have to have Ford flash it to the Pats module and you have to have both keys or the car will not start, if you have a Xcall I can send you a tune with Pat's off and the car will start and run. You can then drive the car to the dealer and they can flash it back with Pats on.;)

[SpartaPerformance]

I agree the vehicle did not start because the module isn't programmed to your car, the PATS keys need to be adapted to that module.

[burt ragio]

What does PATS module stand for ?

[Dennis Reinhart]

What does PATS moduel stand for ?

Passive Anti theft System Chevrolet uses VATS Vehicle anti theft system most work with a resistance value embedded into the ignition key, on Fords you have to have two keys to re'set Pats, some after market alarms also use a key wrapped in a coil wire so it will see Pats and work with auto start.


New Ford Vehicles with PATS
For the 1999 model year, all Ford Motor Company vehicles equipped with the passive anti theft system will be using the PATS II system. The PATS II system was introduced on roughly half of the PATS equipped vehicles for the 1998 model year. The other half of the PATS equipped vehicles for the 1998 model year were equipped with the PATS I system. Many 2000 and later Ford Vehicles Use the E-PATS system, which uses an encrypted transponder in the key.
Hold on there... What is PATS, how does it work, and why is this important to me?
Good question. PATS is Ford Motor Company's passive anti theft system. In 1996 it started showing up on select models of Ford and Lincoln Mercury vehicles. The keys for these vehicles have a tiny radio frequency transponder embedded in the plastic Head.
http://www.1-800-pdq-keys.com/images/pats_key.gifWhen you attempt to start the vehicle, the on board computer sends out a RF signal that is picked up by the transponder in the key. The transponder then returns a unique RF signal to the vehicle's computer, giving it the ok for the vehicle to start and continue to run. This all happens in less than a second, and is completely transparent to the vehicle operator. It is a very effective system that does its job without the vehicle owner having to think about it, or modify his / her usual routine.
One thing the vehicle owner should think about is obtaining duplicate keys or replacing lost keys. No longer can you pick up an extra car key at the checkout stand of your favorite hardware store. Replacement keys must be originated on a new key blank that has an embedded transponder. The vehicles on board computer must be programmed to recognize the new key. This brings us to the "why is this important to me" part.
With PATS I, as long as you have at least one working key and can read the owners manual that came with the vehicle, you've got a good shot at programming your new key without additional assistance.
With PATS II, things become a little more difficult. Someone decided that two working keys be required for admittance to the programming show. On the surface, this is a good idea. It pretty much insures that only the owner of the vehicle will be making duplicate keys. The down side is that many vehicle owners don't think about making extra keys until they only have one, or even worse no keys!



If you own a vehicle equipped with the PATS II system and find yourself in this situation, you have a couple of choices.
Have your vehicle towed to the nearest Ford dealership. They will use their electronic programming equipment to reset the system and program in new keys.
Have an auto lock specialist who has electronic programming equipment and is qualified to use it come to your vehicle and do the same.
While option #2 is many times more convenient, neither solution is inexpensive.
Bottom line advice? If you own a PATS I equipped vehicle make sure that you always have at least two working keys. If you lose one of them, have a duplicate key made and programmed at once. PATS I equipped vehicles include the following.

[MMBLUE]

What does PATS module stand for ?


I'm with you WTH is PATS. Anywho, I sold the PCM to him and have a question " will any tune work to remove PATS or" :dunno:

[MMBLUE]

Thank you DR:bows:

[Dennis Reinhart]

I'm with you WTH is PATS. Anywho, I sold the PCM to him and have a question " will any tune work to remove PATS or" :dunno:


No the tune has to have the pats switch turned off which is normally not done, but easily can be by most competent tuners.

[MOTOWN]

and ill bet after all this, your problem is a bad coil(s), or cops, and may need a fresh set of plugs.

[MM386]

AHHHH! That must be the secret! I guess I will bring the whole mess to Ford to get the keys straightened out. I knew it had to be something silly like that. I really long for the days of fuel, fire, air to make a car go. All this computer junk makes it no fun.

Thanks Mauraderites for the ingeniousness!!

[Dennis Reinhart]

A bad cop will not kill a PCM it can cause a engine miss. And if the car has high miles I would probably change all of them, I would not go with after market coils. I would use the granateli boots and conductors, and good Ford Tech with a WDS or compatible scan tool can tell you exactly what coil or injector is the issue.

[MM386]

and ill bet after all this, your problem is a bad coil(s), or cops, and may need a fresh set of plugs.

That's exactly what I think. But you need a computer science engineering degree for your car to tell you that.

[TFB]

That's exactly what I think. But you need a computer science engineering degree for your car to tell you that.

Not really, just need a little ingenuity, the last place on earth I'm taking mine to is a dealer...

Without the ability to read codes, I'd just plan on replacing the plugs and carefully "read" each one removed... On any that doesn't appear normal, figure the coil and/or boot probably has a problem... Of course this assumes the hole(cylinder) is OK with good compression and the injector is firing... Really not much different than pre-'puter days when we would replace the plugs, check the wires distributor cap and rotor(and if old enough service the points and condenser)...

[Dennis Reinhart]

I agree the last place I want to go is the dealer, but I have a good relationship with several dealers, Russel Wright AKA Ford wrench is a very good tech as well as a good service adviser, and is as honest as the day is long. There are times when I use him as I said what could take hours and hours of trouble shooting, can be solved in minutes with a good technician and a Ford IDS. Pat spent about a thousand dollars on his car, by some one guessing and a tech that worked on local police cars found the trouble with a IDS, so again some times it is better if you know a good tech, if not find one buy him lunch it is far worth it, I have a old NGS it helps a lot but the tool of choice is the IDS. The IDS can dtermine compresion and bad injector or coils it can check every module in Ford cars.

[MOTOWN]

A bad cop will not kill a PCM it can cause a engine miss. And if the car has high miles I would probably change all of them, I would not go with after market coils. I would use the granateli boots and conductors, and good Ford Tech with a WDS or compatible scan tool can tell you exactly what coil or injector is the issue.

i agree, but your assuming the dealer was correct in saying the pcm is bad, or unable to be read!, ive worked at three different dealers, and all techs are far from equal, or competent for that matter.

[Dennis Reinhart]

i agree, but your assuming the dealer was correct in saying the pcm is bad, or unable to be read!, ive worked at three different dealers, and all techs are far from equal, or competent for that matter.

I am not sure on that, again if the car had a chip in the PCM the scan tool will not read it, if you loose 12V to the OBD2 connector it will not read the ECM

[MOTOWN]

in the meantime ill be looking forward to that interesting cold air intake!