2002 Ford wont start

[djwallette]

I changed the motor in a 2002 Ford Explorer with one from a 2003 Ford Explorer. the motor is a 4.0 v6. I also changed the computer module (PCM) and now the Anti Theft Light is on and the vehicle will not start.

I found the Key pad Code also and I cannot fix the problem with this. I think the PCM needs to be reset

 

[2000StreetRod]

why the PCM?

Why did you change the PCM when you swapped the engine?
Your ignition key frequency codes are stored in the 2002 PCM. The 2003 PCM has other codes stored but not the ones for your keys.

 

[djwallette]

we changed it because the engine turned over but would not start we thought changing the PCM would help.

would it help if we changed the ignition switch and used the keys from the 2003 Explorer we got the PCM from?

 

[codyboy]

Hi. Just chimming in here. Did you have the opportunity to just diagnose the no starting with the original pcm? I'm not savvy about antilock systems, but shouldn't the power to starter be cut off therefore not turning over? so if the engine is turning over,there are so many other things that can cause a no start

 

[2000StreetRod]

use the 2002 PCM

I agree with codyboy that you should be using the 2002 PCM and determine why the engine doesn't start. There are multiple modules involved in the passive anti-theft system (PATS). Replacing the stock PCM with one from a 2003 model just complicated the situation. I suggest that you reinstall the stock PCM and then start troubleshooting.

Do you know that the 2003 engine is good? How long has it been since it last ran? The injectors can seize up and not spray if they sit for too long. Do you know if the engine was getting fuel? Do you know if there was spark? Did you check the compression? Which engine wiring harness did you use?

You will get lots of help from this forum and will learn a lot during the troubleshooting process.

 

[djwallette]

The 2003 engine last ran in April, 2014. We hit a deer on the highway and wrecked the front of the vehicle, we were still able to drive it, but it has been sitting since then; So the motor is good. We bought the 2002 Explorer a couple of weeks ago it had a bad motor; so we changed motors. But when we went to start it, it would not start. Were thinking the fuel injectors would not work.

If we put the old PCM (the 2002) back in what kind of trouble shooting should we perform?

Oh and we were going to try to take the ignition switch out of the 2003 Explorer and put it into the 2002 but we could not get it out of the 2003 one; too complicated.

 

[2000StreetRod]

PATS receiver

As I recall there is a module near the ignition switch that receives the signal from the ignition key. It communicates the frequency code/sequence to the PCM. Swapping the ignition switch so you could use the 2003 key would probably only enable the starter to crank. No different than using a non PATS key cut to fit the ignition switch.

Since the 2003 engine ran in April your injectors are probably still functional. Are they the same color as the injectors in the 2002? If so, they probably have the same flow rating and should work with the 2002 PCM.

Is the 2003 intake configuration identical to the 2002? I have no first hand experience with the 3rd generation Explorer but I know the intake manifolds were different for some year models.

Did you use the 2003 engine main wiring harness? If so, is it identical to the 2002 harness?

The basic requirements for an engine to run:
Fuel
Spark
Compression
timing

Those are the things to check for.

 

[2000StreetRod]

fuel injectors

According to Rock Auto the fuel injectors are the same for the 2002 and 2003 unless one is a California model and the other isn't.

 

[2000StreetRod]

intake manifold

According to an ebay seller the intake manifolds from 2001 thru 2003 are the same.

 

[codyboy]

So, how did you make out with your diagnosis? Just curious

 

[djwallette]

We had a Ford mechanic look at it and he had to change the wiring harness, there were 8 wires on the 2003 and 6 on the 2002; or something like that. that is what fixed it

 

[codyboy]

thanks for replying

Appreciated the reply.