94 X dies, now won't run.

[Matt Fisher]

I'm going to try and include as much info as possible, so this may be a little long. Thanks in advance for your suggestions.

94 X 170K. For about a year now, it's always had the occasional need to crank on the starter more than once, or for a bit longer than I'd like. In the last 2 weeks, it's gotten worse, and sometimes will cut out while driving down the road. 3 days ago it took 20 minutes for it to start, has gotten progressively worse, and as of this morning, it's DOA.

However, I haven't ignored the issue, and have replaced the following items:

-New plugs/wires 6 months ago. Today I tested for spark by removing the plug wire off #1, putting a spare plug in there, laying it against the fender, and cranking the key. Sparks like mad. Pulling the actual #1 plug shows it to be black and sooty (keep reading for ideas as to why it's not light brown), but it's not wet.
-Used ECM 5 months ago. The last one had a stroke and caused the CEL to stay on. My CEL is NOT on at this time, and has not come on (except during cranking) since the new/used ECM was installed. New 02 sensors then too.
-3 days ago when it took 20 minutes to get it started, I took it into a local shop. It was running horribly, and wouldn't hardly idle. They diagnosed a bad MAF (said that it was running unbelieveably rich), and replaced it with a new one. It ran better, but did cut out on the freeway a few times. I did notice that the hard starting issue was most prevalent upon shutting the vehicle down after only 2-3 miles of low-speed city driving; not totally warmed up.
-New fuel pump/filter 2 months ago. Today I became convinced that the pump was the issue, and swapped it out again- to no avail. Also today after pulling the codes, I also replaced the crank sensor- still not starting. When the shop had the rig 3 days ago, they tested for fuel pressure and said it was fine, I thought it was possibly intermittently bad pump. Fuel pump relay clicks over just fine, I even tried jumping it and leaving it on while cranking it over.
-The KOEO codes that came up are: 539, 21 and in memory- 542 & 211. Obviously the vehicle is cold, and no KOER could be checked.
-The fuel pressure regulator holds vacuum. Depressing the schrader valve does result in fuel spraying out.
-New TPS 5 months ago.

When I first try cranking it over, it acts a little bit like it wants to start. Continuing to crank on it does nothing. In order to get it to run for 1-2 seconds, I have to wait a couple minutes before cranking it over again. What convinced me to swap out the 2 month old fuel pump even though the shop said it was fine was getting it to run for 5-6 seconds on Engine Start (ether). I sprayed it down the intake while my neighbor cranked on the key- it did run for a few moments. This only really worked once, and I've used up 3/4 of the can today- this may also explain the black spark plug I mentioned above. An occasional mild backfire does occur. This does result in blowing the hoses off the vacuum tree, but I re-install them. Yesterday I did happen to listen for vacuum leaks, and did not hear one.

Excepting the occasional refusal to start, and the odd/intermittent cutting out on the freeway, it's been business as usual. Not much power, and consistantly lousy fuel mileage (13-16). Typical 4.0 OHV.

I really don't want to continue throwing parts at this thing (can't afford to for that matter), but need it for work. Any ideas are greatly appreciated.

 

[MrShorty]

KOEO 539 indicates that the AC was on during the test.
Shouldn't be getting a KOEO 21. should be getting three digit codes. Could this have been a KOEO 121?
CM 542 without an accompanying KOEO code suggests an intermittent fault in the fuel pump circuit. When the engine stalls or won't start, is the fuel pump coming on. I must emphasize that the code list you've reported indicates that this is an intermittent fault or an old fault. 1st step might be to clear CM and test drive and see if this code comes back in conjunction with the next incident or not.
CM 211 indicates a fault in the profile ignition pickup signal. I'm not familiar with how your '94 is set up, but I think this is generated by the crankshaft position sensor and passed to the PCM via the ICM. Does your '94 have a CKP? 1st step in diagnosing this one is to see if it is consistent. Clear CM and test drive and see if the CM 211 comes back immediately. If not, does it come back in conjunction with the next incident?

 

[Matt Fisher]

It does have a crank position sensor, replaced it with a new one yesterday.

Today I reset everything, tried KOEO- only 111 showed up.
Then tried to start it, and just like always, it "wants" to run the first time I crank it over, but dies within a few revolutions. After that the motor spins from the starter motor, but there's no detectable "activity". If I wait 5 minutes and try again, the same thing happens.
After cranking on the starter for about 20 seconds, I tried the KOEO again- to be rewarded with 226.

According to my little book this means "Electronic Distributorless Ignition System (EDIS) problem- Ignition Diagnostic Monitor (IDM) signal not received".

Does this mean the Ignition Control Module (aka Thick Film Ignition) has gone kaput?

 

[MadExplorer93]

It does have a crank position sensor, replaced it with a new one yesterday.

Today I reset everything, tried KOEO- only 111 showed up.
Then tried to start it, and just like always, it "wants" to run the first time I crank it over, but dies within a few revolutions. After that the motor spins from the starter motor, but there's no detectable "activity". If I wait 5 minutes and try again, the same thing happens.
After cranking on the starter for about 20 seconds, I tried the KOEO again- to be rewarded with 226.

According to my little book this means "Electronic Distributorless Ignition System (EDIS) problem- Ignition Diagnostic Monitor (IDM) signal not received".

Does this mean the Ignition Control Module (aka Thick Film Ignition) has gone kaput?

IDM NO it is the IDM(injector driver module), but check the wiring for it see it anything is corroded before buying a new one, opps it maybe in the PCM the computer itself.

If the engine is cranking and cranking and no start happens then it is due to no spark or ignition managment or fuel issue.

You changed almost everything that can be fuel related and you changed the plugs and wires and crank sensor.

 

[MadExplorer93]

Here is a quote (BELOW) from an article posted in this very FORUM:

http://64.233.167.104/search?q=cach...ford+explorer+module&hl=en&ct=clnk&cd=3&gl=ca


"PCM - Powertrain Control Module - the computer

EDIS - Electronic Distributorless Ignition System - basically an Ignition Control Module for Distributorless Ignition. 12-pin connector.

IDM - Ignition Diagnostic Monitor - is in the PCM

Pin# 4 on the PCM connector has a Tan/Yellow (T/Y) wire. Pin# 2 on the EDIS connector should also be a T/Y wire. by doing an Ohms check between the two connectors you are making sure that wire is in good condition.

Pin# 4 on the PCM connector has a Tan/Yellow (T/Y) wire. Pins 40 and 60 are BK/LG (Black/Light Green). Pin 46 is BK/W (Black/White). by doing an Ohms check between Pin 4 and Pin 40, Pin 4 and Pin 60, and Pin 4 and Pin 46 you check to make sure there is not a short between those wires.

hope this helped clarify some. let me know if you need more clarification."


-------------------------------------

The other thing it can be is the ICM which is the Ignition Control Module, that module interacts with the IDM and PCM signals. So check all wires for the ICM then go from there and if you suspect it is the ICM well then replace it.

 

[Matt Fisher]

This is looking more like a PCM issue.

I just tried 2 different EDIS modules. This is the module on the radiator support, in front of the battery. Still not starting. No visible corrosion. At least it's on the passenger side and not covered in a thin film of power steering fluid from a leaky pump on the driver's side. must think positive thoughts, must think positive thoughts...

Checked for continuity between 4 and 40/60/46 on the PCM harness. No continuity, and 60/46 have no connector in them.

With my cheapie meter set on the 200 scale for ohms, it registers 6.8 when checking between pin 4 of the PCM and pin 2 of the EDIS. Should there be any continuity between PCM4 and ground, or EDIS2 and ground?


Here's a hypothisis- the PCM isn't telling the injectors to fire except during initial cranking. That would explain why it seems to want to start when I first twist the key, but certainly won't run. How do I test that theory?


Thanks for the assistance.

 

[Matt Fisher]

Update:

I picked up a noid test light. It shows the injector firing once when I first try starting my X, and nothing afterwards.

This means the PCM is bad, correct?

Assuming that's the case, the vehicle will be on it's 3rd PCM by Monday...

 

[MadExplorer93]

Update:

I picked up a noid test light. It shows the injector firing once when I first try starting my X, and nothing afterwards.

This means the PCM is bad, correct?

Assuming that's the case, the vehicle will be on it's 3rd PCM by Monday...

Hmm that theory of yours maybe a good one, but is the PCM's you getting NEW or used as forgive me i never read the whole thread again.

I want one of those NOID test kits now as that is a good test for EFI systems for the injectors to see if they are firing when suppose to be, now on the other hand you could have another issue instead the ICM ignition control module, did you try another one of these?

But try a known good PCM again to see if that fixes the issue.

 

[Matt Fisher]

The current PCM did in fact, come from a wrecking yard. Most likely the next one will be a remanufactured one. Although I haven't called Ford to find out the cost on a new one (I bet they only have reman too) due to the expected cost from them ($400?).

I've now tried 3 ICM's. No difference.

The noid that I got is not much more than a light with wires. $26.00

 

[MrShorty]

Update:

I picked up a noid test light. It shows the injector firing once when I first try starting my X, and nothing afterwards.

This means the PCM is bad, correct?

Assuming that's the case, the vehicle will be on it's 3rd PCM by Monday...

No, it doesn't. You reported a CM 211 earlier. The computer won't fire the injectors if it isn't seeing the PIP signal. The PIP signal is how the computer knows the engine is rotating. (If the engine isn't rotating, there's no need to fire the injectors.) The computer not firing the injectors is consistent with a missing PIP signal. If I were in charge of the diagnosis, I'd be back to the DTC's, get a hold of the circuit pinpoint test for a CM 211, and work on that.

 

[Matt Fisher]

No, it doesn't. You reported a CM 211 earlier. The computer won't fire the injectors if it isn't seeing the PIP signal. The PIP signal is how the computer knows the engine is rotating. (If the engine isn't rotating, there's no need to fire the injectors.) The computer not firing the injectors is consistent with a missing PIP signal. If I were in charge of the diagnosis, I'd be back to the DTC's, get a hold of the circuit pinpoint test for a CM 211, and work on that.

On my 94, the computer gets it's signal solely from the crank position sensor, not from a cam sensor, correct? I replaced the CPS yesterday- still not firing.

That would leave either a bad harness, or a bad PCM as the culprit, right?

What's a circuit pinpoint test for CM211?

 

[MrShorty]

Every DTC has a corresponding series of diagnostic steps that the engineers put together to find the root cause of the DTC. These are often referred to as pinpoint tests. You usually need either a factory manual or a professional computer diagnostic manual to read them (I find them at the library).

While it is possible to get a bad CPS right out of the box, for now we can assume the new CPS is good. Which means the problem lies in the wiring between the CPS and the ICM, the ICM itself, the wiring between the ICM and the PCM, or in the PCM itself. If you don't have access to a manual with the pinpoint test in it, then you'll at least need a good wiring diagram.

Your '94 should have a camshaft position sensor (CMP) as well. CMP is used to synchronize the timing of the fuel injectors, and it doesn't usually contribute to a no start. The CMP generates the cylinder id CID signal, and a fault in the CMP is usually accompanied by a CM 214. According to the information I have, a CM 211 gets traced to the CPS and not the CMP.

 

[Matt Fisher]

Slid another PCM in there, fired right up. Thanks for all the help and suggestions.

30K more miles, then it's a gonner.

 

[MadExplorer93]

Just a side note:

If that PCM dies in 30K or sooner or even 50K then i suspect there is a shorting issue some where in the wiring harness or a sensor or else where electronic related on the vehicle. If is is a used PCM well consider it maybe a bad PCM .. lol

PCM's should not just die and die and die, if so then either your totally unlucky or there is a bigger issue else where killing them.

 

[Matt Fisher]

Agreed. At this time I'm going to keep my fingers crossed and hope that I was just "PCM challenged"

If I start having issues again, the PCM will likely be the first place I look.

 

[mull8723]

any updates

Just checking to see if the pcm is still working. Im having the same issue and wondering if there has been any changes

 

[Matt Fisher]

The Explorer is long gone (the thread is 7 years old). I vaguely remember that it was headed to Mexico, but am not sure.

Actually going to be considering a new vehicle soon, my Dodge 4x4 is getting a little longer in the tooth than I want. Getting older seems to mean I'm less willing to put up with even the potential for reliability issues.