1983 - 2012 Ranger & B-Series All Ford Ranger and Mazda B-Series models

1998 Ranger ECM failure, again and again Help Please

Thread Tools
 
Search this Thread
 
  #1  
Old 12-04-2011, 09:40 AM
antiqueynot's Avatar
antiqueynot
antiqueynot is offline
Senior User
Thread Starter
Join Date: Oct 2006
Location: Hickory, NC
Posts: 127
Likes: 0
Received 2 Likes on 2 Posts
1998 Ranger ECM failure, again and again Help Please

I got a lot of help about two months ago when my ECM, and alternator and battery, failed. After about two months from the initial replacement, Cardone rebult ECM was installed, while driving down the road, the truck died. Determined no injector action, no fuel pump action and no communication with ECM through OBD. Got another Cardone rebuilt ECM, lasted about 20 minutes, just idling in front of house and died. Got another , now has done the same thing. Parts store, after the third ECM, says "must be a problem with the truck". I have spoken with a friend who is Ford knowledgeable and he has never had this problem, never had something else on Rangers bring down ECM, but has experiance with bad rebuilt ECMs from Cardone. I don't want to blame Cardone, I just want to get my truck reliable again. Any thoughts? I have thoroughly checked grounds at battery and at ECM, and looked all over for signs of trouble. I would very much appreciate any ideas,
Thank You,
Tony
 
  #2  
Old 12-04-2011, 09:49 AM
antiqueynot's Avatar
antiqueynot
antiqueynot is offline
Senior User
Thread Starter
Join Date: Oct 2006
Location: Hickory, NC
Posts: 127
Likes: 0
Received 2 Likes on 2 Posts
Just need to add, that I ordered and should get a good used ECM on Monday, btu I don't want to blow that one up if I am doing something especially stupid,
Thanks,
Tony

Just in case Cardone # 788266 , Ford # F87F-12A650-APC, these have been REALLY hard to find.
 
  #3  
Old 12-04-2011, 11:52 AM
pawpaw's Avatar
pawpaw
pawpaw is offline
Moderator
Join Date: Jan 2004
Location: SW Va
Posts: 13,774
Received 73 Likes on 71 Posts
I agree, something sounds suspicious.

Have you been having any other problems, like lights burning out, or flickering???? If so, have the alternator bench tested for under load voltage regulation.

Is the battery ok???? It acts as a noise filter, to level out electrical system voltage spikes, so don't disconnect it with the vehicle running, as the computer won't like that. This would also pertain to loose faulty battery cables, or their end of cable lug connectors & wire strand connections inside their lugs, not just where the wires lug makes it's vehicle connection.

Once had a bad B+ cable at the starter motor end, where it's wire strands connected inside to the cables end lug. There was corrosion out of sight, underneath the insulation, causing an intermittent high resistance connection to the lug. That kind of problem is like having the cable come disconnected, so if it's making & breaking contact, it'll cause voltage spikes on the line & if it's a cable coming from, or going to the alternator, or underhood power distribution box, those online voltage spikes can take the computer out.

So checking your electrical connections was a good idea, maybe go a step further & give your B+ & B- cables to the alternator, power distribution box, engine & body a wiggle test while monitoring end to end resistance, to see if any go high resistance, or open circuit. Replace any that have broken wire strands at their lug ends, or show corrosion.

The connections between the battery, alternator, engine & body must be clean, bright & tight. Check the computers firewall electrical connector pins/sockets & wires for bent/broken pins, spread sockets, corrosion, cut insulation, broken wires, ect.

Do you have any aftermarket equiptment installed, if so turn it off, or disconnect it until it's checked out.

Let us know what you find.
 
  #4  
Old 12-04-2011, 12:08 PM
antiqueynot's Avatar
antiqueynot
antiqueynot is offline
Senior User
Thread Starter
Join Date: Oct 2006
Location: Hickory, NC
Posts: 127
Likes: 0
Received 2 Likes on 2 Posts
Hey PawPaw,
Coming to my rescue again aren't you? Thanks. I will be rechecking the cables and remember that the supplemental lead at the negative cable end is a trouble point. When the truck first quit two months ago, it surged twice, engine and lights, and then died. No such pattern of failure now. It just dies. First, three weeks ago, just driving down the road. Lately, twice, it has died just idling in front of my house after starting and being turned off a few times. I've been advised that the DPFE sensors can bring things to a halt. I am not familiar with these. Are they an engine temperature resposive sensor? I ask this because now it seems that the truck could be dying when approaching normal temps. Just a thought. As always, I appreciate your thoughts and experiance and you will again hear the Yahoo when I get this figured out,
Tony
 
  #5  
Old 12-04-2011, 03:52 PM
pawpaw's Avatar
pawpaw
pawpaw is offline
Moderator
Join Date: Jan 2004
Location: SW Va
Posts: 13,774
Received 73 Likes on 71 Posts
Yup the DPFE sensor can cause mischief, but you didn't post any trouble codes, saying the computer was unhappy with it & the DPFE sensor wouldn't likely cause the computer to go belly up imo!!!!! It senses the pressure difference between intake & exhaust manifolds & sends the computer a feedback signal to have it calculate how often & long the EGR valve needs to open to feed exhaust into the intake manifold, to lower combustion chamber temps to control N2O & prevent spark knock. BUT the EGR valve isn't online when the engine is cold, or at idle, so imo the DPFE sensor isn't likely causing the engine to stall & isn't likely to be causing the computer to fail.

BUT something electrical acting out, causing online voltage spikes, sure can. Something like an RF transmitter with higher than normal output, not properly installed, some piece of faulty aftermarket equipment, forgetting to disconnect the battery when recharging it & having the battery charger with excessive ripple fry things, acting out alternator voltage regulator, faulty battery cables, shorting battery cells. Lots of unusual possibilities, so keep an open mind when trying to think through your trouble shoot, no matter what you've recently done, leave everything on the suspect list until you can do some trouble shooting to narrow the suspect list down some.

I agree with doing some tests before installing the new computer, as having this many computers fail so soon, sure smacks of something electrical frying them.

If you decide to have the alternator tested, consider pulling the battery & have it load tested too.

More thoughts for pondering, let us know how it goes.
 

Last edited by pawpaw; 10-14-2023 at 06:23 PM. Reason: Spelling
  #6  
Old 12-04-2011, 04:36 PM
michigan66's Avatar
michigan66
michigan66 is offline
Posting Guru
Join Date: Mar 2005
Location: Dexter, MI
Posts: 1,533
Likes: 0
Received 1 Like on 1 Post
In addition to all the good suggestions from Pawpaw, have you checked the voltage output of the alternator? Also, check all wiring to and from the alternator. I agree that something is creating voltage spikes and is taking other things out as a result.

Let us know how you make out.
 
  #7  
Old 12-04-2011, 05:39 PM
antiqueynot's Avatar
antiqueynot
antiqueynot is offline
Senior User
Thread Starter
Join Date: Oct 2006
Location: Hickory, NC
Posts: 127
Likes: 0
Received 2 Likes on 2 Posts
PawPaw and Michigan66,
Thanks for the responses. I replaced the alternator with a rebuilt 2 months ago at original failure. There are no indications of low voltage from the alternator, but I can take it to be tested no charge. Battery voltage read low 12's before starting the last time. The only thing I can see from what PawPaw said is that it may be when the DPFE is starting to come into play, with the engine warming, that this latest fault appears. Is there a possible coorelation between the engine warming and a sensor or relay coming into play and causing an electrical fault. I must admit I'm pretty stumped so far,
Thanks again,
Tony
 
  #8  
Old 12-04-2011, 05:57 PM
pawpaw's Avatar
pawpaw
pawpaw is offline
Moderator
Join Date: Jan 2004
Location: SW Va
Posts: 13,774
Received 73 Likes on 71 Posts
To be fully charged, the battery should be at least 12.6 volts or higher with the engine & all electrical loads off. Engine running at say 2000 rpm, the voltage across the battery posts should be between 14-15 volts DC.

So, with the battery in the low twelves voltage wise, suggests that something is wrong with either the battery, or alternator, or both, the battery cables, or their connections.
 
  #9  
Old 12-04-2011, 08:45 PM
antiqueynot's Avatar
antiqueynot
antiqueynot is offline
Senior User
Thread Starter
Join Date: Oct 2006
Location: Hickory, NC
Posts: 127
Likes: 0
Received 2 Likes on 2 Posts
PawPaw,
I will have the alternator checked, but I just remembered something. On the last two Cardone rebuilt ECM's, the tag said APA. My ECM has the last three characters of APC. When I asked at the parts store, they told me no problem. Is this a concern? Sorry I just remembered this,
Thanks,
Tony
 
  #10  
Old 12-04-2011, 09:34 PM
pawpaw's Avatar
pawpaw
pawpaw is offline
Moderator
Join Date: Jan 2004
Location: SW Va
Posts: 13,774
Received 73 Likes on 71 Posts
I don't know the significance of the computers last three letters. Does the replacement computer have the same model number as the origional computer????

EDIT: Another thought, if you don't know the vehicles OEM computers model number, go to the rebuilders web site, enter your vehicles particulars & see what they have to say is the correct number.

This is what I did on the computer I recently replaced on my 94 Taurus 3.8L, to check Advance Autos online P/N. Turns out they were both in agreement with my OEM computers model number & the replacement computer is working fine, no more intermittent/random stalls!!!!
 
  #11  
Old 12-05-2011, 05:13 AM
antiqueynot's Avatar
antiqueynot
antiqueynot is offline
Senior User
Thread Starter
Join Date: Oct 2006
Location: Hickory, NC
Posts: 127
Likes: 0
Received 2 Likes on 2 Posts
PawPaw,
The part numbers on the Cardone boxes and units are what is listed for my vehicle exactly. I was just asking if this was a possibility. I will be replacing the DPFE sensor and PCM and fuel pump relays today. My intent is to then plug in the new, good used ECM and just turn the key to the ON position and verify that I have OBD communication again, I have done this with each of the previous ECMs. At that point, I guess I will see if the thing will run and just take a chance. This has become so frustrating. I surely appreciate all your help now and in the past,
Tony
 
  #12  
Old 12-05-2011, 08:25 AM
pawpaw's Avatar
pawpaw
pawpaw is offline
Moderator
Join Date: Jan 2004
Location: SW Va
Posts: 13,774
Received 73 Likes on 71 Posts
I forgot to ask, when the ECM's failed, did the dash warning lights go dead too????
 
  #13  
Old 12-05-2011, 10:36 AM
antiqueynot's Avatar
antiqueynot
antiqueynot is offline
Senior User
Thread Starter
Join Date: Oct 2006
Location: Hickory, NC
Posts: 127
Likes: 0
Received 2 Likes on 2 Posts
PawPaw,
No, dash lights are all there, gauges appear to respond normally too. I am intending to get a DPFE sensor, and PCM and fuel pump relays today. With the previous failures at least, I still had spark (sprayed ether into the throttle body and it fired while cranking), but no injector or fuel pump action. The biggy has been no OBD communication, that appears to be a real puzzling situation,
Thanks as always,
Tony
 
  #14  
Old 12-05-2011, 11:09 AM
pawpaw's Avatar
pawpaw
pawpaw is offline
Moderator
Join Date: Jan 2004
Location: SW Va
Posts: 13,774
Received 73 Likes on 71 Posts
OK, thats good input, so the latest round of problems seem to be fuel delivery related & no ECM communication. SO, for the ECM communication problem, check your in cabin cigar lighter fuse, Then check the DLC for B+ at KOEO. If no B+ at the DLC, inspect it's pins/sockets & wiring back to the computer firewall electrical connector. Maybe do a wiggle test on the wiring.

I was about to suggest a round of under hood power relay swaps to see if any positive changes happened but I see your going to replace some of the suspect power relays, so it'll be interesting to hear how it goes.
 
  #15  
Old 12-05-2011, 11:36 AM
antiqueynot's Avatar
antiqueynot
antiqueynot is offline
Senior User
Thread Starter
Join Date: Oct 2006
Location: Hickory, NC
Posts: 127
Likes: 0
Received 2 Likes on 2 Posts
PawPaw,
All along there has been battery voltage at pin 16 of the DLC. I was amuased and delighted to hear about the cigarette lighter fuse check for no OBD, however this has been good all along. I beling to an online group of about 75,000 mechanics from around the world and posted a help request there too. I have recieved replies mostly from two schools. One is rebuilt ECM's are problematic and just plug in an OEM, or, you need to check all sensors and relays, back probe, get a break out box, check for bad wiring etc. The trouble I am having with that is that the failure happens just sitting there, the last two times. I install the replacement Cardone ECM, start and turn off the truck a couple of times, move it about 15 feet from my shop to in front of my house, turn it off, start it the next day, it runs for 5 to 10 minutes, and then shuts off, won't restart, and no OBD, fuel injector, or fuel pump. I am now of the feeling that I will install a new DPFE sensor, new fuel pump and PCM relays, plug in the good, used ECM and cross my fingers. If it does start and run, and stay running, I will be nice to Advance Auto Parts, but it says "warrentied for 1 year" right on the receipt. I must say that the folks at my local Advance have been very nice but now feel that there is a problem with my truck and seem reluctant to warranty this ECM again. I haven't been told this directly but I get this impression. Thank you so very much for your repeated help in this PawPaw,
Sincerely,
Tony
 

Last edited by antiqueynot; 12-05-2011 at 11:38 AM. Reason: missplellings


Quick Reply: 1998 Ranger ECM failure, again and again Help Please



All times are GMT -5. The time now is 06:52 PM.