OBD1 for Dummies . . . . .
#1
#3
Seeing as the response has been tepid, here are the symptoms:
Cold start, 90% of the time the truck runs like new as long and as far as you want to drive it. . . until shut off and it sits a bit:
Then, when just moderately warm after restarting: It will start and want to run at a high idle (1500) and you can't kick it to the typical idle (700).
When first driving it after a restart like this, it will idle low and rough at a stop light and stumble when accelerating away. It will continue to stumble and not accelerate until I give at about 1/2 throttle and it will take off running fine.
On a couple of occasions, when running bad, I have been able to put it in neutral and rev the engine to 4500 rpm +, two or three times in quick succession and it will also run like a new truck.
No vac leaks have been found.
When it is at operating temp, it will run like a new truck.
Occasional flash of CEL, nothing constant and also a very rare 3 or 4 flash of CEL when first starting but never consistent either hot or cold.
There are no codes when I scan the ECM.
All computer sensors, vacuum motors, vac switches, etc, IAC, EGR, distributor are new.
The only things not changed out yet are the ECM itself, tranny speed sensor and knock sensor.
BTW, 6 liter tune up, K&N, shorty headers and stainless cat back duals.
Cold start, 90% of the time the truck runs like new as long and as far as you want to drive it. . . until shut off and it sits a bit:
Then, when just moderately warm after restarting: It will start and want to run at a high idle (1500) and you can't kick it to the typical idle (700).
When first driving it after a restart like this, it will idle low and rough at a stop light and stumble when accelerating away. It will continue to stumble and not accelerate until I give at about 1/2 throttle and it will take off running fine.
On a couple of occasions, when running bad, I have been able to put it in neutral and rev the engine to 4500 rpm +, two or three times in quick succession and it will also run like a new truck.
No vac leaks have been found.
When it is at operating temp, it will run like a new truck.
Occasional flash of CEL, nothing constant and also a very rare 3 or 4 flash of CEL when first starting but never consistent either hot or cold.
There are no codes when I scan the ECM.
All computer sensors, vacuum motors, vac switches, etc, IAC, EGR, distributor are new.
The only things not changed out yet are the ECM itself, tranny speed sensor and knock sensor.
BTW, 6 liter tune up, K&N, shorty headers and stainless cat back duals.
Last edited by 24 Carat; 03-24-2016 at 02:12 PM. Reason: add info
#4
You stated no codes from the PCM.
Clarify "No Codes"
If you can't retrieve codes or you don't receive a System Pass code of either 11 or 111, you have a problem with the PCM or DLC connector pins.
Try cleaning them up with a nail file or something and try again. If nothing, then your symptoms are pointing to a failing PCM, most likely cause from leaking, bulging capacitors.
Clarify "No Codes"
If you can't retrieve codes or you don't receive a System Pass code of either 11 or 111, you have a problem with the PCM or DLC connector pins.
Try cleaning them up with a nail file or something and try again. If nothing, then your symptoms are pointing to a failing PCM, most likely cause from leaking, bulging capacitors.
#5
You stated no codes from the PCM.
Clarify "No Codes"
If you can't retrieve codes or you don't receive a System Pass code of either 11 or 111, you have a problem with the PCM or DLC connector pins.
Try cleaning them up with a nail file or something and try again. If nothing, then your symptoms are pointing to a failing PCM, most likely cause from leaking, bulging capacitors.
Clarify "No Codes"
If you can't retrieve codes or you don't receive a System Pass code of either 11 or 111, you have a problem with the PCM or DLC connector pins.
Try cleaning them up with a nail file or something and try again. If nothing, then your symptoms are pointing to a failing PCM, most likely cause from leaking, bulging capacitors.
Is there any common understanding of the possibility of the EEC being bad? Do they function correctly and then just quit or is it possible to get bizarre performance as it degrades? Again back to it degrading, does it or just die?
#6
Just Google "Failing, failed Capacitors Ford OBD" or "A9P PCM failed Capacitors"
The last 2 weeks I have read several posts regarding failed PCM's and most were the Capacitors were leaking or had corroded off the board due to the acidic electrolyte fluid.
I would pull the PCM since you said that you retrieved a System Pass 11 and you know that the CEL has flashed and been illuminated a number of times.
The last 2 weeks I have read several posts regarding failed PCM's and most were the Capacitors were leaking or had corroded off the board due to the acidic electrolyte fluid.
I would pull the PCM since you said that you retrieved a System Pass 11 and you know that the CEL has flashed and been illuminated a number of times.
#7
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#8
Sorry my response was less than lukewarm...
We tend to thrive on information, definitive questions & pictures for some reason.
You wanted OBD I tutorial for OBS & FFI is the start for the technical literate. Glad you made it back & hope you have success with your troubleshooting goal.
Here is my tale of capacitor leak & lack of code woe:
https://www.ford-trucks.com/forums/1...nd-thread.html
We tend to thrive on information, definitive questions & pictures for some reason.
You wanted OBD I tutorial for OBS & FFI is the start for the technical literate. Glad you made it back & hope you have success with your troubleshooting goal.
Here is my tale of capacitor leak & lack of code woe:
https://www.ford-trucks.com/forums/1...nd-thread.html
#9
I am so tickled to have an avenue to resolve this I am about to **** myself.
I'm not shy about replacing the capacitors but is there a member seeing this that would have a repaired unit, or more likely, a source for reconditioned that replaces the caps as a matter of this weakness?
How many flavors are there for this truck? I've read that PN or color coding on the unit makes a particular truck dependent on an exact replacement ????
I'm not shy about replacing the capacitors but is there a member seeing this that would have a repaired unit, or more likely, a source for reconditioned that replaces the caps as a matter of this weakness?
How many flavors are there for this truck? I've read that PN or color coding on the unit makes a particular truck dependent on an exact replacement ????
#10
On your door frame is a tag & next to it is a calibration code that corresponds to the computer it came from the factory with. This will give the exact "batch code" that you can shop for. Many will work in a pinch if you meet the major parameters. Year, engine size generally & auto trans code.
Not mine:
Well that should warm you up just fine...
Not mine:
Well that should warm you up just fine...
#12
I do not know how you are trying to read the codes but you will not get a 11 code with a 1995 5.0L truck.
To get the all clear of codes with this truck the code readout would be:
111, 111, 1, 111, 111
The last two sets off 111 are the CM codes and the first two sets of 111 are the KOEO codes. The center 1 is a separator space code between the two code readouts.
Any time the CEL (MIL) flashes it will set a code in CM. No ifs ands or buts about it.
I think you have many codes in CM that you have not read.
Note if you did get a 11 with KOEO readout then you have the wrong era computer in the truck and you need to post the calibration code as in the photo above (example in photo of "4-54L-R00").
Then we will try to post the right PCM computer engineering number (the number on the part) and the Ford part number that only Ford uses.
To get the all clear of codes with this truck the code readout would be:
111, 111, 1, 111, 111
The last two sets off 111 are the CM codes and the first two sets of 111 are the KOEO codes. The center 1 is a separator space code between the two code readouts.
Any time the CEL (MIL) flashes it will set a code in CM. No ifs ands or buts about it.
I think you have many codes in CM that you have not read.
Note if you did get a 11 with KOEO readout then you have the wrong era computer in the truck and you need to post the calibration code as in the photo above (example in photo of "4-54L-R00").
Then we will try to post the right PCM computer engineering number (the number on the part) and the Ford part number that only Ford uses.
#15
I'm open for suggestions on sources for the EEC.
Most I have emailed or spoken to are nothing more than used parts brokers and wouldn't know a capacitor from a banana.
Test the unit, stick a part number on it and move'm out seems to be the mantra.
One place will attach a lifetime warranty that is non transferable with no core charge so going that route and then changing out the caps in mine seems to be the common sense approach.
Most I have emailed or spoken to are nothing more than used parts brokers and wouldn't know a capacitor from a banana.
Test the unit, stick a part number on it and move'm out seems to be the mantra.
One place will attach a lifetime warranty that is non transferable with no core charge so going that route and then changing out the caps in mine seems to be the common sense approach.