Hello everyone,

I have a 95 ford f150 eddie baur 5.8 351w. Just under 200k milage.

Check engine light came on. Got the classic P0500 code using data link inside the cab with my cheap code reader. All it states is I have Speed Sensor A issue.

Before this happened I was driving on highway and the cruise control was acting up. I'd set the cruise at 70mph and then a few minutes would go by and the cruise control would quit and then I would feel a loss of power. I would pull over. Put truck in Park and leave running. Continued driving all was fine for a hour until the same thing would happen. This time the OD light started flashing also.

Also Recently the ASB light would come on randomly and transmission would slam into gear. This was random and would usually go away.

After reading several other posts I tried replacing the sensor in the rear diff. Only got worse when I tried two different sensors. Wouldn't even shift into second gear and lost reading of all speed. So I put the original sensor back in.

Truck would run amazing on some days and then on others the ABS light comes on. Shifts hard. OD light might start blinking. And now as of yesterday the weird cruise control issue and check engine light on putting out P0500 Speed Sensor A code.

Like I said some days the truck runs great like nothing is wrong. Other days I feel like not even driving it.

Now here is the kicker. I have read and researched enough to try and use the OBD 1 reader to further diagnosis the problem. Problem is my truck is missing it's EEC-IV system. Its missing. I have looked everywhere. The ECC self test plug is simply not inside my engine bay on drivers side door fender.

So I feel stuck. I took the truck to my local mechanic I trust and he said he can fix the code because the truck is a OBD1 system.

Not sure what to do. How do I continue to run diagnostics? Does anyone know how I could reinstall a EEC self test plug?

 

What the hell....

FIRST. Go underhood to your VECI. its on your hood by the windshield at least on mine, picture that and send it please. you sent absolutely NO PICTURES of anything, so Im not sure what youre expecting, especially with a rambling that seems contradictory lol.

VECI should state in plain words what the truck meets for emissions and what systems it has.

here is a 96 5.0 to compare

 

here is a 95 5.8

 

 

You sure most definitely do not have a 1995 as you have a 1996

you have a truck that is NOT compliant to obd2 fully, but it is partially it seems. You have a DLC under the dash your scan tool connected to with obd2 port? Then you do not have a EEC-IV plug and truck, because unless there is some unicorn EEC-iV with OBD2 integrations you have EEC-V and you have a partial OBD2 vehicle.

 

Read your live Data for OBD2 on a reader, if you have a vehicle speed data parameter, monitor it and your speedometer and see what you see. if you can log, even better

 

Thanks for the reply.

So when diagnosing I should be using a OBD2 reader? It does say it’s a 95 but made in 10/95. Very strange I guess.

so I went back out to check the live info on the reader I have and of course the check engine light is off and only the ABS light is on. I’m sure it will reappear and I’ll check the live info then.

is there anything I should be looking for in the live feed info?

thanks again for your help.

 

i

the light being off means nothing for this situation, connect your tool and read the codes and check the data

you may even have freeze frames but I doubt it for that code

specificaly looking for wheel speed and that’s all I can think of, but your speed sensor not working is consistent with your symptoms tbh so I would say we are looking at a wire break or loose connection or corrosion. But while moving it helps to be sure your Speedo and the live data for Speedo say the same

 

if your truc says 1995 on the title you better check the vin to match the veci because you’re driving a 96 according to the hood label

 

As stated in an earlier response the manufacturing date of 10/95 does not make it a 1995 model year vehicle. VIN position 10 denotes what model year the vehicle is. In your case I would bet it is the letter "T" which is a 1996. 1996 model year F150 and Broncos were OBD-II.

Since you are getting OBD-II Code P0500 that does indicate the VSS signal is erratic or missing completely. The Yellow ABS light is another indication the VSS signal is degraded.

Pull the RABS codes to see what is triggering the Yellow ABS lamp: RABS Flashout Codes

 

So I just tested the VSS with the data link while moving. Got up to 50mph and was accurate the whole time. ABS light still on. No OD flashing this time. And truck is shifting smooth again…

 

You probably have a damaged wire between the VSS and the PCM. Sometimes it makes the connection, sometimes it does not.

 

Partially OBDII in this case, hes only partially OBD2 compliant(99 was the deadline to become compliant) as you see on his label, he just meets 1996 certifications, but my 4.9 "meets OBD2"

heavy duty light duty vehicles got till 2004, so my dads f350 (2001 or 3 or somehting) it meets the requirements that model year but not OBD2

 

Alright. Would it be smart to get new connectors and or wiring hardness?

 

for the VSS? Not at this moment, find the issue. If you go to your rear axle and carefully pull the connector, verify the wire has no breaks in the insulation, the wire is not pulled tightly when on the axle(The harness may be tugging with axle movement?)
then verify the terminals are clean and not spread open(Loose fit)

this is my Car, but look at that sensor (TPS on my engine) the wiring is kinked looking, and when the harness had conduit and was together, it was pulled tightly, this can cause your issue and is not as obvious a spot unless its somehow done very obvious (not common)

this is close to the shape/design I think... if not you can look and you will see, but once you verify the end thats on the sesnro, simply follow the harness and see if you notice any weird things like obvious detours, pinching, rubbed sheathing etc. I think its in a conduit and joins another harness,but it may go directly along frame rail and by the RABS thing too, you would have to see.

If you have a harness to unwrap, its tedious but its good practice, a seam cutter(sewing) helps for vinyl tape. before getting too wild opening tho, if you didnt notice huge issues odwn there, go to your PCM and nearby and look at the wiring to it, notice issues?