An error in the KOEO codes means there is a problem with talking to that device at that particular moment in time. IOW if a code shows up in KOEO, that means the device is presently failing at that precise moment in time.

WHY it might be failing is what you as a mechanic have to figure out. It could be the device is just worn out and failing, but it could also be caused by miswiring/damaged wires/bad connections/etc.

Stuff in CM is what the computer remembers from the previous n driving cycles (I forget what n stands for).

Start with the first error in the list (the one displayed first by the computer) as the top-level errors (those with the lowest numeric value) are most important and failures there can often what can appear as errors made by other devices.

A quick google says 22 looks to be the MAP/BARO sensor.

Have you run KOER yet?

 

Maybe I said that wrong....

In all cases, the engine should be fully warmed up to normal operating temperatures before doing any of these tests.

KOEO - the computer does a basic integrity check... can it talk to all its sensors, and are they all reporting values within their expected ranges. If not, errors are reported.

CM - What is remembered about the previous n normal-operation driving cycles

KOER - The computer checks for normally-expected values reported by its sensors, it also tries to do some basic controlling of the engine (raise & lower the idle speed, for example) and looks to see if

1) it can in fact perform those actions, and
2) the sensors accurately report the resulting changes

 

Thanks CTUBUTIS. I have not yet performed the KOER. I figured I should sort out the KOEO first. Ill start with the MAP. Ill check online to see expected values for this sensor at rest and with vacuum.

The engine was warmed up yesterday for the test but not this morning. Either way the MAP looks to be first in line.

I wont have time until Thursday to work on this again, Ill let you know what I find.

Craig

 

Hey, Craig,

This might help you (the photobucket link below)...

This is my copy of the1986 FoMoCo Engine/Emissions Diagnosis shop manual:




All the Quicktest Howto (IOW how to pull codes) pages are in one of my photobucket albums:

<iframe src="http://s1266.photobucket.com/user/ctubutis/embed/slideshow/Ford%20EEC-IV%20Quick%20Test" height="360" width="480"></iframe>

 

Great help, ctubutis!!!

 

Good information. So going by those instructions my first action is to take care of code 22 from the KOEO which is a MAP error. The book says DF1. Would you be willing to take a photo of that page CTUBUTIS?
Checking the MAP sensor with the KOEO-- I have 5volts to the sensor through the light color wire (may be yellow with a stripe) I have 5volts to the middle wire (blue) and I have a good ground through the black wire.

I need to get a vacuum pump to check and see if the MAP signal is changing with a change in vacuum. Vacuum with guage is $55, new MAP is $45.

Is the MAP signal change a change in volts or frequency?

Craig

 

Quick test with a syringe hooked to the map. Pulled the syringe plunger and no change in voltage from the map middle wire. Also the map doesn't hold a vacuum which I think it should.

Is my logic correct if I say there is a good possibility the map sensor is broken?

 

Your logic sounds pretty good to me.

I have DF0 - DF22 in a photobucket album; they're ordered backwards and some might be hard to read but give it a shot and let me know:

DF Photos by ctubutis | Photobucket

 

Wow. Well, I put a new MAP sensor in and the truck runs so much better. It feels good to have solved the major part of the problem and I could not have done it without your help CTUBUTIS and 1986F150six. Ill keep working on the truck getting it back up to better standard because I know there are other things wrong mechanically.

I learned alot and am pretty pleased.

Thanks
Craig

PS ill run another quick test with the code reader when it stops raining and let you know what that says.

 

Snow tonight in the higher elevations, supposed to be 80° next week.

Yeah, the MAP is pretty crucial to the thing running well...

 

Oh bother, I'm late to this party.
Looks like you've got it handled. Thanks to all who helped him out.
One more thing to look into-check the engine vacuum. if the intake manifold gasket is toast, it'll leak air into the engine, driving the air/fuel mixture lean and cause all sorts of driveability issues. BTDT.
You write that you rebuilt the carb- or did you replace it?
Thanks David for the PM, sorry I got here late.
Thanks to Chris as well.

 

When you do, remember to throttle it shortly after you begin the test so you don't get a throttle position sensor code. Good luck.

 

Hello wyowanderer. Its a rebuilt carb from guaranteed carbs. It looked identical to the old one. Thanks for the throttle heads up, I'll do that for sure. Monday I have some time to check it out and I'll post the results. What's the best way to check for manifold leaks?

Craig

 

Posting results, but late.

So today I checked the codes again. Still have in KOEO- 22,51,53,68 which are (if I am correct) MAP,Engine coolant temp too high,Throttle position sensor too high,Idle tracking switch. I have a new MAP, Temp sensor and throttle position sensor.

The truck runs better than it ever has so.... The temp gauge does not work (barely deflects when warmed up, not even up to cold).

All of these sensors have a common wire, black with a white stripe. I confirmed this on an autozone wiring diagram. So I figured that that wire was faulty somewhere. I checked the resistance at the temp sensor (warm) 3.5ohms, and at the computer 3.5ohms.

I pulled the instrument cluster and cleaned the connections. No change.

Questions 1) Could the black/white stripe wire still be bad with the same reading at the sensor and the computer?
2) Could the gauge be bad and cause all of the problems?
3) Is the computer starting to fail?
4) How does the temp signal get from the computer to the gauge? I dont see how these are connected? (seems like a dumb question but I dont see the wiring harness from the computer to the instrument cluster).

Thanks again guys.
Craig

 

A whole lot cheaper and easier to convert to non-feedback carburetor and different ignition. You can convert the emissions systems to vacuum control and get rid of the computer. Not too difficult and easier to deal with in the long run.

Just my 2 cents..