I hoping someone can point me in a fast easy direction .

I bought a 88 f250 5.8 5speed and it ran great , I drove it all over for a month went up to the mountains in the mud and snow and all over town for a month .
I did the oil change, spark plugs and air filter , I drove it everyday and then one morning the check engine light came on for a few seconds and I felt the truck run bad and then the light went off and ran good .
then a couple days later it came on and stayed on with the trunk running kind of poor buy mostly when I would lug it in 3rd or 4th Gear until it got up in rpm then it feels fine . Checked the codes and got code 22 . Of course checked vacuum lines , grounds and wiring with no luck .
then the battery went dead so I bought a new battery and over night it went dead , the alternator and or voltage regulator went bad so I replaced both and now it starts and charged but still have code 22 .
symptoms are it stumbles and pops inside the Intake but only under load , going almost too slow for 3rd gear .

Did the map sensor really go bad just like that?
or did the new motocraft spark plugs cause this ?
I changed the spark plugs a week before .
code 22 pops up every time .

does anyone have any input ?
it seems to run great past that low rpm lug stage .
sometimes it will also die if I let it idle .

 

Yes the MAP conforms to the Murphy's Law theory. Not sure on yours but my year can be checked with a meter. Also check the vacuum line it uses and replace it if anything looks rotted or not in good shape. If it looks bad replace it first if you don't put a meter on it. If I looks OK then meter it or replace it. Sandy

 

Ok thanks .
Would spark plugs not gapped right cause problems that would give code 22 ?

It seems like it happened less then a week after I changed the spark plugs and I never checked the gap because they are motocraft from the ford dealer . I figured they were already gapped properly

 

Spark Plugs will not cause Code 22...ever.

I am not aware Ford pre-gaps their plugs. Always best to verify.

How are you pulling the codes and during which test was this code displayed?

 

KOEO . I check many time and I get 22

I honestly don't have much money so I'm trying not to replace anything I don' need to right away .

how about wiring harness being too close to the block getting too hot ?

I feel like the section of harness that gos to the map and o2 sensor wasn't in the correct spot and resting on the back of the block possibly getting too hot , I moved it and inspected the wires and they look fine .

I keeping thinking it has to be the map or pcm it' self . Or wire damage .
am I on the right track ?

 

 

Never trust the factory gap on plugs. As I recall all my Motorcraft plugs were off. Pull them all and I think you will have the same results as I did. On the code 22, think MAP but keep the pcm in the line up. Sandy

 

I don't currently have access to a multi meeter that does frequency .
Any other ways I can rule out the map ?

thanks

 

Part 1 -Manifold Absolute Pressure MAP Sensor Test (Ford 4.9L, 5.0L, 5.8L) Look at test 2

 

Ok thanks I will test soon .

but , in the testing procedure it mentions that low compression , rough idle could cause a map code . Or fuel issue ?
how likely is this ?

 

HOW are you pulling the codes? Counting flashes or using a code reader?


No you are not. You are jumping to conclusions.

 

Completely false.


Zero probability and no chance

 

Yes counting flashes .
Ok sorry I just read the testing procedures carefully and questioned that part .

so I tested the power and the ground and its getting full power but o my 4.9 on the ground side

 

Common problem: When counting flashes it's very easy to mis-interpret the System Pass Code 11 as Code "22". When starting the KOEO tests the computer will run a series of tests. If nothing is flagged as wrong it will display System Pass Code 11. That means you will see a short flash, pause, then another flash...then a longer pause...then a short flash, pause, then another flash. The codes, even System Pass, are displayed twice.

Then there will be a long pause, another flash (aka separator flash between the KOEO tests display and the Stored Code display) then any Stored Codes will be displayed in the same fashion. If there are no stored codes you will get System Pass Code 11 (twice, just like the KOEO test display).

I highly suspect you are getting the System Pass Code 11.

Since you did get a Check Engine Light, you probably have a stored code(s)...but the caveat is if you remove the test jumper before the KOEO codes and CM codes are completed the CM (Stored Codes) are erased.

 

Oops I didn't stab the wire deep enough I tried again and got 12.5

Thanks I very much considered that . I searched and read a lot before posting here .

The light flashes twice with less a second or less between the 2 and then waits probably 3 seconds and flashes twice again with a second or less between .
And it shows code 22 stored along with 11