Pulling Codes from a 1994 Ford Ranger-----

[dpfurby]

I have a 1994 Ranger with the check engine light, the light comes on every morning and afternoon-- at the same place to and from work. Light stays on till I shut off the engine. Seems to come on when the engine gets to operating temp.

I believe after looking thru the net that this model has the Ford EEC-IV setup.

Uses the "blinks" on the check engine light to get the codes.

After looking at the hookup diagram I see that an analog voltmeter is hooked up also. What in the test are we using the voltmeter for?

Could someone refer me to a good write up on the code pulling ??

Thanks!!!

 

[fastpakr]

You can use either the voltmeter or the check engine light to read the codes. There's no need for both. The voltmeter is more useful on the models that had EEC-IV before check engine lights were installed in the instrument cluster. Since yours actually has the light, that's an easier method to follow.

 

[bmerr98]

I had a CEL acting like that a while back. Ended up being a bad egr valve. The diaphragm was leaking and causing a lean code. Smoke test it if you get a chance. If yours has an egr valve it's a prime suspect.

 

[tmcalavy]

Actually, after going through the ordeal of pulling codes from an EEC-IV system on a 90 F150 and my current 93 Ranger, using the analog meter is easier cause its easier to see the needle sweep/move than the CEL flash. Google pulling codes from EEC-IV and you'll get some hits on how to hook up the meter to the EEC box under your hood on the driver's side...pretty simple, just requires a jumper wire to do it. After you hook up the meter, you turn the key on and the EEC goes through its diagnostic test and readout. It logs/shows you codes by the needle sweeping...for example a code 51 is five sweeps-pause-one sweep. Just can't remember if the EEC codes are two digit or three...I think they are two, but may be wrong. I used to have a page bookmarked on how to do it, but new laptop doesn't have all my old bookmarks available just yet. The EGR advice is good, too. Mine shows the CEL occasionally. When it does I run a can of sea foam through a tank of high-test shit-anol gas, or go to the real station and get 100% ethyl gas, then run the hound out of it down the highway. That's generally enough to make mine go away and stay away for a few months...then repeat ad nauseum. Wish there was a decent manual for 2nd generation Rangers that shows test procedures and electrical values for checking the various sensors...your codes may indicate a sensor out of range or not reading at all...that's the best way to keep from throwing $$$ at an unknown problem, and my Haynes manual for the 93 Ranger sux big time...my lab could have written it.