Is there a procedure that I need to do after I hook back up my battery? ('94 Ranger 4.0) I was looking in a manual for a '04 Explorer and it said to let the engine warm up, idle for one minute. Turn on A/C for one minute, then drive. In the past I just jumped in my cold truck and took off. I couldn't find anything in my '04 manual or in the Haynes book. Thanks for your advice!

Bob

 

Let it idle for about 3 minutes before driving is all.

 

Wonderful. Thank you CowboyBilly9Mile.

 

The reason it says to do all that is to reset the OBDII trip monitors.

There are several monitors that keep track of misfires, O2 operation, O2 heater operation, evaporative fuel system, EGR operation, etc. etc...

If you had to run an emissions test, say... tomorrow... you'd have to follow certain procedures in order for the vehicle to run the proper tests to enable these monitors. The worst as an automotive professional is having to get the vehicle repaired and prepped to pass the emissions test - sometimes it takes an entire day of driving and cooling off in order to get all these monitors set.

If you have no immediate need to do any diagnostic or emission testing, then don't worry about it. The truck may run a little goofy the first few miles, but eventually it will run the tests it needs to run during normal driving, it just takes a lot longer if you don't follow the proper procedures.

If you're truly concerned about it, do a search for "OBDII drive cycles".

Good luck

 

Ummmmmm...........a 94 uses EEC-IV, not OBDII.

 

In the case of a 94, just drive.

The tranny is vacuum operated and the engine will straighten itself--if need be--in short order.

 

If you have an auto tranny you may find the following routine useful, I have!!!!

After a battery disconnect, my 94 Taurus owners manual calls for me to turn all the electricals off.

Then begining with a COLD start, in "P" or "N" let the engine idle down, until it stabilizes.

Don't shift into any gears until the engine idles down & it's speed stabilizes.

Once the cold idle speed in "P" or "N" slows & stabilizes, THEN, SLOWLY shift into each gear, including Reverse & Neutral & STOP at each gear selection long enough, so you feel the tranny engage & disengage & the engine speed adjusts, so the computer has time to react & learn to reset the engines idle speed, at each gear position.

Then let it idle, in "N" or "P" undisturbed, until fully wamed up & then go through the above gear selection again, SLOWLY shifting into all gears, such that the computer has time to react & adjust & thereby learn the correct cold & warm, engine idle speed, at each gear selection.

Then your good to go.

This routine takes a little time, maybe 15 minutes, but doing it this way I've never had any of my Ford rides act up, while driving, after a battery disconnect.
All up & down shifts & shift points were normal, all engine speeds were normal & driveability was good.

As has been said, starting & driving it right away, after disconnecting the battery, will take the computer a little longer to learn it's correct cold & warm idle speed & it's emissions info & it might act up a little for a short time, or for a complete cold/warm drive cycle or two, but eventually it'll relearn.

After a battery disconnect, I take the time to use this routine on my 99 4.0L Ranger too, with good results.

You can save all your presets, for the clock, radio, ect, even the above computer memory info, by rigging a 9 volt battery with a 12 volt adapter & plugging it into the 12 volt power point outlet, or cigar lighter outlet, while you have the battery cables off.

Just have the negative battery cable clamp loosened, so you can remove it right away, after plugging the 9 volt battery in, as the vehicles 12 volt battery, will try to charge the 9 volt one & it might not like that, if left that way too long!!!!

Of course you could rig a diode in series with one of the 9 volt batteries leads, to prevent that reverse current flow from happening.

If you do this 9 volt battery memory retention thing,, you'll have to take care that the B+ battey cable, or other B+ power lead, doesn't touch the vehicles body, or it'll short the 9 volt battery to ground & discharge it!!!!

You'll also have to disable any courtesy lights, like dome, under hood, glove box, ect, before plugging the 9 volt memory saver in, so they'll not drain the 9 vot battery, or all this will be for naught!!!! lol

Just some more thoughts to wrestle with!!!!! lol

 

I cleaned the MAF the other day and had my battery cable off for 20 mins..... I just jotted down my radio settings before unhooking the battery & when I was done cleaning my MAF I hooked up the battery reprogrammed my radio & dove off... Had no effect at all on the running of my 1999 Ranger 4.0L....