Reset Check Engine light

A year might be nice.... the surest way to reset the check engine light is to fix whatever turned it on..... otherwise you'll be resetting the light over and over and over until the proble is fixed. Besides, whatever turned the CEL on may be a harbinger of accelerated engine wear or damage, needless (and expensive fuel consumption) and it most likely isn't doing too much for the air we breathe.....

To answer your question, yes, there is a way to turn off *most* CELs without a scan tool...

Jim Warman snipped-for-privacy@telusplanet.net

what (if any) are the likely causes of the CEL on a 1995 Explorer XLT that comes on occassionally? usually on long highway trips.

Best bet is to scan for code(s).... could be fuel trims working their way to their limit, catalyst efficiency monitor, EGR problems or a host of others I haven't even considered. It's a lot like trying to fix a PC but not being allowed to turn it on first..... DTCs are important clues that tell us where to start looking. Without them, we might be trying to fix something that isn't broken.

Jim Warman snipped-for-privacy@telusplanet.net

Is there any place I can take my 95 Explorer to get a readout of the scan codes? or can I build a cable and hook it up to my computer and read them myself? (preferably a cheap / free method :)

Many auto parts stores offer free code reading.... get the exact code and post it to the NG before you buy any parts.... Some codes show the direct cause while other codes are merely symptoms and it can often be difficult to tell the difference.

There are many hand held code readers in the $30 - $40 range... if you're after something a little more upscale, check out

Unfortunately, there is nothing cheap about owning a modern automobile leaving us with only two possibilities.... spending our money wisely or wasting it. I would recommend biting the bullet and getting into a scan tool with a few capabilities... software upgradable, ability to communicate with Ford proprietary modules (ABS, GEM et al), ability to monitor PIDs (Parameter Indicator Data) and, if possible, the ability to communicate with the new CAN networks. If you have some good friends that also fix their own cars, you might consider investing in one as a group.

Jim Warman snipped-for-privacy@telusplanet.net

The guy at Autozone used a scan tool and found the CEL came on due to a large vacuum leak. He could not narrow it down any better. The vehicle shows no signs of drivability problems and I can not hear a vacuum leak. Any ideas what it could be?

Pretty nifty scan tool to be able to do that...... not even our dedicated Foed scanners can identify a vacuum leak...... why not post the codes and let someone other than a partsmonger help you figure it out?

FWIW, while there are many things that the PCM can accurately diagnose, base engine concerns are not amongst them...

Jim Warman snipped-for-privacy@telusplanet.net

One way to reset the Engine light on is to disconnect the battery for about 10 secs. On restart you vehicle will run rough as the computer retunes itself. This is not the best way as the problem will only come back. Best way go AutoZone and have them do the scan (free) and try to isolate the problem from there..

The guy at Autozone was probably referring to an EVAP leak. To the best of my knowledge, that's the only malfunction with a fault code that has the word "leak" in the description. The most common reason for setting EVAP leak fault codes is a loose gas cap.

A vacuum leak usually shows up as a fuel system lean malfunction: P0171. However, this fault code could also be set for a myraid of other reasons as well.

tom

Never thought about theEVAP.... for some reason we rarely see problems with the evaporative emissions system here in the frozen north...

Jim Warman snipped-for-privacy@telusplanet.net