Help! Second time this has happened...driving in a raging snow storm in 4WD, the check engine light repeatedly turned on for a minute, then off for a minute, etc...on my '94 4.0 XLT. (67K miles) It seemed to be running fine. The last time it happened was about 3 months ago, same conditions. Any ideas??

I had a problem with a check engine light on Christmas. I started looking at the Temp gauge the Check engine light was only on when the thermostat was closed and the engine started getting warmer as soon as it opened the light went off. I changed out the engine temp sensor every thing has been fine since...



------------------
Kris Guilbeaux
--
http://www.tisd.net/~guilbeau/explorer.html

I recently had a similiar problem with my '91 XLT (83K). However, I was traveling from low desert altitude to higher altitude pine tree country. Once at "altitude" the check engine light would intermittantly come on and go off, rather frequently for about an hour (apprx. every 10 minutes). Then as time progressed, at altitude, it would come on less frequently and stay on for shorter durations. Within about 3 hrs. It stopped coming on all together and everything seemed fine. Admittedly, I'm no mechanic, I assumed the light coming on was do to the air-mixture and that the engine was running to rich. Eventually, when the engine "learned" the new environment, and adjusted the mixture (automatically ?) the problem went away. Maybe the automatic sensing/adjusting is a little slow/sticky because of build up of "gunk" over the years? Does this make any sense, or am I deluding myself?

------------------

I've had a 97 sport for about a month now and it's been back to the shop 3 times because of the check engine light. The guy at the shop(Ford dealer), says it has something to do with the emissions system. They've replace the vapor management vavle but the light came back on. It's in the shop right now. I'll let you know what they come up with next.

Kris -- thanks for your reply. Now that I think about it, the temp gauge was running a bit higher than normal. Usually it barely registers at all, this time it actually got to the "N" in the word "NORMAL". I'll keep an eye on the temp, and look into a new temp. sensor. Thanks again for the help!

Make sure that the thermostat is working correct, if you have not changed it since 94, its time. Also clean that MAS. WARNING-WARNING-WARNING----DO NOT spill antifreeze down the street. Its a 750.00 fine in Phoenix Ariz.

I also have had the problem of the Check Engine light coming on. It happened twice in exactly the same conditions.

2 Weekends in a row, I drove up to Tahoe. At about 5,000 ft. in altitude, after 3 hours of driving, and the last 1/2 hour in the mountains driving pretty aggressively, the light came on for about 10 minutes. It went off and then never came on the rest of the weekend.

All of the gauges were very normal, and if anything, the temp gauge seemed to be lower than normal. Is there anything else that ought to be checked other than those points mentioned in the above string?

It is disconcerting to see that light on! http://www.4x4central.com/ubb/frown.gif

Pete

1) I would recommend that you guys go get one of those $29.00 code scanners and plug it in the truck to see what the trouble code is. Even though the 'Check Engine' light goes off, the EEC (computer) will store any codes that appear and are then self-cleared due to the situation that caused the code having 'fixed itself'. The stored code will tell you what's going on, or at least it's a start as to what's going on.

2) If you haven't changed your thermostat, CHANGE IT NOW! Explorers are highly intolerant of stuck thermostats, especially ones that stick closed and cause overheating. There was a horror story on the old message board of an Explorer that was less than 2,000 miles out of the 50k powertrain warranty. She had just bought the truck from a 'reputable' Ford dealer. Well, the thermostat stuck, causing overheating. At least one head cracked, even before she got to the shoulder of the road, and now she has a new engine, all at her expense. There is no delay between the point when the gauge says HOT and engine damage time. FoMoCo basically told her to go fly a kite.

If you want to really check all the systems, go to your local parts store and buy a code scanner. I paid $30.00 for mine. There a piece of cake to use and will check all the systems and "beep" out any codes it finds. It saved me a ton of cash. My check engine light came on and my 94 sport was running fine (just eating a little more gas). The scanner told me where to look. I did the trouble shooting and fixed the problem.

Good Luck

Darin

Ok what does trouble code 332 mean? by the way who the hell needs a scanner just go to the box where the white wire is ( at least its white on my 94 X) and connect a wire to it and to the ground on the battery go in your truck and watch the check engine light do its thing it will start flashing 1 1 1 and repeat itself 1 1 1 to show you its testing then pay attention cause here comes your codes after the first set ( if there are more than one it will flash 2 times to let you know ( I think dont hold me to this ) that the second set of codes is being shown so what the hey does 332 mean? and where can we get all the codes and thier meaning?

http://www.explorerforum.com/forums/showthread.php?s=&threadid=49956

I've run into this also. But you can not always go by the codes, it may be a problem associated with the code. A 332 is a problem with the EGR valve. But I have replaced the EGR valve and still get the same code. I am going to replace the PFE sensor(Presseure Feedback EGR) shortly to see if that will remedy the CEL. PFE is used on 94 and earlier models. DPFE is used on 95 and later models.

so where is the PFE? i forgot to tell you that i also had at the same time my solenoid for the charcoal canister go dead on me so i replaced that ( trouble code 565) Could the two have anything to do with each other? That code no longer shows up. My EGR valve looks kinda dead its rusted as all get out It is expensive and do you just replace the valve and NOT the whole tube assembly?

Tim describes its location in the thread I attached above. The EGR Valve runs about $35.00. The PFE Sensor runs about $75.00. If you change out the EGR, you will more than likely need to take of a small plate less than 1/4 inch, that is held on by a hexhead bolt and place the plate on the new EGR. BE VERY careful when remove the plate, as it willcrack and break if not careful. Mine did. Use a set of pliers and twist it side to side until it loosens enough to remove.

Thanks I didnt see the thread Ill take a crack at it on Sat morning Peter:)

if you want to know the meaning of codes, go here:
http://www.therangerstation.com/3digitcodes.html