My wife drives a '97 ford explorer. It has the low-output 4.0 L V6. Last evening while driving in moderate city trafic it stalled.
Details:
one of the hottest days in 2 yrs (101).
AC on.
16,000 mi., never been out of metro Denver
mostly short trips.
Premium Gas.
7 mo. out of warranty
After allowing the vehicle to cool (while I was driving to her location), we started the vehicle and it ran without stalling for about 5 miles. At this point we turned on the AC. Within about 2 mi. it stalled again. I pulled off the road and restarted the engine. It started and would run at normal idle speed for about 30 seconds, then the idle would drop to near stalling for about 10 seconds, then recover. While we observing this cycle, we turned off the AC and made no attempts to drive. The frequecy and duration of the low idle speed decreased, so we continued and by the time we got home it seemed to be running fine. By then the outside temp had dropped by about 10-15 drgrees and the AC had been off for about 15 min.

Any ideas?

 

Did you happen to notice the engine temp during all your troubles ? Normal , higher ? I suspect the A/C is not the problem but is adding an extra load to the engine only making whatever is wrong worse . There are so many possibilities that unless one can diagnose the problem in person any suggestion is merely speculation . When was your Explorer last serviced ? Since it isnt driven a lot I am kinda leaning toward a fuel related problem . Had you recently refueled when the problem began ? How often is the vehicle driven and the usual daily mileage ? Let us know .
Paul

 

Paul,
As usual, the problem is never very simple. You are quite accurate about the need for more particulars concerning this problem. Here goes with some more info. My wife had just filled the tank with Amoco Supreme gas. The vehicle is driven about 5 mi./day and sees very little freeway use. About once a month it is driven to the airport (60 mi round trip). My son, who is enrolled in a apprenticeship program at a Toyota dealership through his tech school, helped me get the vehicle home. All gauges werer normal. There was no "check engine" light associated with these stalls, so no codes were generated. The next day my son went to our Ford dealership and asked if this was a recurring problem. The tech he talked to, said yes and the problem was probably related to the mass air flow control, but could be a air cleaner or fuel filter problem also. We replaced the filter with a K&N and also the fuel filter (both original). Tomorrow we will take it to the dealership for tests on the mass air flow control. I will report on the diagnosis at that time. I will also negoiate the cost for this repair as it is so recently out of warranty and so few miles.
eds.

 

Ive seen and heard tell of a few MAF Sensor problems with the Explorers but usually on older models which is why I didnt really suspect yours . Its possible yours may only be contaminated or it may be on the way out for good , very hard to tell sometimes with electronics . The K&N filter is a good idea , Ive had one in my truck for yrs and it works great . Also , Id say your engine would run just fine on a lower octane fuel , unless Ford recommends you run a higher octane in that engine ?
Paul

 

Paul,
This pertains to the original problem actually. My wife had a brief episode of this same problem earlier this spring. On a return trip from the airport, she had the same or very similar problem, that is the vehicle stalled but she was able to restart the vehicle almost immediatly. I reasoned the injectors might be dirty due to her driving habits, i.e. short trips and low miles/year. For this reason I recommended the Amoco Supreme, as I had heard this gas had some heavy detergents fomulated to clean fuel injectors. She noticed immediate results in the form of increased milage and performance. We intended to switch to the middle grade (half the detergents, according to my source) at some point, but to my knowledge she had not made this switch.

eds

 

Eds ,
Your Explorer has Deposit Resistant Injectors which means unless the engine is severly carboned or sludged I doubt the injectors would be dirty enough to cause the stalling . More than likley with short trip driving carbon buildup on the tops of the pistons coupled with the lean mixtures of todays engines may be partly to blame for the stalling ? If it runs better on the higher octane and you dont mind paying the extra cost continue its use .Engines that dont have time to remain at operating temps for extended times tend to suffer more from carbon buildup than engines that are run more often .
Paul

 

First thing to check is the Idle Speed Control.
Mine had a very similar symptom at 41K miles and
it was the ISC. Cost $40.00 at the dealer and took about 15 minutes to replace.

 

Well the jurys back. The dealership where we bought the vehicle has diagnosed the problem - bad fuel pump. Replacement cost in the range of $650. In light of the low milage and being only 7 months out of warranty, we asked the technician to look into the possibility of Ford or the dealership picking up some of the cost. She did and, sure enough the majority of the cost will NOT be paid by us. Our portion of the cost will be 20%. While this is VERY reasonable, I like to think this is what makes a dealership work. Along the same line, the car maker also is in this mix. We were asked if we had extended warranty. We answered no, I didn't believe in them. I believe extended warranties are for someone who needs a car, but really doesn't want to take responsibility for maintaining the vehicle. I expect the car to be of high enough quality and considering the cost, the type of care, etc. for our vehicles to last for a number of years (at least 10), without needing extensive or expensive repairs. This example has not changed my mind. We are very happy with the dealership, the technical staff, and of course Ford. They can all take some responsibility for a job weel done.

 

Eds ,
Im glad Ford got it fixed up for you . This is a good example of a customer working with a dealership . I know from experience some people come to the dealer with a combative attitude & that doesnt always go over so well . All vehicles need repairs & parts fail . You got a pretty good deal ...the dealer is basically not charging you the labor to R&R the fuel pump . Dealers are more willing to work with a customer that has taken reasonably good care of their vehicles vs someone that hasnt .
Paul

 

Last evening we got back our Explorer. The bad fuel pump was probably defective from the "get-go" as my wife says the vehicle is performing better than it ever has. The defective unit had an output of 19 PSI. I don't know what the standard is but the new one has an output of 35 PSI. The total bill was $79.33. This was the original estimate for diagnosis. The 20% percent figure quoted earlier was never mentioned. This is the first I have been in a position where I was at the mercy of a dealership. I have heard numerous horror stories from just about every make/dealership. I was very pleased and would like to thank Ford, and in particular the John Elway Ford dealership here in Metro Denver. I have tried to find an e-mail for this dealership but have been unsuccessful to this point. I will continue to look or, as a last resort use "snail mail" for the well deserved "atta boy".

 

Maybe the Slow White Bronco / OJ jokes has John Elway Ford doing an extra good job ? Just glad you got your Explorer running the way it should be . If you want to send praise , make sure the person that did the actual work gets the note . Often times the techs get the short end even though they have worked hard to solve a problem .
Paul