Feed up with my 94 XLT 4.0L Explorer 69,000 miles

[Rjj]

Feeeeeeed UP with my 94 XLT 4.0L Explorer 69,000 miles

Always very poor gas mileage, knocks bad while going on the highway, engine light goes ON while driving on hwy...(usually after I let up on the gas), and cruise control is out (hoses plugged). This vehicle was under warranty when I purchased it and Ford miserably failed to fix the engine issues (poor gas mileage, slight knocking) and then 800 miles after the warranty expired...the front rotors were found to be destroyed, had to replace everything!

Ford told me the "engine wasn't getting upto temp", so they installed a higher temp thermostat. I just had the original one put back in. I believe the temp-sensor or something like that could be misreporting...hence the bad gas mileage (11mpg in the city).

I once had the plugs changed and that seemed to help for a while. I don't know if I want to spend anymore money on this lemon. The diagnostics are costly and no garage has figured it out to date. How can I diagnose the problem myself? I have a technical background. What do you recommend? I would appreciate any and all help!

SpeedSter240EFI
Rj

 

[TPLYNCH]

Buy a code reader and read the codes from the Check Engine Light. May help narrow down your problems. Have you cleaned your Mass Air Sensor? May have a bad O2 sensor too.

 

[Rjj]

Just decided to tackle it myself ...

Please supply more details on your recommendation. Where to buy a code reader and how do you clean the other thing mentioned?

Whatever was bad or wrong has been that way from the start. The engine has always gotten very poor gas mileage and performance. The fact that Ford (numerous visits) and several other shops have failed to fix the problem leads me to believe it is something tricky or complicated. It doesn't burn oil, just lots and lots of gas!

I'm looking at a Durango V8. It will get better gas mileage than this V6 Ford. Know anyone that wants to buy my Explorer?

SpeedSter240EFI
Rj

 

[JDraper]

You can get the code reader for about $20-30 from Wal Mart or an Autozone. As for the Durango getting better mileage, I test drove a couple with the 318 V8, and they average about 12-14 mpg. Most Explorer V6's will do much better than that when in good condition. My old '92 Sport (had a 5 speed stick) got 18 mpg city and 20 highway. My '01 XLS gets about 16 city and 19 highway (auto tranny)

It sounds like you might have an issue with your MAF sensor or your O2 sensors like TPLynch said. Use the search button on top to look for threads on it. I know there have been several on the poor gas mileage, and it can usually be traced back to one of the two items above.

 

[Rjj]

I picked up the Actron Code Scanner

I tried to use it last night in the cold and dark. It wasn't a very controlled test. I will perform the tests more accurately today. The testing is very simple the interpretation is another LOL.

The first test indicated 15 and 18 (I think). The next time(s) it only flashed 111. I am a newbie to this code thing, but I would conclude the memory is not working properly. Isn't the CODE(s) suppose to remain static until cleared?

My Ford is senile!!!

SpeedSter240EFI
Rj

 

[S. Allen]

I'd look elsewhere ... not at the Durrango!

My brother owned two Explorers, a 91 Sport and a 95 XLT and he traded his 95 for a 99 Durrango in 1999.

That has been the biggest piece of junk we have ever seen!

He has only 28,000 miles on it and things have gone out on the Durrango in 28K miles that have never gone out on his two Explorers or on my wife's 95 Explorer or my 91 Ranger. Stupid things, like the rear door hatch not opening and the power steering pump. My Ranger's PS pump went out after 9 years and 135K miles. My wife's Explorer still has the original PS pump after 6 years and 130K miles...and the rear hatch is TWICE as old and has been opened TWICE as long...I guarantee it.

He has had other troubles, like an auto tranny that wouldn't shift past second gear (wierd...but I experienced it myself!). Dodge dealership fixed it under warranty, but could not explain what happened. The Durrango had maybe 15K miles on it.

Again, for comparison, our Ex went 115K before tranny troubles...the Ranger went about 135K before tranny troubles. We report...you decide.

The Durrango is a typical Dodge product. It LOOKS attractive...it has a powerful engine and is big and all, but is VERY poorly built and has HORRIBLE reliability record. A v-8 is cool, but if it is not reliable...who cares about the power?

My brother is more than sorry he bought that Durrango and is replacing it with a 4-Runner next spring. Say what you want about the 4-Runner, but reliable is one of its strong points and he is sick of the cheapness and unreliability of the Durrango.

As for your Explorer: theres tons of things you need to check/replace to fix poor mileage. Our 95 is no peach on gas mileage, but its better than 11mpg.

Try cleaning the throttle body, replacing the plugs, cleaning the IAC module, changing the fuel filter and going a little easier on the gas pedal. You should get around 15-19 mpg if you drive it half way sane.

The Explorer is not perfect (don't you love that front end?...can you keep it aligned for long?), but its miles above the prroly built Dodge Durrango.

If you want a replacement for your Explorer, don't like the new Explorer (I don't either!) and want to buy American, the TrailBlazer looks awful good. 270hp V-6 and a much better ride than the old S-10 Blazer. I know...its a Chevy, but it has better quality than ANY Dodge product...and more HP from its V-6 than the Dodge V-8 (go figure!). Other than that, the 240HP Nissan Pathfinder looks awful tempting...doesn't it? Pathfinder still has more HP than the V-8 Durrango...and will stay away from the shop longer than the ratty Dodge will...I am sure of it!

-SA

-SA

 

[expobronc]

as for the pinging... hmm does your ex start right up? idle alright? any hesitation?? im thinking timing. but since there is no distributor on the 4.0 to simply re-clock, it may be the timing sensor thingy on the flywheel. that would certainly cause high rpm pinging. might cause the bad gas mileage too, does your exhaust smell rich? not sure the code reader would pick that one up. maybe the new plugs that you mentioned were gapped diferently and thats why they may have helped a little. in theory a larger gap would take longer to fire, not very much mind you but you only said it helped a little. dont give up on the ex man!! i have a 92 4-door with a 5-speed and 160k miles. i still get 20mpg on the highway and i havent changed the plugs wires, fuel filter, in over 50k miles. starts every damn mourning and still gets a second gear scratch when i ask it to.


but if you have to replace it i would buy a grand cheerokeet or an xterra, the new one with the blower that is one TIGHT rig!!!

 

[Rjj]

A few things I left out...

Last week Thursday, I started hearing a noise like the water pump was shot! It was real bad so I canceled a busines trip on Friday and took it to the shop. They needed to contact me but I was out. They found the belt tensioner was in bad shape. Less costly than a water pump repair but they wanted to inform me of the repairs before they completed them. Seeing how they were busy and they couldn't contact me, they needed the stall for other vehicles. They decided to back it out and wait for my contact...as they were backing out the belt tensioner broke completely off and the engine died.

Needless to say, I was very lucky to cancel my trip and bring it to the shop. It runs much better since the belt tensioner was replaced but the Knock/ping reaching highway speeds is still there, as well as the poor mileage. I never smell oil, nor does it burn oil, the exhaust is never black.

With the recent bout of repair costs, I am getting sick of dumping money into this Ford. I also had a 1991 Ford Explorer...it was great but I was getting worried about the mileage (well over 100K). Although, that babie ran great and got excellent gas mileage! That's why I purchased another one! This 94 doesn't compare at all! It sucks and has always suckED!!!

I haven't had time to play with the Code Scanner. Hoping to doo it soon. Perhaps I can fix the dam thing and it will perform as my 91 did! If I doo trade-in the Explorer, the next vehicle must be able to tow my 1800 lb plus trailer SeaDoo SpeedSter 240EFI jetboat!

SpeedSter240EFI
Rj

 

[Rjj]

Few more symptoms...

It nearly always starts on the first try. Lately, it has taken two attempts when cold.

Does anyone have a drawing of the 4.0L so I can locate various sensors etc...? I purchased a new engine temp sensor and I would like to install it. Any advice?

Years ago I drove 69 and 70 Mustangs. The tranny's had a Modulator Value which sometimes went bad which in turn made the tranny perform poorly. Does the 94 4.0L tranny have the same type device that could be changed? My Explorer has never shifted "good", especially while passing on the highway.

SpeedSter240EFI
Rj

 

[TPLYNCH]

Yes, I believe the "94 still had the modulator. As for your pinging/gas milage problems, another cause of pinging is carbon buildup. You can run a can of carbon cleaner thru and see if that helps. Also, the Fuel Pressure Regulator is notorious for going bad. It will dump too much fuel, causing lower gas milage. Another consequece of that is bad O2 sensors. Depending on what codes you pull, and after 7 plus years, I'd probably clean/replace the MAS, check/replace the FPR, try to blow out the carbon buildup and check/replace the O2's.

 

[oceanworker]

Are you sure it only has 69,000 miles.. Sounds more like 169,000. Or else it must have been rode hard and put away wet. Many things can cause poor mileage. Probably the o2 sensors or fuel pressure regulator is your likely cause. What are your codes. Get them with key on-engine off and also at idle.

 

[BUCHVILLEMAN]

sounds like it could be a problem with the EDIS. a code reader could tell you the problem but you might want to take it to a private machanic with a diagnostic machien and he can tell you better in my opinion than a dealer.

 

[Tekeman]

loaded durango, $30k ?

A good friend lost the tranny or maybe the rear differential, with 20 some thousand miles on it, right up from my house when where heading out with our jet skis. Clunk.....and a stream of fluid frim the pumpkin. Made for a rather unhappy Sunday. After Dodge fixed it he traded it on a new Grand Cherokee.

 

[BUCHVILLEMAN]

my dad has a GC limited and he has had nothign but problems with it. new radiator, 2k in ac work, alternator, fuel injectors, cv joint, the list goes on. and as fast as everyone says they are i am not that overly impressed with the performance. i thought i liked durangoes at first but not anymore. they seem to be a lame attempt at cashing in on the midsized SUV market with littel thought. dont get me wrong i hav seen them on 33"s and they can get around on the beach pretty good.

i love my XLT!

 

[Blaine122300]

Start cheap. Clean everything first. Spray the Mass Airflow sensor with some carb cleaner. Run some injector cleaner through. There is a thread on how to clean the MAF Sensor. try it out.

 

[Rjj]

Codes I found

KOEO = 186

KOER = 538

Is there a diagram of the 4.0L somewhere so I can find the various sensors? Also, where is the Mass air sensor? How do I clean it?

Yesterday, I must have managed to clear the codes because I kept recording 111 111 111. I drove 75 miles today. The first 15 minutes, the engine ran great, then it started knocking again and then the engine light came ON/OFF while driving down the highway.

What doo you recommend next?
SpeedSter240EFI
Rj

 

[JDraper]

The Mass Air sensor is between the airbox and the air intake hose. It's bolted to the back of the airbox. As for your codes. My Haynes manual (suggest you get one. They have plenty of good info in them. Costs about 15-20 bucks) has the following:

186 code is listed as "Injector pulse width higher than expected" I have NO clue what that means unless it's an electronic feedback pulse from the fuel injectors.

538 Code is listed as "insufficient change in RPM/operator error in Dynamic Response check". I think this means you didn't rev the engine high enough to complete the test.

The Haynes manual has a lot of good info on how to run the tests to get correct code readings, as well as TONS of info on the truck.

 

[Bill MacLeod]

Spark knock can be caused by several things. Inoperative EGR (California model only), engine overheating, overheated air (intake air), spark plugs, MAF, IAC etc.
I had chased the problem for along time and the cause was contaimination of the #5 plug from the intake manifold leaking coolant into the cylinder.
Clean the mas with contact cleaner, the throttle body with sensor safe cleaner and the IAC valve with carb cleaner.
If you have a Digital Multimeter here are some reference voltages to check.
MAF - hot idle - 0.6 to 0.7 dcv
30 MPH - 1.0 to 1.4 "
60 " - 1.5 to 2.0 "
ECT - hot idle - 0.5 to 0.7 dcv
30 "
60 "
IAT - hot idle - 0.7 to 2.8 dcv
30 "
60 "
TPS - hot - 0.8 to 0.9 dcv
30 - 1.0 to 1.2
60 - 1.2 to 1.5

Inj. pulse width
hot - 3.3 to 3.6 dcv
30 - 1.0 to 1.2
60 - 1.2 to 1.5

 

[Dr. Ford]

Ping/Knock...

Retorque the intake manifold.
92-94 were notorious years for bad intake gaskets!
Usually torquing intake is ALL taht it takes!
#5 cyl. is usually the culprit.
I've saved MANY Explorer owners BIG $ (and myself) with this fix.
Seems everybody goes for the expensive stuff first.
Believe me on this one.

Try it.
You'll like it.
Oil in intake charge = higher compression due to denser charge. That and carbon build up in leaking cylinder.
Do search of posts for "ping intake" and you will find LOTS of previous posts.

Dr. Ford

 

[Iggy flywheel]

give it some love

I think Bill and Dr. Ford are on to your problem. I have same problem change plugs gas milage is good 17 miles then it droppes over time couple of months.
I need to check the manifold bolts but mine pings too at highway.
The chevron injector cleaner helps.
Check the voltage on the MAF mine is out of specs according to Hayes manual get one........... I think this is what is causing my poor milage EX's have a lot of these go out. Ford has not changed the design. Iam thinking of going with a aftermarket MAF. I would change the O2 sensors need to change them with your milage. I would also clean the plenum when u have it off to torque the manifold bolts. Clean the throtle body 2.