rough idle, overfueling, no codes - Ford Explorer Ranger Enthusiasts "Serious Explorations"®

ford12 · 12-09-2008, 06:08 PM

I have a 93 ford explorer. The engine light comes on and off. It idles rough gets horrible gas mileage and no power. I took it to the only shop in town to have codes checked, three test later no codes. I cleaned the MAF with MAF cleaner. It still runs like crap. I'm sure it is over fueling for some reason. I'm getting alot of smoke, and exhaust smells like gas. any ideas. MY only idea left involves a cliff.

*Sams01XplrSprt* · 12-09-2008, 06:41 PM

welcome ford

*fiftyfordfloored* · 12-09-2008, 07:00 PM

Welcome!

Sounds like it could be the ECT (Engine Coolent Temprature) sensor. The one the computer uses, not the for the gauge. If that's not working or it's giving false readings, it can cause the computer to dump more fuel and run terribly. That's exactly what happened to my truck and no one could figure it out.

I'd recommend changing it anyway if you have like 150K on your truck; don't get the crappy plastic threaded one, get the brass threaded one... even though it costs like five bucks more...

ford12 · 12-09-2008, 08:01 PM

could you give me more information on the ect sensor. I called napa the guy could not figure out what I was talking about. was it an explorer you had problems with. Could you tell me where it is located on the engine. thank you

ERUSH97XLT · 12-09-2008, 08:10 PM

Hello!

I had the same problem on my 93 ranger (4.0L OHV). Same poor idle and running conditions. I cleaned the MAF AND replaced the ECT sensor. No luck. So it turns out, even though the MAF was sparkly clean, it wasn't sending the proper air information the the computer. The computer thought more air was entering the engine, hence the insanely rich mixture.

IMO, if its not the ECT, change the MAF. What do others think?

Good Luck!

ERUSH

*fiftyfordfloored* · 12-09-2008, 11:43 PM

Quote:

Originally Posted by ERUSH97XLT

Hello!

I had the same problem on my 93 ranger (4.0L OHV). Same poor idle and running conditions. I cleaned the MAF AND replaced the ECT sensor. No luck. So it turns out, even though the MAF was sparkly clean, it wasn't sending the proper air information the the computer. The computer thought more air was entering the engine, hence the insanely rich mixture.

IMO, if its not the ECT, change the MAF. What do others think?

Good Luck!

ERUSH

I think that's about dead on ERUSH. My problems were with a '92 Explorer.

The ECT sensor is on the front-most part of the lower intake manifold (coolant crossover), under the throttle body:

You can test it with a multimeter using the following table as reference:

My personal feeling, if your truck has 150K or more on the clock, replace all the sensors (including the O2 sensor) because they do wear out and become inaccurate.

I changed the ECT with NAPA part number DEMTS10001. That part is made by Delphi and it's good stuff. The truck behaved much better and stopped almost all of what you are describing above, except it still ran slightly rich. After I replaced the ECT it popped a new code for the MAF sensor being out of range. After a week or so, of popping that code and resetting the computer, I changed the MAF sensor and it ran like a brand new truck.

If you do decide to change the MAF too, go with the remanufactured part, XTP49504 (NAPA #). It's a lot cheaper, and it works just as good, but you will need to bring your old MAF assembly with you for the core, or they'll charge you extra. You get the whole assembly, nice shiny new housing included.

boggs1227 · 12-10-2008, 12:01 AM

hey... how come your iac has a fitting on it ?

*fiftyfordfloored* · 12-10-2008, 12:09 AM

Not my truck, that's just a generic picture of an OHV... '96 I believe... I'm just pointing out the location of the ECT that's all.

boggs1227 · 12-10-2008, 12:25 AM

oh ok .... iwas wandering about that .

MrShorty · 12-10-2008, 01:05 AM

Personally, before I replaced anything, I'd do some basic diagnostics. I'd pull codes myself, even though the shop they got no codes. EEC-IV codes only take a few minutes to pull, and the test can be performed with nothing fancier than a paper clip (Check out our instructional threads in the Under the Hood forum and the EEC-IV forum). As rough as you say it's running, they should have at least got a KOER 411 or 412 (though those aren't very useful codes if they are the only ones that come up).

I would also pull the vacuum line to the FPR and check for gas (=bad FPR) and put a fuel pressure gauge on it and see if fuel delivery was up to snuff.

*mikeinri* · 12-10-2008, 12:56 PM

1000% agree with Mr. Shorty, read the codes. If you get a CEL, you have a code (unless there's a computer problem and they're not being stored, but that's another story).

While I also think the ECT and especially MAF are suspect, blind part-swapping wastes lots of money, and gets extremely frustrating (not to mention time-consuming) when the parts you blindly replace don't actually fix the problem. For example, I have personally dealt with a MAF code that was actually caused by a broken electrical connector (after having the oil changed, of all things). If I had just replaced the MAF, the problem would still be there, and I would be out big money.

My personal experience differs from the others here, I have had terrible luck with anything other than genuine Ford parts for sensors.

Hope this helps.

Mike

ditchboy · 12-10-2008, 01:48 PM

Had A 91 sport that the fpr went on sounds like the same problem i had

**JDraper** · 12-10-2008, 04:47 PM

I'd agree on not just throwing parts at it. However, a bad fuel pressure regulator (FPR) will give you the same symptoms without a code. Easy to check too. If you find the fpr on the motor, it will have a vacuum line going to it. Pull the vacuum line and see if there's fuel present. If so, your FPR is bad. If not, go on to further diagnostics, including measuring the fuel pressure on the rail. It should be about 30-45 psi at idle with the vacuum hose attached, and 40-50 psi at idle with the vacuum hose detached. After sitting for 5 minutes (engine off), the fuel rail pressure should be 30-40 psi.

jvog · 12-10-2008, 07:09 PM

i have a 94 navajo and it gets like 14 mpg..is that average or bad? It doesnt idle rough but it runs extremely cool..like 1/4 -1/3 of the temp gauge most of the time.

ford12 · 12-13-2008, 09:51 AM

Thanks for all your help guys. I found a rebuilt MAF sensor and tried that. Now I can pull up to a stop light without the guy next to me thinking I want to race him. MY exp. would lunge forward it was running so bad. I still think that it is strange it didn't show a code. I can't believe the power difference it must have been going bad for awhile. I have 167 thousand on it must be something to the 150 k on those sensors. thanks again

ERUSH97XLT · 12-13-2008, 08:27 PM

Good work, ford!

Glad you found the solution!

As I said, that's what happened on my ol' Ranger. Except I got an old MAF sensor out of a junk yard for cheap and tested to see if indeed the MAF sensor went out. Once I found that to be the culprit, I bought and installed a rebuilt one. All my troubles went away, until I traded it for my Explorer.

ERUSH

doorsbydavid · 12-28-2008, 10:40 PM

Hello, I came home the other night with the family and forgot I needed to go back to the store. So I dropped the family off back out of the drive way and down to the stop sign and the engine stalls. I GOT A 1996 4.0 FORD EXPLORER and haven't had any real problems since replacing the motor over 1 year ago. I plug in the scanner to check for codes and had only the same codes that have been haunting me for a while nothing new.
well to make long story short I had to floor the throttle pedal to get it to crank and after it cranked I let off the pedal and it would idle but as soon as I put it in gear or give in gas in park it would go dead after getting it to crank a 3rd time I waiting to see if maybe it was flooded and burn out the extra fuel. by the way it smelled like it was running rich too. anyway it finally started running right, so I drove to the store got some gas just in case. well it was doing fine after that. next day went out to get a frosty at wendys and while waiting at the drive thru it starded running like I was hitting the gas and letting off over and over , up down. so I threw it in park and was fine, left and came back up the road and it died at red light. Same problem I had at the stop sign.
and that problem came about ever time I drove it the last 4 times intill I got mad. after doing so research I found that the etc engine tempature sensor might be bad. so I plug the scanner in and found the the computer thought that my engine coolant was -4 degrees well HAHAHA that's crazy it's 60 degrees outside. I fooled with it when it was acting up and played with the plug in and for some reason it was reading 160 degrees on my scanner so i tried to crank it and fired right up no problems so I left scanner pluged in and drove it around finally had the problem again check my tempature reading and sure enough it's was reading -35 degrees when it should have been 160 or higher same problem at stop sign intill the sensor started to read right again. then it fired right up no gas pedal pushed, just turning the key crabked it. I hope this help you out. P.s. sorry for the long wind but i had to say alot. Thanks Doorsbydavid

*Dre* · 01-25-2009, 02:36 PM

see, I need to look into that too... I'm working on a customer's "X" which runs rich and has no power. I have replaced the intake with all the sensors and EGR and still the same... will have to look into checking the FPR and ETC tomorrow... see I can't really check the temp sensor since the truck is a 95... no OBD II...

*fiftyfordfloored* · 01-25-2009, 04:12 PM

Quote:

Originally Posted by Dre

see, I need to look into that too... I'm working on a customer's "X" which runs rich and has no power. I have replaced the intake with all the sensors and EGR and still the same... will have to look into checking the FPR and ETC tomorrow... see I can't really check the temp sensor since the truck is a 95... no OBD II...

You can use a multimeter to check it. Refer to post #6 for the reading values...

justinexley3030 · 03-14-2009, 09:43 PM

You folks have been a big help been racking my brain all day thanks a million

12-09-2008, 06:08 PM	#1
ford12 Wannabe Elite Explorer montana 93 Join Date: Dec 2008 Posts: 3 Vehicle Specs	rough idle, overfueling, no codes I have a 93 ford explorer. The engine light comes on and off. It idles rough gets horrible gas mileage and no power. I took it to the only shop in town to have codes checked, three test later no codes. I cleaned the MAF with MAF cleaner. It still runs like crap. I'm sure it is over fueling for some reason. I'm getting alot of smoke, and exhaust smells like gas. any ideas. MY only idea left involves a cliff.

12-09-2008, 06:41 PM	#2
Sams01XplrSprt Southern Cali Explorer Newport Beach California & Bay Area California 2001 Sport 4x2 Join Date: Nov 2004 Posts: 11,623 Vehicle Specs	welcome ford __________________ 2001 Explorer Sport 4.0, Single in Dual Out 40 Series Flowmasters, Yellow Fogs, High Flow K&N Air Filter, Removed Silencer, Lowered Windshields and More mods coming soon 2007 Nissan Altima 2.5 S

12-09-2008, 07:00 PM	#3
fiftyfordfloored Exploder Super-Upper Lebanon, New Jersey 1992 Explorer 4x4 XLT Join Date: Jan 2007 Posts: 152 Vehicle Specs	Welcome! Sounds like it could be the ECT (Engine Coolent Temprature) sensor. The one the computer uses, not the for the gauge. If that's not working or it's giving false readings, it can cause the computer to dump more fuel and run terribly. That's exactly what happened to my truck and no one could figure it out. I'd recommend changing it anyway if you have like 150K on your truck; don't get the crappy plastic threaded one, get the brass threaded one... even though it costs like five bucks more... __________________ 1980 Ford F-100 Custom - Flareside 4x2, 300 I6 4v, C6, LSD 9" - 152K 1992 Ford Explorer - Sold 1994 Ford Taurus SHO - 163K - For Sale 1997 Ford F150 Lariat - Supercab Flareside 4x4, 5.4 / Auto - 254K

12-09-2008, 08:01 PM	#4
ford12 Wannabe Elite Explorer montana 93 Join Date: Dec 2008 Posts: 3 Vehicle Specs	ect could you give me more information on the ect sensor. I called napa the guy could not figure out what I was talking about. was it an explorer you had problems with. Could you tell me where it is located on the engine. thank you

12-10-2008, 12:01 AM	#7
boggs1227 Wannabe Elite Explorer Flowery Branch , Georgia, 1994 sport 2wd auto 2005 colorado 2wd 5spd Join Date: Feb 2008 Posts: 1,490 Vehicle Specs	hey... how come your iac has a fitting on it ? __________________ Scott .

12-09-2008, 08:10 PM	#5
ERUSH97XLT Wannabe Elite Explorer Join Date: Oct 2008 Posts: 71 Vehicle Specs	Hello! I had the same problem on my 93 ranger (4.0L OHV). Same poor idle and running conditions. I cleaned the MAF AND replaced the ECT sensor. No luck. So it turns out, even though the MAF was sparkly clean, it wasn't sending the proper air information the the computer. The computer thought more air was entering the engine, hence the insanely rich mixture. IMO, if its not the ECT, change the MAF. What do others think? Good Luck! ERUSH

12-10-2008, 12:09 AM	#8
fiftyfordfloored Exploder Super-Upper Lebanon, New Jersey 1992 Explorer 4x4 XLT Join Date: Jan 2007 Posts: 152 Vehicle Specs	Not my truck, that's just a generic picture of an OHV... '96 I believe... I'm just pointing out the location of the ECT that's all. __________________ 1980 Ford F-100 Custom - Flareside 4x2, 300 I6 4v, C6, LSD 9" - 152K 1992 Ford Explorer - Sold 1994 Ford Taurus SHO - 163K - For Sale 1997 Ford F150 Lariat - Supercab Flareside 4x4, 5.4 / Auto - 254K

12-10-2008, 12:25 AM	#9
boggs1227 Wannabe Elite Explorer Flowery Branch , Georgia, 1994 sport 2wd auto 2005 colorado 2wd 5spd Join Date: Feb 2008 Posts: 1,490 Vehicle Specs	oh ok .... iwas wandering about that . __________________ Scott .

12-10-2008, 01:05 AM	#10
MrShorty Wannabe Elite Explorer Spanish Fork, UT 92 XLT and '87 Bronco II Join Date: Dec 2001 Posts: 3,846 Vehicle Specs	Personally, before I replaced anything, I'd do some basic diagnostics. I'd pull codes myself, even though the shop they got no codes. EEC-IV codes only take a few minutes to pull, and the test can be performed with nothing fancier than a paper clip (Check out our instructional threads in the Under the Hood forum and the EEC-IV forum). As rough as you say it's running, they should have at least got a KOER 411 or 412 (though those aren't very useful codes if they are the only ones that come up). I would also pull the vacuum line to the FPR and check for gas (=bad FPR) and put a fuel pressure gauge on it and see if fuel delivery was up to snuff. __________________ Mr. Shorty 92 XLT 4x4 87 Bronco II XLT 4x4 '98 Chev K1500 Suburban SLT 4x4

12-10-2008, 12:56 PM	#11
mikeinri Elite Explorer 94 XLT, 04 Explorer Join Date: Jan 2007 Posts: 881 Vehicle Specs	1000% agree with Mr. Shorty, read the codes. If you get a CEL, you have a code (unless there's a computer problem and they're not being stored, but that's another story). While I also think the ECT and especially MAF are suspect, blind part-swapping wastes lots of money, and gets extremely frustrating (not to mention time-consuming) when the parts you blindly replace don't actually fix the problem. For example, I have personally dealt with a MAF code that was actually caused by a broken electrical connector (after having the oil changed, of all things). If I had just replaced the MAF, the problem would still be there, and I would be out big money. My personal experience differs from the others here, I have had terrible luck with anything other than genuine Ford parts for sensors. Hope this helps. Mike

12-10-2008, 01:48 PM	#12
ditchboy Wannabe Elite Explorer windber,PA 96xlt5.0 Join Date: Dec 2008 Posts: 3 Vehicle Specs	Had A 91 sport that the fpr went on sounds like the same problem i had

12-10-2008, 04:47 PM	#13
JDraper Stumblin' & Bumblin' McVeytown, PA '05 SCrew Join Date: Jan 2001 Posts: 12,127 Vehicle Specs	I'd agree on not just throwing parts at it. However, a bad fuel pressure regulator (FPR) will give you the same symptoms without a code. Easy to check too. If you find the fpr on the motor, it will have a vacuum line going to it. Pull the vacuum line and see if there's fuel present. If so, your FPR is bad. If not, go on to further diagnostics, including measuring the fuel pressure on the rail. It should be about 30-45 psi at idle with the vacuum hose attached, and 40-50 psi at idle with the vacuum hose detached. After sitting for 5 minutes (engine off), the fuel rail pressure should be 30-40 psi. __________________ Moderator..Home Improvement/Explorer 911 You took my breath away....and now I want it back.... '66 Mustang Coupe, '04 Mustang Mach 1, '05 F-150 Lariat SCrew, '08 Focus "Ex"plorer's: '92 Sport, '94 Sport, '01 XLS Our Crappy Website

12-10-2008, 07:09 PM	#14
jvog Wannabe Elite Explorer Join Date: Oct 2008 Posts: 5 Vehicle Specs	i have a 94 navajo and it gets like 14 mpg..is that average or bad? It doesnt idle rough but it runs extremely cool..like 1/4 -1/3 of the temp gauge most of the time.

12-13-2008, 09:51 AM	#15
ford12 Wannabe Elite Explorer montana 93 Join Date: Dec 2008 Posts: 3 Vehicle Specs	Maf Thanks for all your help guys. I found a rebuilt MAF sensor and tried that. Now I can pull up to a stop light without the guy next to me thinking I want to race him. MY exp. would lunge forward it was running so bad. I still think that it is strange it didn't show a code. I can't believe the power difference it must have been going bad for awhile. I have 167 thousand on it must be something to the 150 k on those sensors. thanks again

12-13-2008, 08:27 PM	#16
ERUSH97XLT Wannabe Elite Explorer Join Date: Oct 2008 Posts: 71 Vehicle Specs	Good work, ford! Glad you found the solution! As I said, that's what happened on my ol' Ranger. Except I got an old MAF sensor out of a junk yard for cheap and tested to see if indeed the MAF sensor went out. Once I found that to be the culprit, I bought and installed a rebuilt one. All my troubles went away, until I traded it for my Explorer. ERUSH

12-28-2008, 10:40 PM	#17
doorsbydavid Wannabe Elite Explorer georgia 1996 explorer xlt 4.0 v-6 Join Date: Dec 2008 Posts: 1 Vehicle Specs	Hello, I came home the other night with the family and forgot I needed to go back to the store. So I dropped the family off back out of the drive way and down to the stop sign and the engine stalls. I GOT A 1996 4.0 FORD EXPLORER and haven't had any real problems since replacing the motor over 1 year ago. I plug in the scanner to check for codes and had only the same codes that have been haunting me for a while nothing new. well to make long story short I had to floor the throttle pedal to get it to crank and after it cranked I let off the pedal and it would idle but as soon as I put it in gear or give in gas in park it would go dead after getting it to crank a 3rd time I waiting to see if maybe it was flooded and burn out the extra fuel. by the way it smelled like it was running rich too. anyway it finally started running right, so I drove to the store got some gas just in case. well it was doing fine after that. next day went out to get a frosty at wendys and while waiting at the drive thru it starded running like I was hitting the gas and letting off over and over , up down. so I threw it in park and was fine, left and came back up the road and it died at red light. Same problem I had at the stop sign. and that problem came about ever time I drove it the last 4 times intill I got mad. after doing so research I found that the etc engine tempature sensor might be bad. so I plug the scanner in and found the the computer thought that my engine coolant was -4 degrees well HAHAHA that's crazy it's 60 degrees outside. I fooled with it when it was acting up and played with the plug in and for some reason it was reading 160 degrees on my scanner so i tried to crank it and fired right up no problems so I left scanner pluged in and drove it around finally had the problem again check my tempature reading and sure enough it's was reading -35 degrees when it should have been 160 or higher same problem at stop sign intill the sensor started to read right again. then it fired right up no gas pedal pushed, just turning the key crabked it. I hope this help you out. P.s. sorry for the long wind but i had to say alot. Thanks Doorsbydavid

01-25-2009, 02:36 PM	#18
Dre Elite Explorer Poland 94 Limited Join Date: May 1999 Posts: 4,748 Vehicle Specs	see, I need to look into that too... I'm working on a customer's "X" which runs rich and has no power. I have replaced the intake with all the sensors and EGR and still the same... will have to look into checking the FPR and ETC tomorrow... see I can't really check the temp sensor since the truck is a 95... no OBD II... __________________ 94 Un-Limited - lifted and locked My Gallery

03-14-2009, 09:43 PM	#20
justinexley3030 Wannabe Elite Explorer Apex N.C. 1992 XLT Join Date: Mar 2009 Posts: 1 Vehicle Specs	Man Oh Man You folks have been a big help been racking my brain all day thanks a million