Automotive Forums

I HAVE A 1999 FORD RANGER XLT, 3.0L V6,4X4, AUTOMATIC WITH 150,000 MILES. MY CHECK ENGINE LIGHT CAME ON AND THE TROUBLE CODE THAT DISPLAYS IS P0176. THAT CODE IS A FLEXIBLE FUEL SENSOR CIRCUIT MALFUNCTION. DOES ANYONE KNOW WHAT THIS IS AND HOW TO FIX IT? I TRIED THE REPAIR SHOPS BUT THEY WERENT SURE WHAT THAT WAS BECAUSE THEY NEVER SAW IT BEFORE.IS IT A PART? A SYSTEM? WHAT. PLEASE HELP ME IF POSSIBLE.  

The flex fuel sensor is located inline on the left frame rail. It detects the alchohol content of the fuel and sends a signal to the pcm. It has 3 wires, one is 12v, one is ground and the third is the pcm signal. Check wiring, if ok sensor is likely bad.  

Hey Adam,

We have the same problem. I assume you got yours fixed? My mechanic said I neeed to buy a new flex-fuel box. Is that what you did?

If anyone has thoughts on where I can obtain one without having to pay for a ford issued one for $588 that would be great. Additionally, I wonder if there has been a recall for these flex-fuel systems.  It is frusterating that a feature I cannot even use in New England (ethanol) is causing me this much $ and time to get resolved.

Thanks in advance for any info/guidance...greatly appreciated.

Grace  

I had the same problem come up after we had some unusually cold weather; the real pisser was I had decided about 3 weeks prior that I was going to trade the vehicle in for a new one. Obviously I did not want to spend 500 bucks to replace a sensor on a vehicle I was about to trade-in.

After much searching this is what I was able to determine.
1) The part is integral to flex fuel vehicles you cannot just disconnect it, even though the sensor is not used unless you run ethanol.
2) As far as I can tell you can only get the part from a dealer.
3) Engine performance should not be affected by this sensor malfunctioning; unless running ethanol; this is implied by point 1.
4) The engine appears to poll this sensor, when the vehicle is first started and periodically while driving, it appears when the fuel level changes significantly (like when driving thru hills)
5) 2000 was the last year ford used that part (lucky me owning a 2000 model)

I inspected the part and it appears to be a simple solenoid, this makes sense given that ethanol has a different density than gasoline. All you need to know is the density of ethanol the density of gasoline and the density of something to compare with I'm unsure what that would be aside from some liquid that has a very low freezing point and a very high vapor pressure.  You just monitor the position of the solenoid and you can determine the density, once you know the density you can figure out the composition.
My first thought was what if something has gotten into the fuel and made it thru the fuel filter and has caused the solenoid to get stuck. I tapped the sensor w/ a screw driver, cleared the engine code and it ran for about 20 minutes before the light came back on.
Eventually I bought some inexpensive fuel system cleaner and added it to the tank and ran that thru (that was really just my 25 mile trip home from work). After letting it sit for the night I went out, cleared the codes and drive for a while. It eventually came back on. Finally I thought what if the computer has some sort of memory that I am unable to clear. I disconnected the battery and forced the engine to relearn everything.
Thus far the light has not come back on. My best guess is that the solenoid was in fact stuck and between the tapping and cleaner I was able to flush out whatever was gunking it up.
Hopefully, that helps others out there who are either currently trying to fix this problem or who will face this problem in the future.  

Hi, I hope you have some advice, or help for me. I ahve a 2000 ranger with flex fuel, that has been down for 2 months now, with a problem. I have the code of PO-0176 that comes up also. I know this part cost about $500-$600. I cannot afford this much. I can only drive the vehicle for about 25-30 miles, then I disconnect the battery terminal,and reset the computer. I cannot use this vehicle to go on the highway, it is not safe.The motor will just stop, it gets no fuel,and you roll to a stop.The first time this happened, I was in Canada, and I had to have it towed back into the States.This cost me $250.00. Not good, since it wasn't even fixed. I have been told that it maybe my oxygen sensors? I am at a lost to what to do next. If I was able to afford to take to a Ford dealer, I would. Unfortunetly,I can't. Any ideas, Please help me. Shawnee  

I have the same problem with my Mazda B3000 pickup. I spent over $600 with mechanics trying to figure out my problem, this included the dealership. They still didn't fix the problem but now I get this fuel Composition Sensor fault code and my truck won't start. I can almost get it started for a second but then stalls. It happend twice right after fueling up at a Getty Station. I will never buy Getty gas again, never had problems with mobile gas. Now I don't know what to do since my truck still won't start and the mechanic is at a loss. I will never get another flex fuel vehicle again.  

i have a 2000 ford ranger and have had same trouble with it cutting out and not wanting to run. after getting it towed by aaa to the garage the mechanic ran up a bill of 194.00 just to find that the flex fuel sensor is bad.the cost of this sensor i was told was 700.00,and to fix the rest of the problems with this vehicle(upper and lower ball joints and two tires so it will pass inspection)a total of 1600.00 for a vehicle that has 197,000 miles? wrong ansewer! ford should fix the sensor! as for me im selling it or taking it to the metal recyclers at least i will get my 194.00 $ back from having the mechanic find out what was wrong with it.i wont own another ford!  

i hope you fix your truck but if it helps you i just bought a comp. sensor form a junk yard for $10.00