today my 01 disco 2 CEL came on with p0181 (fuel temp sensor issue) I didnt think our v8 discos had one. I cant seem to find any detail about it in the service manual. is my code reader playing games with me?

a little back ground on this on going problem. a few weeks ago it developed a bit of a rough idle cold or hot. at that time it was storing a code about the maf and a multiple mis and mis at cyl 4. i at that time replaced the maf with a genuine maf and did 02 sensors on that bank for good measure. it then ran smoother cold and even seemed to make more power that before but once up to temperature and sitting in traffic it would idle bad again. not as bad as before, it felt like more of a hotrod with hot cams or something. the other codes have not shown but today sitting in traffic p0181 came up. the only other thing i can see is the fuel trims for that bank are still high. the long trim seems to sit somewhere around +13 and the second o2 is reading a richer fuel mixture than that driver side.

 

"This code sets when the ECM doesn't like the fuel temperature sensor data as compared with the coolant temp. Could be caused by a faulty sensor, bad connection/broken wire, or faulty ECM. The Fuel Temp Sensor is on the fuel rail, and has a 2-pin connector. You can unplug and test it with an ohmmeter, at 100 degrees it should have about 1000 ohms across the terminals, at 70 degrees it should have about 2700 ohms. If it checks out at the sensor, you can plug it back in, and unplug your . Check the resistance between pin 35 and pin 36, if its not very close to your measurement at the sensor, you've got a wiring issue."


this is from a thread on another site from several years ago ^^^. what are your coolant temps on your scanner? if your coolant temp isnt being reported correctly it will play all kinds of tricks on the system. your long term trims are indicating a lean condition, the computer is adding fuel because it thinks its getting to much air. Is your rich fuel trim on the same side that as the new O2 sensor?

 

I will have to take a look at the fuel temp sensor. And yes the rich fuel trim is on the side of the new o2 sensor. At the same time I will swap the sensors left to right to see if the trim follows it. Coolant temps seem to hover around 189. I have the 180 thermostat installed. Is the sensor easy to get to or will I have to pull the upper intake manifold. Thanks for the help btw

 

There def is no sensor on a D2 fuel rail so don't drive yourself crazy looking for that LOL
You still have a faulty sensor or maybe even a vacuum leak with that LT trim @13%+
I don't have any experience related to this but I know it could be 1 of several different things causing the fueling issue. Make sure there are no vacuum leaks @ Injector Orings or otherwise.

 

Unless a TD5, doubt so but...?
......

 

I wish

 

have you done any top-end work on this truck? You can play around with the sensors but I would search for vac' leaks @ the lower intake, removing the banana mani' & fuel rail if it's positive for vacuum. Spray test all of the injectors to confirm pattern & proper function then reassemble with new Orings & add 1 new upper mani' gasket to the orig already there giving a better seal b/w the upper & lower manifolds.

Please let me know what you find as I have a couple of tips before you begin disassembly. Test for vac with vapor/smoke first, then a combustible chemical if the vapor doesn't show anything. I assume that you know how this works, if not there is info available via a search.

 

You are using top tier premium/supreme grade fuel right?

 

last year i did a top end overhaul. head gasket and all the seals associated with taking stuff apart as well as new heads. BUT! i drove home today for the first time with the window down (it was the first warm day here in upstate ny in a while) and i heard the magical sound of an air leak. if i rev it sounds like a turbo waste gate. i popped the hood and the sound is coming from the same side of the engine i am getting the high fuel trim on. so in my free time i will have to hunt the leak down. unfortunately with 2 jobs i dont have the most time. at any rate thanks everyone for the suggestions and support. i will keep the forum posted on my soon to be success!

 

oh and it seemed to run better today then the colder days. i can only assume an air leak with cold dense air is harder to compensate for than hot air. most days here are under 20 and today was mid 60. and yes always premium fuel