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In my particular case the p0181 was affecting my cars performance. Once the light came on for it I was running just a hair lean in wot. I checked my fuel pressure, fuel pump, injectors, as well for vaccum leaks. Fixed some issues here and there but didnt solve my lean boost problem. Ultimately did turn out to be the fuel temp sensor for me. Dropped the tank and replaced and am back to target afrs. I do have an iat sensor for my speed density setup so made me doubt that the fuel temp sensor was it initially. Perhaps the way my tuner set it up also utitlized fuel temp.
Funny that you mention this, because I myself noticed when doing pulls on E85, I was going very lean ( I didn't get the check engine light yet though ). However I thought this was maybe due to different ethanol content used at the pumps. When I switched back to 93, AFR's are usually in the 10's at WOT. It wasn't until I switched to 93 after a tank or two, I get the check engine light after about 150ish miles.
Is it recommended that this sensor is replaced? I looked at dropping the tank, and it's quite the pain. If I could have my tuner bypass it, I'd much rather go that route assuming I can drive the car safely again.
Yes I'm sure your tuner can bypass it as most people seem to do. If yours is bad just install a gm iat sensor in uicp and have him disable fuel temp in rom. I would've went that route myself but my tuner is a pain to get a hold of and I didnt wanna pay for a new tune from someone else with my same engine setup lol.
My experience dropping the tank was that it wasnt overly difficult but very time consuming. Doing all the work on the ground and jumping from side to side to complete the work was tiring to say the least.
I just had this code pop up last night as well & this is what I found:
DESCRIPTIONS OF MONITOR METHODS
If the fuel tank temperature is found to be higher than the engine coolant temperature by a prescribed value, through a comparison
between the engine coolant temperature and the fuel tank temperature when the engine is started cold, a malfunction is determined
to have occurred.
MONITOR EXECUTION
Continuous
Check Conditions
The engine coolant temperature - intake air temperature is 5°C (9°F) or less when the engine is started.
The engine coolant temperature is between - 10°C (14°F) and 36°C (96.8°F) when the engine is started.
Engine coolant temperature is higher than 60°C (140°F).
Maximum vehicle speed is higher than 30 km/h (19 mph) after the starting sequence has been completed.
Judgement Criterion
The fuel tank temperature - engine coolant temperature is 15° C (27° F) or more when the engine is started.
I've also attached the complete article just in case you really want to dive in head first..
ive never done it.. .but looks to me you would either have to drop the tank or cut an access hole to get to the sensor.
Bringing this back from the dead. I'm experiencing this code (P0181) too. I looked into dropping the tank and saw Boosted Film's video. No way to I want to tackle it that route. So my questions are: Has anyone went the route of cutting a hole from up to access the sensor? If so, approximately where from the picture did you cut? From the diagram, I'm guessing smack dab in the middle, but toward the rear a bit.
Bringing this back from the dead. I'm experiencing this code (P0181) too. I looked into dropping the tank and saw Boosted Film's video. No way to I want to tackle it that route. So my questions are: Has anyone went the route of cutting a hole from up to access the sensor? If so, approximately where from the picture did you cut? From the diagram, I'm guessing smack dab in the middle, but toward the rear a bit.
I just replaced this sensor a couple of months ago and made a thread showing the details. Im not too sure how to add a link, but if I figure it out ill edit and post the link. Tank DOES NOT need to be fully dropped tho. And I did not cut an access hole either.
I copied and pasted the page but it does not appear to let you click on it to take you to the thread.
Yes, I read your thread--very informative, good job. I also saw the Boosted Films video. Taking everything apart below and doing a slight drop is not my top option. Messing with fuel lines, e-brake, full tank of fuel, just sounds like more ways for me to yell four letter words. I'd rather cut an access hole from up top. Estimating the location and being careful with my depth are my main concerns.
Yes, I read your thread--very informative, good job. I also saw the Boosted Films video. Taking everything apart below and doing a slight drop is not my top option. Messing with fuel lines, e-brake, full tank of fuel, just sounds like more ways for me to yell four letter words. I'd rather cut an access hole from up top. Estimating the location and being careful with my depth are my main concerns.
Ahh, ok i see what you are saying. I also thought about an access hole but thought I would end up with my own butcher job haha. If you do end up cutting an access hole, please post. I would figure it would be much much quicker.
So I decided to tackle the temp sensor from up top, since disassembling everything underneath would be very time consuming and have a number of more things giving headaches. I made a fairly good approximation for where to cut. I used both a rotary tool and angle grinder with cutoff wheel. Please use caution with sparks and take your time. I would cut a bit and check frequently for clearance.
I can reach the harness and all nuts but it’s somewhat tight. If I were to do it all over again, I’d shift that rectangle about an inch toward the front of the car. You can patch it up any way you want.
I think JDM version did not have a fuel temp sensor.
Took about an hour, carefully cutting. Melted sound deadening gummed up cutting discs that added time.
Last edited by son of krypton; Jan 18, 2022 at 09:31 PM.
so i decided to tackle the temp sensor from up top, since disassembling everything underneath would be very time consuming and have a number of more things giving headaches. I made a fairly good approximation for where to cut. I used both a rotary tool and angle grinder with cutoff wheel. Please use caution with sparks and take your time. I would cut a bit and check frequently for clearance.
I can reach the harness and all nuts but it’s somewhat tight. If i were to do it all over again, i’d shift that rectangle about an inch toward the front of the car. You can patch it up any way you want.
Feb 18, 2020, 01:36 PM
