Question about p0453 on 01 LS V8

DaleGrib

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I have 2 codes right now on my car that are showing up I have p0171 which I know is most likely a vacuum leak and I am getting code p0453. My question is what would cause p0453 I am out of town still and trying to make sure the car is say enough to drive 600 miles to get back home. Does p0453 have anything to do with the fuel pressure sensor? I only ask this because the one guy that broke my old one had to use one from the junk yard. And if so could this also be possibly causing the p0171 code as well?
 
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That's the evap system. You are safe to drive with that fault. It is unlikely to be related to the bank 1 lean condition, unless its because the evap system isn't getting enough vacuum.
 
That's the evap system. You are safe to drive with that fault. It is unlikely to be related to the bank 1 lean condition, unless its because the evap system isn't getting enough vacuum.
Oh ok so nothing to do with the fuel pressure sensor then? Where would I need to start with that code then in troubleshooting it. I will also say I felt sluggish acceleration once the code set on the car. And the gas mileage has went to crap as well.
 
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I'd start by monitoring the fuel tank pressure sensor readings for a little while to try and get a handle on what is going on. Are they changing, or stuck hi all the time? If always one value, then the sensor or the wiring to it is probably bad. If it does vary some, but doesn't go low when it should, then look for leaks or solenoid valve failure (or the wiring to it).
 
I'd start by monitoring the fuel tank pressure sensor readings for a little while to try and get a handle on what is going on. Are they changing, or stuck hi all the time? If always one value, then the sensor or the wiring to it is probably bad. If it does vary some, but doesn't go low when it should, then look for leaks or solenoid valve failure (or the wiring to it).
Ok so if the pressure is not changing I should check the wire leading to the fuel injector pressure sensor on the injector rail? And if the wire is good then I should replace the Fuel injector pressure sensor right?
Here is a video of the fuel pressure
 
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No, this is not the fuel pressure. It's the fuel tank pressure (FTP) sensor.

The fuel tank pressure (FTP) sensor:

  • monitors the pressure levels in the fuel tank.
  • communicates the pressure reading to the PCM during the OBD II leak test.
  • is permanently attached to the fuel vapor control valve tube assembly.
 
No, this is not the fuel pressure. It's the fuel tank pressure (FTP) sensor.

The fuel tank pressure (FTP) sensor:

  • monitors the pressure levels in the fuel tank.
  • communicates the pressure reading to the PCM during the OBD II leak test.
  • is permanently attached to the fuel vapor control valve tube assembly.
How hard is that to change?
 
Not sure. Why not start by seeing what it's doing before condemning it?
 
That's really low.
Does it change at all?
How about key on, engine off, fuel cap off?

upload_2019-1-26_18-17-51.png
 
The wire colors should be:
White/violet
Yellow/violet
Brown/white

Note that there are very likely wires with the same colors in other places doing other things. The wiring diagram says the sensor is "under rear of vehicle."
 
The wire colors should be:
White/violet
Yellow/violet
Brown/white

Note that there are very likely wires with the same colors in other places doing other things. The wiring diagram says the sensor is "under rear of vehicle."
So it should not be crazy hard to get access to it? I assume just use some jack stands and I should be able to see it?
 
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So it should not be crazy hard to get access to it? I assume just use some jack stands and I should be able to see it?
The wire colors should be:
White/violet
Yellow/violet
Brown/white

Note that there are very likely wires with the same colors in other places doing other things. The wiring diagram says the sensor is "under rear of vehicle."
Is FTP incorporated into the electric fuel pump assembly in the tank.I know that on some vehicles it is...just wondering if this is true for the LS also...kinda hard to follow all this...I'm kinda slow sometimes :)
 
"Common mistakes when diagnosing the P0453 code
Technicians often misinterpret the P0453 code to mean problems with the fuel cap, evaporative purge valve or evaporative vent valve"

Would this part have anything to do with the code? It's a common mistake to thinks it's this part they say but stranger things have happened...
If so I have an extra in the garage bought it for $14 on Ebay they also have this one on Ebay for $49 free shipping I know that you're looking into the sensor but thought I'd throw it out there
VAPOR FILTER EVAP CANISTER CAN PURGE VALVE FUEL VAPOR GAS TANK XW4E-96915-AB CAR

Condition:
Used

“CAR ONLY HAD 53K ON IT. ONLY FITS WITH PART# XW4E-96915-AB DOES NOT INCLUDE THE EXTRA WIRE AND PLUG ”

... Read more

Compatibility:
See compatible vehicles



Price:
US $49.94
Buy It Now-
 
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The fuel tank Pressure is staying at 4.2 kPa
"How does a mechanic diagnose the P045 code?
With key on/engine off, use a scan tool to retrieve the code from the engine’s diagnostic connector. Pay close attention to fuel tank pressure readings, using a scan tool.

  • Normal voltages should be around 2.5 volts, and should never exceed 4.5 volts. A reading of around 2.7V with the gas cap off might indicate an intermittent problem.

  • Use a digital volt/ohmmeter to measure voltage at the signal wire while wiggle-testing wiring at the FTP sensor. A fluctuation in voltage during the wiggle-test could point to connector problems such as broken wiring, corrosion or dampness.

  • If the scan tool shows voltages above 4.5V, unplug the sensor (if possible) and recheck the voltage. If voltage is still high with the sensor unplugged, inspect the wiring harness for a short on the signal wire. If high voltage disappears when the sensor is unplugged, check for the sensor’s ground and for proper reference voltage supplying the sensor.

  • If the sensor has a good ground and 5V reference voltage, it’s likely that the sensor itself has failed and needs to be replaced.

  • The pressure sensor can also be tested with a vacuum gauge while connected to the wiring harness, as you observe the data stream’s change on a scan tool.

  • If after replacing the sensor and all test results are within spec, the problem might be with the PCM itself. Remember that failed PCMs are rare and replacing the PCM will require complete reprogramming.
  • What repairs can fix the P0453 code?
 
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Is FTP incorporated into the electric fuel pump assembly in the tank...

No, of course not. If it were in the tank, wiring to the sensor would have to pass into the tank. Note that the fuel pump connector only has wires to power the pump and to read the fuel level sender.
 
No, of course not. If it were in the tank, wiring to the sensor would have to pass into the tank. Note that the fuel pump connector only has wires to power the pump and to read the fuel level sender.
Okay thanks for the info Joe...appreciated
 
Have you looked at all the plugs on Bank #1? Lean means misfire ...maybe why it's feeling sluggish and poor gas mileage?
I Have not checked the plugs considering I literally just replaced them. I really don't see a need to pull the plugs at this point. I mean I suppose it could be plugs but I highly doubt it. P0171 takes quite a while to come back once I have cleared it so I am leaning toward a minor vacuum leak on that. Also as cold as it is I think that is playing a big part of the poor gas mileage I mean it has been 3 degrees and lower lately.
I won't be able to do anything most likely till I get back home from this trip unless I can find someone with a floor jack and some jack stands. Then I can at least check out the connector to the FTP sensor. I have a feeling it's a bad connector cause last night when I cleared the code it came right back on as soon as I cranked the car and I tired many times to clear the code! But today so far the code has not came back but I am sure it will at some point. I will go out and check the Fuel tank pressure again once I get some time today maybe it's working as it should now and I just need to fix the connector. I know the guy at the parts store said it was a better chance of having a bad connction or wire than that sensor typically being bad.
 
I did discover a problem this morning the fuel is somehow leaking around the fuel pump for some reason. Obviously I know have to fix this problem ASAP but could it be related to either of the 2 codes I am seeing?
IMG_20190128_105307035.jpg
 
I am hoping the fuel pump did not get a good seal when it got put back in. I don't see any fuel leaking around the lines. I am thinking it's just leaking when the tank is really full. I am gonna talk to a neighbor where I am at right now they work on cars so hopefully they can work something out for me. Cause I could not even smell it so I would assume the gas has been there for days. And the tank is low on fuel right now which is a very good thing considering.
 
I am hoping the fuel pump did not get a good seal when it got put back in. I don't see any fuel leaking around the lines. I am thinking it's just leaking when the tank is really full. I am gonna talk to a neighbor where I am at right now they work on cars so hopefully they can work something out for me. Cause I could not even smell it so I would assume the gas has been there for days. And the tank is low on fuel right now which is a very good thing considering.
I've had to work on this fuel pump extensively ...first and formost make sure the O ring gasket is properly seated before screwing on the blue ring...is this the original fuel pump assembly module?
 

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