I have done a search, but that does not mean I did it right.

That being said, I have a code P0450 showing up on my scanner, no CEL, code list point at the tank pressure sensor reading implausible (bad sensor?)

So, I have a few questions,
1, Is there a test I can perform on this sensor before I drop $125 for a replacement?
2, If I must replace it, where is it located/ how does one access it (I can assume it's on the tank, but you never know with these cars)

Thanks in advance, Greg

 

Personally, I don't think it's a sensor. Replace the more obvious cause of a P0450. Believe it or not, the gas cap can cause problems with tank pressure and throw this code. It's a cheap part from Porsche. Next, is the bleeder value which is behind the fender liner. IMHO, many people rush to replace sensors, but in reality, they're doing there job to alert a problem. If it's not significant enough, to throw a CEL, then I would just start by replacing the gas cap and keep a close eye on other possibilities. You may also have a more serious fuel pressure issue with the fuel pump. More talented service techs here on Rennlist may have a better way to zero in on the exact problem.

 

I second the gas cap. Just get a new one.

 

I have been trying to find a solution to my P0451 code which also points toward the Fuel Tank Pressure sensor. I have no driveability issues. Do you?

Here is a link to the location of the Fuel Tank Pressure Sensor.

https://rennlist.com/forums/996-foru...with-pics.html

I have been chasing codes for the past year, but not really any driveability issues. I was having the P0455. Replaced the gas cap, fuel tank vent valve & purge valve. No longer getting the P0455, then started getting P0446 last year. This year I'm getting the P0451. I'd be interested in what works for your P0450.

I have seen tests on YouTube for this sensor.

 

If it were me, I'd do a smoke test on the EVAP system.
But to safely smoke test the EVAP system requires nitrogen.
Most technicians, and shops, don't have nitrogen for some reason that I don't understand!
If I can afford a nitrogen tank for my smoke machine, why can't most shops?

 

Check the seal on your gas cap. I bet there's cracks in it, like mine.

 

I replaced the cap last year. It seems to be holding vacuum now. I can hear the sucking noise when I remove the cap now. When I first got the car just over a year ago I didn't always have that.

 

Same part number as Porsche but half price:

RKX Gas cap replacement seal Fuel

 

I replaced my fuel tank pressure sensor, the one located under the battery tray. It was a bit hard to pull off due to the amount of vacuum holding it in place. It made a sucking noise for a few seconds after pulling it off.

There was a pending P0451 code prior to removing the sensor. I checked the codes immediately after replacing the sensor with the car at idle. The code was no longer pending. Then I went for a 10 minute ride and warmed the car up. The code never came back. So it appears this sensor was faulty.

I appreciate and have benefited from the contributions of many others on this forum, so it was the least I could do to come back and let others know what fixed my P0451. For my 03 C4S it was Bosch PN 0261230015. The part I removed was stamped Bosch with the same part number on it.

Thank you all for the suggestions.

 

Did we miss an update?

 

Nope did not miss an update, while I did replace the gas cap, I have not driven the car for almost two weeks, been too busy with work and planting/ redesigning the garden and back yard.
Once this is all settled, I will have my weekends back, and get some miles on it.
I will update as soon as I have something.

Greg

 

Thanks!
I just ordered a couple.