Help! Am I experiencing vapor lock?

[uabchris]

Well, its been a month now and I am still trying to pinpoint the source of my 00 Boxster not starting (only after adding fuel). I fuel up then have to depress the gas to the floor and then starts after about 5-10 seconds, runs like crap until the computer resets itself then I am good to go until the next trip to the gas station. I get an occasional P0446 (charcoal canister) code but all lines are clear. To troubleshoot the shutoff/purge valves I decided to fuel the car while running. As soon as I inserted the gas nozzle (which depressed the tab at the end of the fuel neck) the car started to run rough. As I put in a few gallons the car wanted to stall so I stopped and removed the nozzle...the idle returned to normal. When depressed, the tab at the fuel neck seems to operate 2 valves: The purge valve behind the RH headlight inside the fender, which I relpaced...no fix. There is also another valve next to the purge valve...could this be the problem? The other valve seems to be out of sight but close to the base of the neck on the fuel tank.

Sorry I,m a pain but my Boxster's getting old. Anyone have any ideas? :help:

* The other valve next to the purge valve?

* The valve at the base of the neck?

* Any of the other air valves on the neck near the charcoal canister?

* Or ???

Thanks in advance!!!

Chris Hewett

00 Boxster

2.7 5 speed

162,000 miles

[juniinc]

U mean the shut off valve ? I would check the triger wire+ground to B+, if the purge valve is operting fine.

possibility is U got a faulty tank pressure sensor or shutoff valve,,, have a feeling most likely it's the sensor?

Stefan's pic

What happens for this system to work is the EVAP canister's shut off valve is closed and the purge valve is opened. This in turn allows vacuum to build up in the system and is measured by the pressure sensor. When a specified vacuum is reached the purge valve is closed. Now the pressure sensor measures the given vacuum over a set time. Should there be a leak the vacuum will drop accordingly. When the shut off valve is faulty no vacuum is built up at all. The purge valve when faulty allows the vacuum to be built up , however it doesn't close so the sensor never has that constant base reading to start by(PCA)

Well, its been a month now and I am still trying to pinpoint the source of my 00 Boxster not starting (only after adding fuel). I fuel up then have to depress the gas to the floor and then starts after about 5-10 seconds, runs like crap until the computer resets itself then I am good to go until the next trip to the gas station. I get an occasional P0446 (charcoal canister) code but all lines are clear. To troubleshoot the shutoff/purge valves I decided to fuel the car while running. As soon as I inserted the gas nozzle (which depressed the tab at the end of the fuel neck) the car started to run rough. As I put in a few gallons the car wanted to stall so I stopped and removed the nozzle...the idle returned to normal. When depressed, the tab at the fuel neck seems to operate 2 valves: The purge valve behind the RH headlight inside the fender, which I relpaced...no fix. There is also another valve next to the purge valve...could this be the problem? The other valve seems to be out of sight but close to the base of the neck on the fuel tank.

Sorry I,m a pain but my Boxster's getting old. Anyone have any ideas? :help:

* The other valve next to the purge valve?

* The valve at the base of the neck?

* Any of the other air valves on the neck near the charcoal canister?

* Or ???

Thanks in advance!!!

Chris Hewett

00 Boxster

2.7 5 speed

162,000 miles

Edited August 21, 2008 by juniinc

[silver arrow]

Wow, 162,000 miles. That's the most I've seen for a Boxster. Are you on the original engine?

[uabchris]

Thanks for the help, your advice makes sense as I can hear both purge/shutoff valves operate upon depressing the tab on the neck. I will try the wire and the sensor and see what happens. :thankyou:

Chris

U mean the shut off valve ? I would check the triger wire+ground to B+, if the purge valve is operting fine.

possibility is U got a faulty tank pressure sensor or shutoff valve,,, have a feeling most likely it's the sensor?

Stefan's pic

What happens for this system to work is the EVAP canister's shut off valve is closed and the purge valve is opened. This in turn allows vacuum to build up in the system and is measured by the pressure sensor. When a specified vacuum is reached the purge valve is closed. Now the pressure sensor measures the given vacuum over a set time. Should there be a leak the vacuum will drop accordingly. When the shut off valve is faulty no vacuum is built up at all. The purge valve when faulty allows the vacuum to be built up , however it doesn't close so the sensor never has that constant base reading to start by(PCA)

Well, its been a month now and I am still trying to pinpoint the source of my 00 Boxster not starting (only after adding fuel). I fuel up then have to depress the gas to the floor and then starts after about 5-10 seconds, runs like crap until the computer resets itself then I am good to go until the next trip to the gas station. I get an occasional P0446 (charcoal canister) code but all lines are clear. To troubleshoot the shutoff/purge valves I decided to fuel the car while running. As soon as I inserted the gas nozzle (which depressed the tab at the end of the fuel neck) the car started to run rough. As I put in a few gallons the car wanted to stall so I stopped and removed the nozzle...the idle returned to normal. When depressed, the tab at the fuel neck seems to operate 2 valves: The purge valve behind the RH headlight inside the fender, which I relpaced...no fix. There is also another valve next to the purge valve...could this be the problem? The other valve seems to be out of sight but close to the base of the neck on the fuel tank.

Sorry I,m a pain but my Boxster's getting old. Anyone have any ideas? :help:

* The other valve next to the purge valve?

* The valve at the base of the neck?

* Any of the other air valves on the neck near the charcoal canister?

* Or ???

Thanks in advance!!!

Chris Hewett

00 Boxster

2.7 5 speed

162,000 miles

[uabchris]

Nope. 1st one died at 95K. I have pretty much replaced everything on the car but the rack and the tranny. :wrench:

Wow, 162,000 miles. That's the most I've seen for a Boxster. Are you on the original engine?

[silver arrow]

Nope. 1st one died at 95K. I have pretty much replaced everything on the car but the rack and the tranny. :wrench:

Wow, 162,000 miles. That's the most I've seen for a Boxster. Are you on the original engine?

****, got my hopes up. Mine has 62,000 miles and I'll just hoping to get to 100,000 before I do a swap. I just don't have the clams to do it now.

[1schoir]

Wow, 162,000 miles. That's the most I've seen for a Boxster. Are you on the original engine?

Marc W has 197K on the original engine in his 2000? Boxster and Pedro has over 165K on the original engine on his 1997. Both are over on PPBB.

So, I guess there's hope for some of us still.

Regards, Maurice.