Wayne Smith

Just took my 2010 997.2 C4S PDK with 157K miles in for a California emissions test and came away failed due to a Liquid Fuel Leak Check.

Got home and connected my Foxwell to read the codes and got an ID 8005 in the PAS Control System ... Upper limit value exceeded on Terminal S.

No CELs or any other indications. No noticeable symptoms or problems with vehicle operation.

Have a trip coming up and would like to eradicate this first. Any thoughts on where to attack this?

Thanks in advance ... Wayne

groovzilla

Sorry to hear this Wayne - What a PITA emission tests are. Glad they did away with them up here in Wa State.
Hope it's a simple fix.

Bruce In Philly

2009 C2S 197K miles

Bummer... you probably already saw this: https://www.renntech.org/topic/48721...c-diagnostics/

Peace
Bruce in Philly (now Atlanta)

CAVU

PAS comes back in AllData as "Passive Access System". Might be unrelated but might this be it: https://www.smog-tech-training.com/S...uel-leaks.html

MrMoose

If you've got a vapor leak in the tank it'll typically throw a CEL and codes. For a "liquid fuel leak check" that may just be part of the tech's visual inspection, and you probably have to talk to the guy to understand exactly what he saw. Do you know if they actually plugged the car in to the computer, or did they fail it at the visual test stage?

It's entirely possible the tech saw some leak, assumed it was fuel, and flagged it. Not all smog check guys have a clue.

jchapura

https://www.vistasmogcheck.com/smog-...quid-fuel-leak

Wayne Smith

The car did get plugged into the computer. It passed everything, including visuals. The tech figured that this was a last code waiting to be cleared after a battery power loss or code reset.

But the car has been driven some hundreds of miles since I showed my grandson how the Foxwell communicated with the car's computers. So errors have been reset as a part of my training Cree about cars. I figure this is a true error that, while the internet states is a visual check, does come up in the codes ... and the tech said this was an error based on the OBD II reading ...

ID 8005 in the PAS Control System ... Upper limit value exceeded on Terminal S

My first thought was charcoal canister, but that shows as a different code.

So I've been trying to figure out how this situation could be diagnosed by the computers in the car ...

1. Sniff detectors ... I'm not seeing that!!!
2. Reduced pressure on the fuel rail after the motor was switched off.

2 makes sense as a possibility, and the sensors exist for fuel pressure. This could indicate an injector leaking or an HPFP starting to fail. Or a loose fitting. Any of these could reduce pressure indicating a leak.

But I'm guessing.

Meanwhile, if this is a real problem, then it's good that the smog check forewarned me.

Bruce In Philly

"Upper limit value exceeded" ... hmm, failed sensor?

Peace
Bruce in Philly (now Atlanta)

Wayne Smith

A good question ...

Wayne Smith

One more data point ... I opted to erase the codes tonight, and the PAS section passed. That's a passive pass with the motor off. I'll head out on a quick drive tomorrow to see what happens and report back.

groovzilla

So wayne was the fail NOT because of a visual fuel leak by Emissions Tech?
Tech is going by code that came up?

Wayne Smith

Yes, the failure was due to a code from the OBD II. There is no visual leak. And yes, internet posts say this failure is a visual check. But per the smog test report as well as my Foxwell reader, there is a code on our cars that leads to this same conclusion. And the tech specifically stated it was a code rather than a visual.

The failure could be erased and it stayed clear without starting the motor. My frunk light error is a front computer sensor problem and will not clear. So I'm assuming if this was a sensor problem it also would not clear. So I don't feel this is a sensor problem, but what do I really know?!?!?!

FWIW, this problem popped up AFTER I used an injector cleaner with PEA. Why did I use this? I'll quote Bruce ... Dunno!!!!

I'm thinking that perhaps this broke a chunk off from somewhere and created a leakage problem in an injector where there was not one.

So on the way to help a friend install cabinets yesterday I picked up some more injector cleaner to put in the tank when I fill up later today.

I'll take the Foxwell to my friend's today and read the codes immediately after stopping the car and then later after a possible leak reduces fuel rail pressure. Hopefully this will narrow things down.

More as I know more ...

jchapura

Do you have access to the technician's/maintenance guide that might show the control schematic that would throw the CEL code you have. Then you'd know which sensors are involved and be able to assess how easy they are to replace.

The theory about the recent PEA is also a good one. Keep PEAing on it in the hopes to clearing the chunk. After PEAing, some suggest an oil change.

MrMoose

Something seems strange here. An old stored code should not cause a smog test failure. When they plug in they're checking for active codes and the OBD monitor status.

If there are no active codes and the monitors are all in "ready" state then there shouldn't have been an issue. Does the reader say any monitors are pending?

Wayne Smith

The only stored code listed as pending was ...

ID 8005 in the PAS Control System ... Upper limit value exceeded on Terminal S

This did not throw a CEL so I was a bit surprised when I failed.

After clearing codes last night and a couple of short drives today the PAS remains faultless. But I need to drive further before I csn retest. I've got a long drive Tuesday to do some construction stuff for a friend. Same on Wednesday. If the code fails to come back I'll chalk it up to a dirty injector and take it in Thursday for a retest.

More as I know more ...

Thanks for all of the support in the meantime.