EVAP Canister Valve

[bar10dah]

That valve at the top of the EVAP canister, where the arrow is pointing to, purge valve 996-605-201-01...

...what voltage should be there? Thought mine was bad, so ordered a new one. When I had it apart today, hooked up a voltmeter and got 6.6 V with the ignition on but engine not running. Thought this was the "fuel evaporative valve" in Durametric, so activated it and didn't see any changes in voltage at the connector. Turned the car off, and still got 6.6 V. Started the car and got 7.4 V. Let the car idle for about three minutes, but still got 7.4 V.

The part is labeled 12 V. So, hooked the old part directly up to the battery and the plunger snapped shut (or open, not sure exactly how it works) so the part must be operating correctly. However, should I have a constant voltage at the part, no matter if the ignition is on or off?

[logray]

I breifly scanned the wiring diagram for a 99 and couldn't find conclusive info.

The only advice I might have at this point is to test the voltage at the evap valve at the engine near the intake manifold, does it read 12v?

I can't see why the valve near the tank would require different voltage.

Also, 7v does not sound right under any situatoin on this car. You should have 12v or 5v. But not 7.4.

Sorry to say, but if it is supposed to provide and is not providing 12v and the problem is not with wiring, your DME would probably be suspect at this point.

PIn 61 on ME 5.2.2 is for the tank vent valve.

I would do more testing, research and perhaps get some more input before swapping your DME.

[bar10dah]

Thanks Logray. With ignition on, I checked the valve under the driver's side intake manifold and it read 6.6 V engine off. Then tested it with "fuel evaporative valve" activated in Durametric and voltage was flip/flopping between 6.6 and 12 V. So, appears the wiring at that point was getting the correct voltage. I didn't hear any mechanical clicking with that valve. Swapped with a new valve and now I hear clicking.

Still not sure about the valve on the charcoal canister, but at least I tracked down one bad valve. I did replace the valve on the charcoal canister as well. Maybe a certain drive condition must be met before 12 V is applied to the valve on the charcoal canister?

[bar10dah]

Still curious as to why both connectors were showing 6.6 V? Is that just the offset baseline voltage for that circuit? I can't imagine why a baseline other than 0 V would be helpful.

[logray]

IIRC the purge valves operate when engine is hot.

[Pierre's Porsche]

What's the "trick" to removing the electrical connector on the evap. purge valve located under the intake?

[EricP]

I have a 2001 Base and purchased a new vapor canister valve. I removed the front tire and part of the cowling(?) but was unable to locate the valve to replace it. Anyone have any suggestions how I mat find it?

Thanks,

-Eric

[Loren]

I have a 2001 Base and purchased a new vapor canister valve. I removed the front tire and part of the cowling(?) but was unable to locate the valve to replace it. Anyone have any suggestions how I mat find it?

Thanks,

-Eric

Did you look at the image in the first post of this thread?

[EricP]

Yes I did, and zoomed in. Maybe different model years?

[Loren]

Yes I did, and zoomed in. Maybe different model years?

That was a MY99 car I was working on.

Have a look at removing the whole canister as that is easy and then you should see things more clearly.

http://www.renntech.org/forums/tutorials/article/45-replacing-the-gasfuel-door-actuator/

[EricP]

Did they move this valve to the engine area in '01? The parts diagram shows the valve at the other end of the line, or am I missing something?

It's part #9 in this link http://www.autoatlanta.com/porsche-parts/986-97-04/201-20.php?pn=99660521301#a but where is that top assembly located?

[Loren]

Did they move this valve to the engine area in '01? The parts diagram shows the valve at the other end of the line, or am I missing something?

It's part #9 in this link http://www.autoatlanta.com/porsche-parts/986-97-04/201-20.php?pn=99660521301#a but where is that top assembly located?

Perhaps you need to be more specific on which valve you are talking about - as the one in this thread is the one on the canister.

What was your fault code(s)?

[JFP in PA]

Did they move this valve to the engine area in '01? The parts diagram shows the valve at the other end of the line, or am I missing something?

It's part #9 in this link http://www.autoatlanta.com/porsche-parts/986-97-04/201-20.php?pn=99660521301#a but where is that top assembly located?

I think you are referring to the tank venting valve (item #20 in the diagram) is under the driver's side intake runners, near the throttle body:

[EricP]

Did they move this valve to the engine area in '01? The parts diagram shows the valve at the other end of the line, or am I missing something?

It's part #9 in this link http://www.autoatlanta.com/porsche-parts/986-97-04/201-20.php?pn=99660521301#a but where is that top assembly located?

Perhaps you need to be more specific on which valve you are talking about - as the one in this thread is the one on the canister.

What was your fault code(s)?

I ordered part# 99660521301 based on reading a couple threads and getting the P0446 code on my car. I have replaced both sensors in front of the pre cats, still getting the P0446 and also P1128 & P1130. I saw a couple threads here refernceing this valve as well as the one under the intake manifold. Also when I fill up with gas the car is very hard to start, I have to crank it several times and also use the gas pedal, making me think the evap tank valve may be the better choice to replace. I welcome any suggestions.

-Eric

[JFP in PA]

Did they move this valve to the engine area in '01? The parts diagram shows the valve at the other end of the line, or am I missing something?

It's part #9 in this link http://www.autoatlanta.com/porsche-parts/986-97-04/201-20.php?pn=99660521301#a but where is that top assembly located?

Perhaps you need to be more specific on which valve you are talking about - as the one in this thread is the one on the canister.

What was your fault code(s)?

I ordered part# 99660521301 based on reading a couple threads and getting the P0446 code on my car. I have replaced both sensors in front of the pre cats, still getting the P0446 and also P1128 & P1130. I saw a couple threads here refernceing this valve as well as the one under the intake manifold. Also when I fill up with gas the car is very hard to start, I have to crank it several times and also use the gas pedal, making me think the evap tank valve may be the better choice to replace. I welcome any suggestions.

-Eric

Fill up problems are usually related to the flapper in the fill neck which is totally unrelated to your issues, do a search as it is often as simple as a blown fuse.

P0446 is for high flow resistance in the EVAP canister, usually associated with blocked purge air line. Replacing the O2 sensors was a common mistake for the P1128 and 1130 codes, which is an indication of an overly lean condition caused by intake air leaks or low fuel delivery problems causing the engine to run overly lean, there was nothing wrong the sensors.

[EricP]

Fill up problems are usually related to the flapper in the fill neck which is totally unrelated to your issues, do a search as it is often as simple as a blown fuse.

P0446 is for high flow resistance in the EVAP canister, usually associated with blocked purge air line. Replacing the O2 sensors was a common mistake for the P1128 and 1130 codes, which is an indication of an overly lean condition caused by intake air leaks or low fuel delivery problems causing the engine to run overly lean, there was nothing wrong the sensors.

OK, that makes a lot of sense, thank you. I agree (now) that there was nothoing wrong with the sensors :)

Based on a thread I read I would need to either replace the valve I purchased, or another valve ( http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=996-110-129-06-M100&catalog_description=&Regeneration%2520Valve%2520from%2520Throttle%2520Body%2520for%2520Fuel%2520Vapor%2520System%252C%2520Boxster%252FBoxster%2520S%2520%2528%2531%2539%2539%2537%252D%2530%2534%2529%252C%2520Each%2520 ) which I think is the one that runs under the intake previously mentioned.

-Eric

[JFP in PA]

Fill up problems are usually related to the flapper in the fill neck which is totally unrelated to your issues, do a search as it is often as simple as a blown fuse.

P0446 is for high flow resistance in the EVAP canister, usually associated with blocked purge air line. Replacing the O2 sensors was a common mistake for the P1128 and 1130 codes, which is an indication of an overly lean condition caused by intake air leaks or low fuel delivery problems causing the engine to run overly lean, there was nothing wrong the sensors.

OK, that makes a lot of sense, thank you. I agree (now) that there was nothoing wrong with the sensors :)

Based on a thread I read I would need to either replace the valve I purchased, or another valve ( http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=996-110-129-06-M100&catalog_description=&Regeneration%2520Valve%2520from%2520Throttle%2520Body%2520for%2520Fuel%2520Vapor%2520System%252C%2520Boxster%252FBoxster%2520S%2520%2528%2531%2539%2539%2537%252D%2530%2534%2529%252C%2520Each%2520 ) which I think is the one that runs under the intake previously mentioned.

-Eric

Picture is a bit poor, but that looks like the item. You should also blow air into the purge air line (item#3 in diagram):

[EricP]

Fill up problems are usually related to the flapper in the fill neck which is totally unrelated to your issues, do a search as it is often as simple as a blown fuse.

P0446 is for high flow resistance in the EVAP canister, usually associated with blocked purge air line. Replacing the O2 sensors was a common mistake for the P1128 and 1130 codes, which is an indication of an overly lean condition caused by intake air leaks or low fuel delivery problems causing the engine to run overly lean, there was nothing wrong the sensors.

OK, that makes a lot of sense, thank you. I agree (now) that there was nothoing wrong with the sensors :)

Based on a thread I read I would need to either replace the valve I purchased, or another valve ( http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=996-110-129-06-M100&catalog_description=&Regeneration%2520Valve%2520from%2520Throttle%2520Body%2520for%2520Fuel%2520Vapor%2520System%252C%2520Boxster%252FBoxster%2520S%2520%2528%2531%2539%2539%2537%252D%2530%2534%2529%252C%2520Each%2520 ) which I think is the one that runs under the intake previously mentioned.

-Eric

Picture is a bit poor, but that looks like the item. You should also blow air into the purge air line (item#3 in diagram):

Thanks for the diagram. It's strange, I found this thread (http://www.renntech.org/forums/topic/33970-strange-whistling-sound/?hl=%2Bstrange+%2Bwhistling+%2Bsound) last night and it references the valve I purchased being located basically behind the passenger side headlight. I think his was a MY '00, did they change things that much year over year?

Thanks for all your help, it's been helpful.

-Eric

[JFP in PA]

Fill up problems are usually related to the flapper in the fill neck which is totally unrelated to your issues, do a search as it is often as simple as a blown fuse.

P0446 is for high flow resistance in the EVAP canister, usually associated with blocked purge air line. Replacing the O2 sensors was a common mistake for the P1128 and 1130 codes, which is an indication of an overly lean condition caused by intake air leaks or low fuel delivery problems causing the engine to run overly lean, there was nothing wrong the sensors.

OK, that makes a lot of sense, thank you. I agree (now) that there was nothoing wrong with the sensors :)

Based on a thread I read I would need to either replace the valve I purchased, or another valve ( http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=996-110-129-06-M100&catalog_description=&Regeneration%2520Valve%2520from%2520Throttle%2520Body%2520for%2520Fuel%2520Vapor%2520System%252C%2520Boxster%252FBoxster%2520S%2520%2528%2531%2539%2539%2537%252D%2530%2534%2529%252C%2520Each%2520 ) which I think is the one that runs under the intake previously mentioned.

-Eric

Picture is a bit poor, but that looks like the item. You should also blow air into the purge air line (item#3 in diagram):

Thanks for the diagram. It's strange, I found this thread (http://www.renntech.org/forums/topic/33970-strange-whistling-sound/?hl=%2Bstrange+%2Bwhistling+%2Bsound) last night and it references the valve I purchased being located basically behind the passenger side headlight. I think his was a MY '00, did they change things that much year over year?

Thanks for all your help, it's been helpful.

-Eric

The drawing I gave you is from the 2001 OBD II diagnostics manual for the 986 Boxster, and is current and correct to my knowledge. But I need to point out that Loren is correct, there are valves at the EVAP canister, which is in the passenger's wheel well, as well us under the intake manifold; you need to be sure about which valve you are asking about, there is more than one..............and the one pictured in the thread you brought up is at the canister while the purge valve is under the intake runners.........

[EricP]

The drawing I gave you is from the 2001 OBD II diagnostics manual for the 986 Boxster, and is current and correct to my knowledge. But I need to point out that Loren is correct, there are valves at the EVAP canister, which is in the passenger's wheel well, as well us under the intake manifold; you need to be sure about which valve you are asking about, there is more than one..............and the one pictured in the thread you brought up is at the canister while the purge valve is under the intake runners.........

OK, that's what I have sort of figured out during all this research. I will try this valve this weekend and hopefully not move on from there :)

-Eric

[EricP]

I apparently ordered the wrong valve (which is the other valve in the assembly) and so I will have to wait until the correct valve arrives to complete this task. I did check fuse E6 and it is fine. Any other thoughts as to why it would be difficult to start after filling up (and this only ever happens after filling up, otherwise starting is not an issue).

When the correct valve arrive, I also plan to remove and check the valve on the canister as that is the one I errantly ordered.

There are 2 valves located in an assembly behind the passenger headlight, basically directly above the tire. I was able to get in there and remove both valves from the headlight opening.

Thanks,

-Eric

[EricP]

I replaced both valves that are located above the front passenger tire, behind the headlight. Still getting the same codes. I wasn't able to get the valve changed in the evap canister, I may try again, I had trouble getting the canister out and was running out of time.

I am getting a sound which I tracked to the vent that is near the gas cap, which comes from where I replaced the valves. Sounds like a fan or motor type noise, but I think it's a sucking sound. I can stop the noise by putting my finger over the vent tube. I have also ordered the other valve (#1 from the diagram). Could that one be related? If bad maybe drawing in too much air?

-Eric

[txhokie4life]

Replace the valve that is under the drivers side intake.

Seen this on an 00 Base and an early 2000ish S (not sure what year it was)

m

[JFP in PA]

Replace the valve that is under the drivers side intake.

Seen this on an 00 Base and an early 2000ish S (not sure what year it was)

m

It is also common for the line that lead to the valve under the intake to become plugged, so it would be advisable to blow it out with some low pressure air after disconnecting it at both ends.

[EricP]

I have the valve, does the intake need to be removed to get to the valve?