E46 Fanatics Forum banner

How to do I replace the EVAP Purge Valve (a.k.a. Fuel Tank Breather Valve)?

125K views 46 replies 21 participants last post by  teKcirc 
#1 ·
I downloaded the OBDII code and discovered that I need to replace my Evaporative Emissions (EVAP) Purge Valve [some people know it to be the Fuel Tank Breather Valve]. I've located the EVAP purge valve mounted beneath the intake manifold. It looks like I either need to remove the intake manifold or remove the air filter housing to even have a chance to reach it. Unfortunately, there isn't much detailed DIY information on this subject for the 2002 325i (E46).

What's the easiest way to gain access to the EVAP purge valve/fuel tank breather valve and replace it?
 
#3 ·
It's not the tank breather line. The OBDII fault code was PO444 which indicates an open circuit on EVAP purge valve (fuel tank breather valve). I spoke with one of the service techs at the local dealer. He says it's most likely the solenoid on the EVAP purge valve went bad.

If I'm looking to replace the EVAP purge purge valve, what's the easiest way to get to the purge valve? Is it by removing the air filter housing?
 
#4 ·
Slide under the car, and look up, at the rear of the passenger side below the trunk and right below the fuel tank filler-neck where you add gasoline. There is a black plastic box, a little smaller than a shoe box. Unlatch the bottom-cover by sliding the little button-ears under the latches. Look for the solenoid, which will look like an iron core with a lot of copper wires wound around it. Unclip the solenoid and the wires. Pop off the front end of the solenoid, clean the o-ring with alcohol, and lightly regrease the o-ring with di-lectric grease or vasoline jelly. Re-install everything and clear the codes. This worked for me. My trouble code was something like "small leak at the evap purge valve." That was 50,000 miles ago and it has not returned.
 
#30 ·
Hi, I replaced the purge valve underneath the manifold as well as followed the instruction above about cleaning the o-ring but it's still throwing the code. Does anyone else have any idea why I'm still getting the error code? Any other parts or anything I should be check/testing? Thanks in advance...
 
#5 ·
Hmm...I thought the purge valve was located underneath the intake manifold on a 2002 325i (E46) and the solenoid was integral to the purge valve body (one part). That's what was mentioned to me by the dealer service tech [and what I observed first hand opening the hood]. The BMW part number is 13901433603. Can anyone else confirm this?
 
#6 ·
#7 ·
Thanks Tom for your input and the links. It's much appreciated. The only thing I don't see in the other person's description is how he actually got access to work on the purge valve. It just describes how they traced out the breather line to find the purge valve.

After contemplating about it some more and looking at it under the hood again, I think I'll try to remove the air filter housing to try to reach the purge valve under the intake manifold. It just seems like it may turn out to be a bit of a challenge if I discover that the breather lines are tough to disconnect from the old purge valve and if re-connecting the breather lines to the new purge valve are tough (because I'll be reaching under the intake manifold to do it and may have to feel my way around without a complete visual as I disconnect/re-connect breather lines). But, removing the air filter housing seems to easier than removing the intake manifold. I just wanted to confirm with someone who had done the work before on the same model of vehicle [before I start taking things apart].
 
#8 ·
After removing the air filter housing, the fuel tank venting valve is located right under the front corner of the intake manifold directly behind the power steering fluid reservoir. See the bottom picture on page 113-7 of the Bentley manual. According to TIS 13 90 500, (1) disconnect the electric plug connection on the front of the valve, (2) release the bottom vent hose by pressing the locking bar and detaching, and (3) detach the rear hose from the venting valve. You might have to loosen the reservoir retainer and move the reservoir out of the way so you can get to the rear hose connection.
 
#9 ·
Thanks a bunch NoVaDrier! I appreciate the detailed information. I'm glad that my plan wasn't that far off. Yeah...it looks like I may have to also loosen the power steering fluid reservoir retainer and move the reservoir out of the way to get to the rear breather hose connection.
 
#10 · (Edited)
Just a follow-up update after I replaced the EVAP purge valve (a.k.a. fuel tank breather valve) on my 2002 BMW 325i (E46). As I did it, I discovered that all that needs to be removed is the air filter housing in order to get access to replace the EVAP purge valve. It turns out that I didn't have to loosen the power steering reservoir retainer and move it out of the way. There is enough slack in both fuel breather hoses that you can slightly unhook the purge valve from the mount and slightly pull it out from under the engine intake manifold.

Before I started the replacement work, I first disconnected the negative terminal at the car battery to kill power to the car. Then I began work by removing the 2 bolts holding the air filter housing with a 10mm socket. I also had to unclip the 2 metal clips holding the round air intake boot to air filter housing. After I unclipped the clips, pull the round intake boot from the housing. Separate the other plastic retangular-shaped intake on the opposite side of the top portion of the air filter housing from the housing by squeezing the plastic retangular-shaped intake as you carefully pull the rectangular intake and the housing apart. There is another plastic rectangular air intake connected to the bottom portion of the air filter housing with a grey foam seal around the inlet; I left this air intake connected to the air filter housing. Now, I carefully lift out the whole air filter housing. After I removed the air filter housing, I just followed NoVaDreier's instructions (previous posted message) for the EVAP purge valve replacement. I've cut-n-pasted and italicized his instructions below:

After removing the air filter housing, the fuel tank venting valve is located right under the front corner of the intake manifold directly behind the power steering fluid reservoir. See the bottom picture on page 113-7 of the Bentley manual. According to TIS 13 90 500, (1) disconnect the electric plug connection on the front of the valve, (2) release the bottom vent hose by pressing the locking bar and detaching, and (3) detach the rear hose from the venting valve.

A couple of footnotes...in order to separate the electric/power plug connection from the purge valve, there is a small metal wire clip I had to depress. The plug connection slides off the purge valve easily when the metal wire clip is pressed. Also it helps to apply a little Vasaline petroleum jelly to the plastic hose barb of the new purge valve; the breather hose slides back on the new purge valve easily if you apply a little Vasaline. After I completed the replacement work and reconnected the car battery, I also used a handheld OBD-II code scanner to erase/reset the old purge valve error code from the vehicle computer. The "Service Engine Soon" indication disappeared and the OBD-II scanner showed zero error codes which hasn't re-appeared. That's great news!

Tools I used:

- Ratchet with 10mm socket (used to loosen/re-tighten nut on negative terminal of car battery and to remove/re-install 2 bolts holding air filter housing to the top of the front driver's wheel well)

- Flat head screwdriver (used mainly to assist in unlatching the 2 metal clips holding air filter housing to the round intake boot)

- Pliers (used to pull the larger breather hose off from old EVAP purge valve...I'm talking only about the hose without the plastic compression clip on the end. The other breather hose with the plastic compression clip can be disconnected using your bare hands)

- Vasaline petroleum jelly (applied a little to the plastic hose barb of the new purge valve...it made sliding back on the larger breather hose to the new purge valve much easier)

- Actron PocketScan OBD-II Code Scanner (used to erase/reset the initial purge valve error code from the vehicle computer after I replaced the valve...the "Service Engine Soon" light turned off after reset it and it never came back on)

- Evaporative Emissions (EVAP) purge valve [BMW lists the part as a Fuel Tank Breather Valve...part# 13901433603] - approx. $80 from the dealer
 
#12 · (Edited)
I didn't have any luck either finding the purge valve replacement part online. So, I bought it from the parts department at the local BMW dealership. They have it listed as the "Fuel Tank Breather Valve" on their parts list database at the parts department. It is $80+ without the BMWCCA member discount or $70+ with the BMWCCA member discount.
 
#14 ·
Not sure who you are mocking on this thread, I merely asked where the part was purchased as the MIL triggered last night at 11PM and I have been at work all day. I looked online to determine the worst case scenario (replace) however will diagnose tomorrow to determine if the part is at fault vs. something else. And yes, I have seen your threads about how to diagnose the part on the car.

I dont have the luxury of your job with an abundant of tech's, diagnostic equiptment and part's available to repair as soon as the problem comes up. Remember, their are many people here that are using the forum as a tool for information gathering rather than mocking threads.
 
#15 · (Edited)
jbeurotech, this thread is just about how the malfunctioning EVAP purge valve on my car was replaced which resolved the PO444 fault code in my situation. In my situation, it was a solenoid that went bad on the purge valve [which seems to be a likely culprit of the PO444 code from the feedback that I've heard from a few other customer-oriented BMW service professionals]. Certainly the PO444 fault code could possibly be other issues such as loose wiring, relays/switches, etc. Some of us posting on this online board are spare time DIY'ers and not professional techs like yourself that do this everyday. Your comment about testing before you replace the part is a valid point. But, I believe that I speak for many on this board, that mocking people is not in the spirit of this board. Being a professional tech yourself, perhaps you can contribute to the posts with more detailed and helpful information about what to test, how and where to test, and with what kind of testing tool you recommend using {if you've already posted on the subject of testing for this fault code and situation, posting the link would be helpful}.
 
#16 · (Edited)
Sorry if it was offensive but replacing a part just because a code said so is stupid! I have posted many times how to test the part to make sure it has failed. I have even posted how to test it with DIY tools. I can do a search for you but I know I have posted at least two times how to test this part. I DO HELP on this board and sometimes my posts are not the most politically correct BUT if you ask for help I will help if you ask to replace a part that you don't know where it is on the car and want to replace it because of a code I KNOW YOU did not test the part. Another member mad e a valid point about the breather line may be broken or have a small hole in it going back to the tank and you dismissed him and said that NOT YOUR ISSUE how do you know if you didn't test. This is were my comments came from. It was not ment as an attack on you just the procedures you used to make this repair.
 
#23 ·
I can agree with this point which we should all not. Usually a service technician would not use a forum to help people rather than just referring them to a service center or stealership so you must be commended for that.

And I agree that one should NEVER just take a P code and use it to replace a part for any reason, upon research their is many instances which could be used as examples why this would be bad.

This forum is supposed to be used to ask questions related to problems so others who have experienced this same symptum can provide advice. It would then be each persons responsibility to decide which direction to take.

I will diagnose this issue in the am and try to determine which avenue to take. I am a little bummed that only the dealer offers the part if it needs to be replaced though was my only point in the earlier thread and hoped someone else had found another solution if it comes to part replacement.
 
#21 · (Edited)
OK, jbeurotech, you've made your point about testing prior to replacing. But, help me to understand how a hole in the breather line and/or loss of vacuum somehow in the breather line is going to cause a "PO444 - Purge Valve Circuit Open" fault code? An open circuit usually means a break in the continuity of the power/control wiring.

Have you come across situations when the PO444 fault code was caused by the loss of vacuum in the breather line?
 
#22 ·
Yes I have the computer in relatively stupid... It activates the valve and if it does not see the right flow it sometimes ASSumes the valve is electrically shorted, now MORE often than not that code is a dead giveaway to the vavle being faulty, if it test good with the outlined test I posted before then you should look elswhere. If everything elsewhere checks out then you may just have an intermittent short in the coil of the purge valve.
 
#24 ·
jbeurotech, thanks for your expert insight, feedback, and for tracking down your previous posts on the subject. I know the next time I get the purge valve fault codes to first test per your advice. I guess I was fortunate this time that it happened to be the purge valve and replacement resolved the fault code.
 
#25 ·
ScoobyBoo, congrats on replacing your purge valve / breather valve on your E46 based on the P0444 code. I also had the same error and the best advice I got was from 2 certified BMW mechanics, was to not waste any time doing diagnostics on this part since the probability that the purge valve / breather valve is bad is over 85%.

When I posted this problem on this forum (1.5 years ago), there was not enough information on this, but the only advice I got was to test valve, which I was not familiar with and not interested in doing.

I have been driving with P0444 error for over 1yr and will replace breather valve soon. Thanks for instructions on how to proceed.

Take care...
Sergio
 
#26 ·
Sergio, thanks. Just for your information...it took me about 1 hour. But, it was because it was my first time and I was planning, confirming my next steps, and doing things cautiously...maybe too cautiously (even with the very helpful feedback that received from the other people on this thread). I can see someone replacing it in 30 minutes [or less] who has done it before. Let me know if you have any further questions once you start getting into it.
 
#27 · (Edited)
ScoobyBoo,

I finally had time this weekend to see my mech friend who does some BMW side work, and amazing, it took him 15min to replace part. He removed air filter housing, and pulled a few times, to remove the purge valve. It took him a total of 10min to do. Another 3min to reset check engine code. While he had air filter housing out, we also replaced day time running lights (H55??) on driver side.

He mentionned again, at BMW, noone has time to diagnose parts, they replace them. They diagnose only if problem still exists after replacement. For purge valve / breather valve, it seems to be a common problem for cars that have high mileage and 6+ years.

Nice to see no check engine light on my dash. It feels good in my head, but do not notice any difference on car performance. I probably was consuming more gas.

Take care...
Sergio
 
#28 ·
I have tried to disconnect the evap purge valve on my 2001 330i, but got stuck with the bottom hose, can't remove it. Bentley manual states "(2) release the bottom vent hose by pressing the locking bar and detaching". There is a plastic clip that seems to be holding the bottom hose connector in place, do I have to remove it? Do I simply pull the hose off the valve? I don't really want to break off anything...
Please help
 
#29 ·
jbeurotech,

Just have a few questions and wanted your advice. I have a 2000 328i and was driving on the highway (twice) and all the sudden the engine would stall completely when shifting to neutral. I ran a diagnostic and two codes came up P1478 (EVAP Capillary Leak 0.5mm detected) and P0440 (Functional Check Purge Valve). Just wondering if one or both of these codes could cause my car to stall without warning. Also, 5 years ago I had a similar problem and the dealer replace the idle control valve. Can I eliminate the idle control valve from the list, since I didn't get a fault code for it?
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top