CAI BOV/BPV Throwing Code?

aceblaster

Member
:
2008 MazdaSpeed3
My car started giving me an engine light a while back. I ran my OBD reader on it and it says it's running lean on idle, and running lean off idle. I haven't had any performance issues other than it feels a little boggy from time to time (a little sparatic and only started about a week ago.) Anyway, the light came on about a month after I installed my turbosmart dual port BOV/BPV hybrid. I don't know if that would cause me run lean, if it was slightly out of tune? Also I have a MS CAI which I know the older version of this part did have this exact problem, but I can't seem to find anywhere that I can see if mine is the older version or the newer version. The CAI has these numbers on it if anyone knows how to tell or where to look. "MS CAI-#D-607-1 and GRMS-8M-L29.

I have also tried to retune my BOV/BPV and then reset the ECU but the codes come back almost instantly, I cleaned my MAF sensor and the light stayed off for a day or so but then came back.
I have read that the CAI may need a Airflow Straightener... Where in the pipe would it be?(where would I look to see if it already has one.) I baught the car with the CAI already installed so never did much with...


Thanks for the help.
 
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straightener

I think it is supposed to be directly in front of the maf...if you dont have one that would be my guess as to the lean condition...all that turbulence sucks. you can get one from jscspeed or one of the sites....10 or 15 bucks, anyways it helped me out alot.
 
Do you have your Tutrbo Smart rununing in 'Recirc mode or VTA'?

I have put it at different spots. I ran it at 3 turns (50/50) for a while then I've ran it at 3 1/2 turn and 4 turns toward soft. (recric) Right now I'm running it at 2 turns (VTA) and still getting the codes.
 
Just run it full recirc. Reset your ECU and codes should probably go away. This engine needs full recirc. PERIOD.

If you do not have the air straightener in the MSCAI then that may also be your problem. You NEED the air straighter. Do a search here and find the source. I think AEM sells them as a separate part number. Don't recall the price, but should be less than $15.

Not having the air straightner will produce a lean condition under certain conditions. But, please do not just get the air straightener and still try to run VTA. This engine, I repeat, needs to run in full recirc mode to have properly matched air and fuel.
 
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Just run it full recirc. Reset your ECU and codes should probably go away. This engine needs full recirc. PERIOD.

I will give it a try. The engine doesn't require full recirc but it is definitely better with it. Plus it's easier on the turbo.
 
Based on ur symptoms, it sounds like the MSCAI is the culprit.

I remember some people were throwing lean codes after installing the MSCAI.
In-fact, Mazda pulled the CAI off the shelves and issued a recall on them because of the ecu throwing lean codes.

I would suggest trying to re-install your OEM air box and see if the problem persists.

I honestly doubt it's the bpv causing your issue.
 
Based on ur symptoms, it sounds like the MSCAI is the culprit.

I remember some people were throwing lean codes after installing the MSCAI.
In-fact, Mazda pulled the CAI off the shelves and issued a recall on them because of the ecu throwing lean codes.

I would suggest trying to re-install your OEM air box and see if the problem persists.

I honestly doubt it's the bpv causing your issue.

Thats what I was thinking too, but I bought the car with the CAI so I don't have the stock box. Does anyone know the success rate on the airflow straightener, or has used one? I think I might just buy one and try it out if not.
 
Thats what I was thinking too, but I bought the car with the CAI so I don't have the stock box. Does anyone know the success rate on the airflow straightener, or has used one? I think I might just buy one and try it out if not.

I heard mixed results..mostly positive from the air straightener.

Personally, i think u should dump the CAI and just go cobb like the rest of us.(drive)
 
I heard mixed results..mostly positive from the air straightener.

Personally, i think u should dump the CAI and just go cobb like the rest of us.(drive)

I would but I just love the sound of the MS CAI so much more than the COBB to give up right away. :) If I can't get it figured out that will definitely be an option though.
 
^^ or if you really love the sound of the CAI you could get a cp-e that has the air straightener. I'm running one now with a SSQV. The SSQV was VTA when i bought the car, and is now recirculated, but either way I got no CELs.

just saying... consider cp-e
 
IMO cp-e is the way to go. they where the first to have a product out that is not trowing codes. Their design is very good compared to aem/mazdaspeed one. i run it since 3 years now and i still like the sound of it. I even used it in 3 harsh canada winters an it look like new(filter have been changed tough).
 
IMO cp-e is the way to go. they where the first to have a product out that is not trowing codes. Their design is very good compared to aem/mazdaspeed one. i run it since 3 years now and i still like the sound of it. I even used it in 3 harsh canada winters an it look like new(filter have been changed tough).

Well the Cp-e and the MazdaSpeed Cold Air Intakes are the exact same, the only difference is the Cp-e comes with the air straightener and the MS doesn't...
So the design isn't "very good compared to the Mazdaspeed one" It is the exact same. I just need to get the Air straightener to fix the problem with the intake.
 
Update-

Checked tubing and piping for leaks today.
Took of the TIP/CAI, The tube going from the TIP to the Boost Control Module was unscrewed a little bit, tightened it up, put it all back to together and still getting the codes.
Hooked up my OBD/Computer to the car and Checked all the fuel Pressures.
Nothing turned up, just a lot of sweat...

Results
-My Fuel pump is Working Perfect.
-No found leaks/defaults in piping/couplers on CAI or TIP.
-Still waiting for Air Straightener to arrive. :(
 
Well the Cp-e and the MazdaSpeed Cold Air Intakes are the exact same, the only difference is the Cp-e comes with the air straightener and the MS doesn't...
So the design isn't "very good compared to the Mazdaspeed one" It is the exact same. I just need to get the Air straightener to fix the problem with the intake.

It is the AEM that is the same as the Mazdaspeed, not the Cp-e. Mazdaspeed simply rebranded the AEM. There is still some false information out there regarding the Mazdaspeed CAI and the air straightener. Here's the straight scoop (which can be obtained by using the search function):

When Mazda first released the Mazdaspeed CAI for the MS3, it did not have the air straightener that was included with the AEM version.

Mazda started getting complaints of CEL's and conducted an investigation. It realized that it needed to include the air straightener.

Mazda suspended sales of what we now call the "1st gen" CAI because those out there on the dealers shelves did not have the straightener.

When Mazda released the new "2nd gen" CAI, it had to go through CARB recertification (which seemed silly since it was identical to the already certified AEM with the same straightener already tested). This resulted in a delay to access.

Now the 2nd gen Mazdaspeed CAI is out and has been on the market for over a year, perhaps a year and a half. It does not throw codes.

Guys like OP who got a 1st gen CAI only need to get the plastic air straightener to insert in the pipe just ahead of the MAF housing and all is well.

There is an orientation arrow on the straightener which lines up with a mark in the tube. The first gen tube might not have that mark. Alignment should look like the attached photo. It ends up with the vanes inside the straightener being at about a 45 degree angle to the MAF sensor. The mark on the straighener should point straight up to the flat part of the outside of the MAF housing, if that makes sense. Just do it like in the photo.

I hope this helps.
 

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It is the AEM that is the same as the Mazdaspeed, not the Cp-e. Mazdaspeed simply rebranded the AEM. There is still some false information out there regarding the Mazdaspeed CAI and the air straightener. Here's the straight scoop (which can be obtained by using the search function):

When Mazda first released the Mazdaspeed CAI for the MS3, it did not have the air straightener that was included with the AEM version.

Mazda started getting complaints of CEL's and conducted an investigation. It realized that it needed to include the air straightener.

Mazda suspended sales of what we now call the "1st gen" CAI because those out there on the dealers shelves did not have the straightener.

When Mazda released the new "2nd gen" CAI, it had to go through CARB recertification (which seemed silly since it was identical to the already certified AEM with the same straightener already tested). This resulted in a delay to access.

Now the 2nd gen Mazdaspeed CAI is out and has been on the market for over a year, perhaps a year and a half. It does not throw codes.

Guys like OP who got a 1st gen CAI only need to get the plastic air straightener to insert in the pipe just ahead of the MAF housing and all is well.

There is an orientation arrow on the straightener which lines up with a mark in the tube. The first gen tube might not have that mark. Alignment should look like the attached photo. It ends up with the vanes inside the straightener being at about a 45 degree angle to the MAF sensor. The mark on the straighener should point straight up to the flat part of the outside of the MAF housing, if that makes sense. Just do it like in the photo.

I hope this helps.

Yes, that helps a lot. I would have probably just thrown the straightener in cricked and been pissed that it wasn't doing anything haha. Good write up though.
Thanks for the info. :)
 
Got the air straightener installed and didn't want to drive for a week to see results so I reset my ECU... CEL stayed off for about 2 days then came back... Does anyone have any other suggestions why my car would be running lean or a better way to check for leaks? Also if there a common place that there is a leak? When checking for leaks I just used carburetor cleaner cleaner and sprayed down the clamps on my TIP, FMIC Pipes, and my CAI. Maybe try and spray down the smaller hoses?
 
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