BPV or something else?

[MShreve]

I've noticed that whenever I install my Forge BPV I get a really rough idle and minor exhaust popping whenever I start the car (cold or warm). It sorta mellows out after a bit but never goes away completely.
I originally thought it was just my TP and had somehow never noticed it before. But over the last few months I've been doing a lot of tinkering, swapping parts back and forth and logging with a DH. Whenever I install the stock BPV the car idles fine, but every time I put the forge back on (with any combination of yellow/blue spring and 1-2 shims) it starts popping and idleing rough again.

Any ideas what this behavior could indicate? Should I just ignore it? I'd much rather run the Forge after looking at logging as it's holding pressure higher and longer, but I also don't want to damage anything because I don't know any better.

I don't have any leaks and I don't get any CEL's in either (any) configuration. I've also been disconnecting the battery between each test and putting 80-100 miles on before logging and doing the next swap.

Thanks for any input and/or links if this has been discussed before.

 

[USAFVMI08]

How long have you had it on the car? It might be leaking. Try taking it apart and rebuilding it and make sure you regrease everything. See if that helps.

 

[MShreve]

I pulled it apart before putting it back on today since I had it apart to add some shims anyway. It's still full of that thick red grease and the O ring looks brand new. It only has maybe 1000 miles on it.
I've been running the stocker quite a bit recently because of frequent dealership visits (unrelated problems).

 

[USAFVMI08]

Hmm. I'm not wondering if it's not seating right on the intake pipe or maybe not a good seal around it. If you have the time, have some one rev up the car with it installed and put your hands around it to see if you feel any air leaking.

 

[MS3 GT]

go for a BOV

 

[1quickturbosix]

Are you still running the stock clamps from the stock bpv on the new forge? Try replacing them with appropriate size hose clamps and see if this helps. Could be just enough leakage to generate this problem. I know when i installed my forge and used the stock hose clamps they would slide right off, and I wasnt having that. Its a cheap fix if that were to be the problem.

 

[Blendercloud]

It sounds like that vacuum hose that goes onto the top of the valve is loose or leaking.

 

[GoFast]

go for a BOV

lol did you read the OP at all or just the title?

 

[MShreve]

I've been using hose clamps since the first time I installed the Forge. Like you said, the stock clamps don't fit the forge very tight.

I'm also using washers on the bolts that hold the forge on, as I noticed the bolts bottom out before completely compressing the O-ring. But that didn't make any difference.

I just finished re-checking all the hoses and connections. I also had my wife hold the engine at 4k rpm while I snooped around under the hood, but I still haven't seen or heard any signs of a leak. Wouldn't a leak cause a check engine light?

I'm going to take the forge apart again tonight for a closer inspection to see if I can find any indications of leakage past the seals.

 

[1quickturbosix]

Wait? the bolts are bottoming out? That seems odd.

 

[1quickturbosix]

Not sure on the legality of this but im gonna try it anyways. Sorry if this offends anyone but just trying to help.

well that didnt work, Thers a nice write up on servicing your forge over on msf.

 

[1quickturbosix]

Alright,,, I tink I have this figured out. NIce little write up on servicing the forge

 

[USAFVMI08]

You are using the bolts that originally held the stock BPV on, right? That's what I used and I didn't have any issues.

 

[Blendercloud]

I didn't have any issues either.

 

[MShreve]

I'm not sure it really would have been an issue, but without the washers I could still slide a thin feeler gauge betwee the BPV and the intake pipe on the engine side. So I added a couple of washers and was then able to cynch everything up tight. I'm pretty sure the gap was because the bolt was bottoming out on that side.

No luck on the Forge. It still looks brand new...no signs of any leakage.

Is there anything else that could cause the rough idle besides an air leak?

 

[Speedkid]

Hks is pretty good.

 

[1quickturbosix]

Did you perform the pen test located on the bottom section of that pdf I attached up there?

 

[USAFVMI08]

Is there anything else that could cause the rough idle besides an air leak?

Gremlins.

 

[MShreve]

Did you perform the pen test located on the bottom section of that pdf I attached up there?

Not yet. I'll try that the next time I take the BPV off.

 

[1quickturbosix]

Gremlins.

+1 on this. Them things will get ya every time! LOL