MAJOR PROBLEM: HKS SQV2 BOV, Need advice from people running BOVs!

 

Hi there,

 

I installed 2x HKS SQV2 BOV today.

 

I bought the universal kit so I had to buy 2 caps at the hardware store to plug both holes from the air inlet pipes where the stock recirculation valve were spitting back to the intake.

 

I bought all brand new clamps for the installation. The universal kit also comes with the hose adaptor for the vacuum that goes on at the back of the bov. It The large side fit the OEM hose, then I added a vacum a bit smaller that connect to the BOV nipple.

 

I made sure that everything was very tight and nothing was moving. I added zip tie and a clamp on each vacuums.

 

Then I reinstalled the fan, the T form the intake, the JWT pop.

I started the car, let it warm up for about 10-15 mins, then I took it for a spin.

 

I accelerated on the street, changed gear and pshhhhhh what a nice sound! It was like a symphony to my ears. Then I realized that every time I was giving more gas and releasing it, the idle would jump from 500 RPM to 2000 RPM back and forth. The car was almost stalling, and it got worst and worst. The idle was very unstable, I just made it home. It also did 2-3 backfires on the way back. I was pretty upset since I must have spent over 500$US for this kit, and the extra parts (caps, clamps, zip tie...).

 

I took everything apart again, made sure there was no vacuums or hose that popped out. Everything seems fine but I reinstalled both of them just in case and made sure everything was tight. Then started the car and died almost right away, the idle was very unstable.

 

I checked to see what happens when I gave him some gas. The left BOV is spitting alot of air and the right BOV isnt spitting anything. Also even on idle, without giving any gas the left BOV seems to be releasing air.

 

I thought this is probably a defective bov. It shouldnt release air under no boost condition. That probably created a huge vacuum leak and killed my idle and air fuel ratio which led to the backfire.

 

I will be contacting HKS for a replacement and see what they says. I then reinstalled the original Nissan OEM recirculation valves. Took the car for a spin and everything is running great. No problems at all.

 

I would like anyones feedback about this to make sure the problem is the BOV. I did alot of research and saw many post saying that BOV spitting in the atmosphere will mess up your Air Fuel ratio, you will end up running rich and it can backfire.

 

Is there anyone here that installed some BOV and didnt have any problems at all? I am hesitating, if its gonna make my car idle unstable, they are not worth it at all, and I should probably resell them once I have my replacement bov from hks.

 

I just want to see if anyone that have some BOVs have any problems like that or if all those issues should be related only to the leak from the bad BOV I installed.

 

I also saw that HKS was selling a module HKS EIDS to make your idle more stable when using a BOV. Is it really necessary? Anyone tried it?

http://www.hksusa.com/products/?id=2175

 

I saw that HKS also sell an adaptor to recirculate the air to the stock intake. Its just a fitting to install on the SQV2 bov, and you can then re attach the piping to the intake tubes. Did anyone tried that? would that be better for the idle problems? When they recirculate the air, that probably kills the nice pshhhhh sound. So it makes them pretty much useless and it would be best to stick with the oem valve.

 

Please help and share your experience with BOV,

thanks

Where's FunkySi when you need him? Best advice on BOVs is here http://www.twinturbo.net/ttnetfaq/FAQpages/bov.html

And you said it yourself:

pretty much useless and it would be best to stick with the oem valve.

as soon as my bovs went on mine did the car did exactly the same, cleaned the AFM to no avail, turned out it was temp sensor, not sure if it was in any way related to the bovs though!

It can be as simple as adjustment,try winding the screws down on top(if they have them!)-if no screws you need to shim the spring. :)

i fitted 2 x hks ssqv bov's iv had no probs at all and they been in for over 2 years. may be faulty bov. try replacement.

The earlier hks bov's had leakage problems, so if they are the earlier ones keep an eye on them?

I have the HKS SQV's too have no problems with idle but only get a slight pff just like a womans fart when i come off the gas or change gear at full boost, but get a much better ptsssh when i change gear at a lower boost pressure. Have no adjuster on the rear so prob going to have to strip and shim.

 

You would have to rev the nuts out of it to get the bov's to work when not driving anyway so not a reliable way to tell, but if 1 is leaking i would say thats your problem with the idle as its acting like a boost/vacuum leak

ok great

Thats what I assumed, that BOV should not leak air when idling. That was creating one huge Vacuum leak and messing up my idle.

 

I know BOV are not really useful but the main reason is to get ride of that Goose Honk. Its not the nicest sound, and its so annoying every time I hit 4000 RPM.

 

The HKS SQV dont have any adjustment screws on them, it should be a direct fit. I have the latest style 2007 SSQV2 that came out a few months ago.

 

Did anyone tried aftermarket BOV like HKS or any others and use them with the recirculation kit? Can you still hear any sound when shifting? Does it get rid of the goose honk?

 

Also I was wondering if that HKS electronic module is really necessary for the Air Fuel ration. Did anyone tried it? It would be great to hear some feedbacks.

 

Maybe that would fix your woman farts issue CarlZ, that must be because when you drop the pedal, the ECU gives more fuel for the air that is releasing, but since you dont have your recirculation valve on. Your A/F ratio gets very rich, which cause these flatulences. That HKS module is suppose to change your MAF values to compensate and keep the ratio even.

 

thanks

the hks is designed to do a minor boost dump at low pressures

 

The Super SQV is engineered to initially open the small primary valve at light throttle and load conditions, then sequentially opens the secondary valve for additional relief capacity under high boost and load conditions