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Have just put a blowoff valve on my R33. Its an atmospheric one (not too loud thank christ) but now everytime i pull up at lights etc, it stalls. Why does it do this and how do i fix it???

Please help or the BOV has to go!!!

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hey Brad,

this is a known common problem for atmo bov. I have a similar issue with my hks ssqv bov, i found that the return line that goes to the pipe that connects the afm to the turbo was leaking, so everytime i stop it would stall or almost stall. make sure that the return line is block and not leaking. Also does ur bov have any adjustment? as sometimes it can be too loses

Its because your running an AFM. The BOV is venting air thats already been measured so your car is running excessively rich and stalling.

Only way to solve it is to get a MAP based ECU or plumb that sucker back.

negative >_<

im running atmo bov with afm and it works fine :(

i've had 3 different bov with stock ecu no problem...

got a hks ssqv in mine haven't had really any stallin problems if ur driving a manual just change gears faster:P although ma bro in law has a ssqv on his 33 n he said he's had problems when he's like driving 70 it would even stall then

btw wot type is it? as if u have a ssqv they make recirculation kits for them to turn them into plumback:)

Hey mate just pop into Clark rubber and get a rubber chair stopper to block off your return pipe, works like a charm as suggested by someone on the forum. No stalling problem with my hks ssqv only bad thing is petrol has gone down hill haha so stockie might go back on soon when I can be bothered.

Try wind the idle up a little bit, like has been mentioned it's a very common problem with atmo's. The stock ECU is tuned to see the return air and I also think the stock BOV is designed to leak slightly at idle. Most people just wind the idle up to like 1000rpm and it's fine, some people just have non stop problems with them. My car never stalled with the R2D2 but it idles at 900-1000rpm.

My car's a manual. The blow off valve is some cheap chinese copy (yeah i know, serves me right) lol

Will be getting something better like a GFB or TurboSmart etc.

To cut a long story short, the best way to solve the problem is to have a plumb back?

However plumb back does not make the woosh noise?

Its not my idea by the way, my wife wants it to make the noise lol if it is going to cause problems, or premature turbo wear etc ill probably put the stock one back on.

when you install an atmo valve, make sure the return valve is sealed up, and if it's stalling when coming down to idle, try and adjust the valve a bit tighter... that way it will close sooner and it should hopefully fix your problem.

However, if you are giving it crap, you may experience backfiring on gearchanges etc as the car will run rich every time the BOV vents.

It already backfires and pops on hard, high rev gear changes lol

Is there a way to stop it running rich? Running it rich wont kill the engine will it?

While these questions seem dumb, i have never played with skyline engines. I know them very well underneath (Suspension etc) but never done anything under the bonnet lol

mmm ive had a problem like this

the return pipe to the intake pipe has to be blocked off

if the cars still stalling afterwards the revs are to low on idle so you gotta adj it on the back of the plenum which there is a screw

once the idle revs are fixed and car still stalls

your blow off valve spring is shit

and for running rich who cares its fine atleast its not lean and pinging

mmm ive had a problem like this

the return pipe to the intake pipe has to be blocked off

if the cars still stalling afterwards the revs are to low on idle so you gotta adj it on the back of the plenum which there is a screw

once the idle revs are fixed and car still stalls

your blow off valve spring is shit

and for running rich who cares its fine atleast its not lean and pinging

yeah some bov just dont work lol :pirate:

mate some people have no idea what they are talking about i have an auto skyline first mod ever done on it was an atmo bov (not anymore now plumback) but when i did have it, i bought a turbo smart one which comes with the plug to block the plum back pipe, never had a single problem with it at all... still had stock air box too

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