that's what happend my old one wasn't working at all, i never noticed it and/or thought to check it. so when i put on the new one i noticed it started to fuel cut and the wideband was looking wierd...it blew on my way to the shop were i was going to get it fixed, it was just my luck

 

So let's recap

-You installed a new BOV, saw massive boost spike, but didn't bother to do anything about it
-Your grammar makes you look like the Joseph Stalin of the English language

Did I miss anything?

 

u missed teh buttsecks

 

Fixored

 

Heh, I think my posted was deleted. Similar in content to Savington's.

 

he does not have a external wastegate... and i believe his boost controller is not hooked up?

 

 

I dont see where your blow off valve blew your motor.

1. The turbo blows into teh charge pipe
2. The throttle plate closes
3. Vacuum on the head side of the throttle plate opens your BOV
4. The pressure in the charge pipe vents or recirculates through the BOV

I highly doubt your BOV had anything to do with the catastrophic failure of your bottom end. I suspect repeated abuse on lousy oil or oil pressure or just old parts.


But back to 1.8t Vw's. I thought I was going to surprise one in my 2.3T Ranger running 18psi from a light. Long story short, he was ready for me and I couldnt get around him.

 

when you has turbo and the air goes out the bov if it is broken, the bov will suck in air and overboost the pistons.

Also, peeps.

You've got a 2.3t ranger? Needs moar 16v volvo head.

 

whhhhaaat? so you are telling me that if my bov valve is leaking then it will cause me to overboost? I would say that if someone was messing around with vacuum lines and accidentally disconnected the wastegate then they could blow their motor that way. He also says he turned up the boost. Possibly the mbc stuck closed? if this has been covered in this thread already, please ignore me, i dont feel like reading the whole thing. Also, why the hell would someone bring an old thread back for two smiley's?

 

I agree. If the BOV is leaking, it would suck un-metered air at best. Overboosting isnt really an option.
Locked open, it lets out the boost and will run really rich and run like poop. Off boost, it will suck un-metered air going lean and run like poop.
Locked closed, he'll call teh turkeys with the air stopping the impellor, but the car will run fine.
If his boost controller malfunctioned and allowed overboost, then I can understand the bottom end blowing out.

 

i should have added a smiley. I was just kidding as to how little sense it makes to blame too much boost on a BOV. only way a BOV would cause a problem if it were to be stuck open and if you were really dumb and end up overspinning it

 

over spinning what?

 

overspinning the turbo. With no pressure to activate the wastegate, the full exhaust pressure can spin the turbines to a very unhealthly speed. Make sense ?

 

Guys I think the problem is his old BOV leaked, causeing a boost leak, causeing him to have to crank up the boost control.

He then puts on a working BOV, no more boost leak. The car proceeds to overboost and blow up.

 

But that's not what Slo said. He said having a stuck open BOV would cause the turbo to overspin (which we know isn't right so I assume he misspoke).

I think we all know the consequences of not having a proper signal line to the wastegate. Did you really feel the need to ask "make sense?"

 

If the BOV was stuck open wouldn't the turbo overspin because the wastegate actuator wouldn't see enough pressure to open the wastegate? I have a friend who blew up a turbo on his rb20 240sx and his explanation was a boost leak at one of the couplers caused the turbo to overspin.

 

I'm sorry... I was not clear at all with my previous post. BoostCreep is correct. Wes65 is correct. Slo is correct(except post #69 which was a joke).

The act of compressing the intake charge is what provides resistance to the compressor wheel and limits RPM of the turbo. If your BOV is stuck open or you have a coupler pop off, you run the risk of overspinning the turbo if you keep your foot to the floor as there's nothing to limit it's speed... providing the hole in the charge system is big enough. It won't spool or make any boost, it'll just spin faster and faster until something fails internally. A coupler completely popping off might do it... a stuck-open BOV might also do it. If you are making any boost at all, I doubt you would overspin the turbo (I could be wrong). I think I remember something along the lines of 150k RPM is about the limit of a modern turbo.

What I intended to say was that we all know that wasn't the case here. Whatshisname didn't blow his turbo at all due to anything... he blew his motor because he clearly has money to waste on such things.

 

Please dont take offense, I only meant to be helpful as some folk dont know. As I'm new here, I dont know who knows what.

 

Well i know for sure the bov wasn't stuck open because when ever i reved didn't blow enything out, but what samnavy said is the best answer to what might have happened to the car.