2002 Passat 1.8T BOV Question...

[Kahulia]

So my girlfriends roommate just purchased the afformentioned car. (2002 Passat 1.8T.) And I've always promised her if she bought a car with a turbo, I would buy her a BOV. And now she has one, so shit, I have to buy her a shiny new BOV. I was just reading on a VW forum that a BOV on a turbo VW engine would cause the engine to run rich and end up with her staring at a CEL. I know thats something she dosn't want to deal with since this is the only type of modification she wants, and only because she likes the sound. So I guess my question is, does anyone know if this is actually true? And if so, is there any kind of CHEAP solution to this problem (MAP sensor trickery perhaps?) that would get rid of the CEL so she could just have a pretty "Pssssh" everytime she shifts on her new Passat?

Thanks,
Matt

[Kahulia]

No one?!

Weak...

[DeCoY]

I think this will work perfectly for your needs. LOL

http://www.sunamiturbo.com/

[Prelude97]

I don't know too much about vw's but I am guessing that they use a MAF sensor and not a MAP sensor. I'm also not too sure about it throwing a CEL but ususally cars with a MAF sensor have the blow off valve routed back into the intake because of the placement of the MAF sensor. With the blow off valve venting to the atmosphere the ECU will usually be adding fuel for the air that was just released into the atmosphere causing a rich condition. Personally I think it will be ok and not causes any problems excpet the car might stall out between a shift if too much fuel is added.

[2002jettavr6]

the 18t motor use a diverter valve not a BOV if you but a BOV on there it will very rich

[john]

http://jsalmi.com/bov/ <-- read this

The 1.8t uses both MAF and MAP.

[Yuikio]

Yep, the VAG 1.8T is a MAF system. So if you blow off air the system has already measured, air which usually recirculates back into the intake tract, the car thinks there is more air in the intake tract than there actually is. So the ECU sends fuel, but the air to combust it with has been blown off, so you have too much fuel=rich=fouled plugs, O2 sensors, maybe even the cat if you do it for long enough.

You could get a hybrid BOV or one of those eBay "electronic" BOV's that is basically a speaker that sounds somewhat like a BOV.

[Kinematics]

Or leave the car as it is and don't worry about causing any issues with how it runs.

[Enthalpy]

No one?!

Weak...
Wow, you are impatient when asking for free help from a bunch of guys that probably aren't on at 11:45 at night.

[stu]

Just tell her to stop being a ricer and drive it the way it is.

[doctorstupid]

Meh, it might cause enough of an issue to bother her, but I drive cars that "shouldn't" use open-atmosphere BOV's everyday without an issue. I've never had any stumbling between shifts, stalling, etc, though some people do run into trouble. A lot depends on the valve quality and driving style. HKS SSQV's are in my opinion the most stable and bullshit-free BOV's out there for a car running a MAF in draw-through. TurboXS and their eBay clones are the damn near shittiest valves money can buy, in any configuration.

The rich condition that the internet is going to scare you about is when you shift gears; however according to the ever so handy wideband O2 sensor, you will only go slightly richer, we're talking 10.8:1 or so for a tiny fraction of a second. SSQV's have a smaller primary valve that'll give you the sound and prevent light load compressor surging without purging enough air to cause an actual rich condition (for most cars), and the secondary valve will purge gobs of air when needed.

[formulanerd]

just throw a new DV on there with CAI, you'll be able to hear the sound without the stock airbox muffling it.

everyone always asks about my BOV, but i run a DV and it's just the charge getting dumped back into the intake tract. it's still pretty loud. but you're not gonna get a whistle, or anything that sounds like the ssqv, just a loud pssssh