Posted in the stupid questions thread, too, but I have an L500 Daihatsu with a weird problem. It’s new to me and the previous owner was a teenager who put a large blowoff valve on it. I think it may be set too soft. What’s been happening is that it will build boost quickly and inconsistently, incongruous with my speed, before blowing off then cutting power for have a second, and lurching my car. I’ll start, drive, shift, bov psh, drive shift psh. Drive, give a but more throttle, then pssh without my lifting off the throttle, followed by a second of lurch and power dropping significantly (if I clutch in at this point I can clutch out and resume driving fine)I’m finding it’s not really “holding” boost at speed, but rather pshpshpsh blowing off on its own. Do I need to just stiffen my BOV? I have the original plumbing and that’s going in, because stock is always nice, but until that point how can I avoid fucking my car up? L500 daihatsu with the EF-RL engine. Engine pic related. I will soon have the original recirculator unit on, but until I get a rain-free weekend, I gotta live with the >PSSSSHH
>>28676734I’m a moron and obviously meant “car” in the title lol, unless anyone here is into CAD which isn’t outside the realm of possibility
>>28676735It's cool, we get it. And yes I've spend many years doing CAD.It could be the lack of recirc fucking it up, the BOV may be set too low, or your wastegate is set too low or busted. Or else you've got a vacuum leak in the system somewhere. Probably the BOV. I can't say specifics as I've only run stock ones w/ rescirc.
You need a BOV restrictor or get rid of the BOV altogether.
>>28676786I agree. Thankfully I have the original plumbing to fall back on
>>28676738if you have a mass air flow sensor then you will absolutely have drivability issues if you vent to atmosphere, i dont think i have ever seen a non recirculating oem setup. see if you can plumb the bov exit to somwhere ahead of the compressor but behind the maf. wrenchlet.
also meant to tell you its shitting itself because your BOV is leaking
>>28677098Not a wrenchlet, just never had a turbo car. I’m excited to get into it and replace the recirc unit
>>28676734Dont you have a smaller picture, anon?
>>28677158Can only find nipponese sized pictures online, I can post my engine bay if anyone cares
Bmup
>>28676734Just adjust the bov until it holds boost, should be a set screw over the diaphragm cover.
>>28678384I had to pretty well adjust the BOV to the hardest setting to get it to hold boost, and even then it still cut out at one point; same story of driving fine, then after a gear shift failing to hold boost, couple with a forced blowoff and instant deceleration/loss of power for no more than a second. That said, it only happened the once so it could be a blip. I don't believe I'm fighting compressor surge here as it's a ridiculously tiny turbo.
