The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support STM Tuned
Please Support STM Tuned

Stock 2g Blow off Valve not Blowing off after engine rebuild

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

1997_GSX

10+ Year Contributor
714
6
Jul 29, 2008
Keyser, West_Virginia
So we bought a 95 Talon TSi FWD for $1000 it spun a main and 2 rod bearings. We bought a new 2g OEM Crankshaft, Rods, pistons, rings, gaskets, timing belt, balance shaft belt, and made a custom manual timing belt tensioner.

Well after a bit of trouble with the crank angle sensor being busted, we bought a 1g Cam angle sensor, wired it up good; soldier and the whole nine yards...

It has a MHI Big 16g turbo running off the stock bcs. We ported it to prevent boost creep.

Now it has the stock 2g bov that I know works because it came off my 97 gsx, it is on there temporarily.

I hooked all the vacuum lines and used gsx as a reference, it has never been touched except by me.

Now it builds boost to like 12 psi, let off the throttle and it sounds like compressor surge. We haven't really drove the car hard so this is under medium acceleration.

I don't know what the problem could be. The car was previously owned by a ricer... we have pretty much fixed everything riced out on it...

Any help is much appreciated.

Thanks, Luke
 
Most likely you have a large boost leak somewhere or you have a problem with insufficient vacuum. When the throttle plate closes and the air coming through your piping runs into it and surges back this should increase pressure in front of the throttle plate and you should have vacuum behind it, it is the combination of these two forces (one pushing and one pulling) that will open up a stock bov so if it doesn't work then you have 1. A bad bov 2. Insufficient boost 3. Insufficient vacuum. Check the vacuum line that goes to the bov for holes or tears and perform and boost leak test (use the search button if you've never heard of it).

Where did you plumb the vacuum line that goes to the bov from? Do you have anything T'd off of that line or is it direct to the bov? I'm assuming that you have it hooked up correctly if you followed the vacuum setup of a gsx but lets make sure.
 
Did you connected the vacuum line directly to the intake manifold?? Check the vacuum line if is connected right, it also could have a small tear. I recommend you to buy another blow off valve because stock 2g's bov don't hold boost. A good and cheap bov is the 1g...
 
come to think of it, the kid that we bought it from broke the intercooler mount off the intercooler, my dad just pop rivited it back on... I don't think he use rtv either :( like I told him to. Ill use some windex and look for bubbles with the car on...

Thanks guys, Luke
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top