wastegate stuck closed?

[blakkat]

hey guys, so the guy who had the car before me had a boost controller on it. I noticed it was boosting to 21 psi so i removed it and ran a straight line from the j-pipe to the wastegate. it is still boosting to 21 psi. so is it safe to say my wastegate is stuck shut?

also figured i would mention where the gauge is T'd into is the vacuum line on the fuel pressure regulator if that makes any difference.

 

[undefined0000]

hey guys, so the guy who had the car before me had a boost controller on it. I noticed it was boosting to 21 psi so i removed it and ran a straight line from the j-pipe to the wastegate. it is still boosting to 21 psi. so is it safe to say my wastegate is stuck shut?

also figured i would mention where the gauge is T'd into is the vacuum line on the fuel pressure regulator if that makes any difference.

Seems like its stuck closed. The gauge is tapped in probably the best spot. I would try to unsieze the wastegate. You might be able to move it by hand. Boost leaks could also cause that spike. Is the 21psi constant or just a spike?

 

[blakkat]

pretty constant, car is on a catless downpipe. but i dont think it should creep all the way to 21psi on wastegate spring pressure. tried moving it by hand but it wouldnt budge

 

[dsmcurse]

it been awhile since ive had a stock intake mannifold but i can remember getting my boost referance line completley by its self and no tee fittings. if i remember correctly the big barb that was once pcv was my bov, breake booster hose stock location, one barb only for boost referance (smalllest nipple on plenum) and one straight to the fuel regulator. none of that emmissions crap really mattered to me

and no mbc just straight line from turbo to wastegate should be like 10-12psi. i would say something is wrong. try to manually pull the flapper open with a pair of pliers. maybe this will loosen things up and it to start working correctly

 

[blakkat]

yeah im gonna try a little harder to move it. or maybe pick up a new one on extreme psi before i run this engine lean and blow it up. its still on a stock fuel pump. i dont think 21 psi is doing it any good

 

[NHerron]

What turbo are you running. If it's a 16G, paired with a nice 3" catless exhaust, that is normal for the 16G's, the wastegate just doesn't bypass enough gases (on the 16g's) to slow down the turbine causing an unintended overboost. If you toss in a catatlytic converter, the added backpressure should do ya and you'll be able to control boost again.

Or just shift before it hits 21psi, it's what I do.

 

[undefined0000]

What turbo are you running. If it's a 16G, paired with a nice 3" catless exhaust, that is normal for the 16G's, the wastegate just doesn't bypass enough gases (on the 16g's) to slow down the turbine causing an unintended overboost. If you toss in a catatlytic converter, the added backpressure should do ya and you'll be able to control boost again.

Or just shift before it hits 21psi, it's what I do.

^ That actually reminds me, I have a catless and basically mufflerless 2" exhaust with a 16g. Probably explains my 15psi.

Ultimate test is to rev the car in neutral and have someone watching the gauge to 13 psi, you'll see the wastegate flapper open (awesome thing to see) if not, its definitely stuck. If it opens and boost still climbs, its exactly what the guy above is talking about.

 

[NHerron]

15 psi sounds pretty normal WG pressure maybe a tad bit but IIRC the spec is 12-15psi?

Can't really rev in neutral and make any boost, you'd have to put a load on the engine to make anything.

 

[RyeDawg]

Take the vaccum line off the waste gate. Take a blowgun, Set the regulator on the compressor to 15 psi. That should be sufficient to make the watergate open.

 

[007jimmy]

ive had to fix a few wastegate flappers that came out of alignment. if you cant move it by hand then i would say its time to drop your turbo and see whats up with it. usually just takes a few good smacks with a hammer. The sleeve tends to move if it isnt adjusted properly.

 

[undefined0000]

15 psi sounds pretty normal WG pressure maybe a tad bit but IIRC the spec is 12-15psi?

Can't really rev in neutral and make any boost, you'd have to put a load on the engine to make anything.

I've also just revved with e-brake, but don't know how bad that is. With the e-brake, the car will creep forward a little, so I think it simulates load.I do it when I want to show off.

 

[NHerron]

What I say on that is next to a grain of salt but on auto I know some people do it at the strip but it's hard on the torque converter and shouldn't be held long. Manual I can't see it really happening except slipping the clutch and going through them every other month

Jimmy, you shouldn't be able to move the actuator by hand since it's spring loaded. Or are you talking about taking the actuator off and moving the flapper itself

 

[blakkat]

sorry guys didnt expect such a quick response. its a 14b turbo. with some no name full downpipe back 1 pieces exhaust. not sure on diameter but i think its a 3inch. also guy before me had it chipped so it has lc set at 3800rpm so kinda hard to build a lot of boost sitting still, but i suppose that makes sense it should still move right?

 

[undefined0000]

sorry guys didnt expect such a quick response. its a 14b turbo. with some no name full downpipe back 1 pieces exhaust. not sure on diameter but i think its a 3inch. also guy before me had it chipped so it has lc set at 3800rpm so kinda hard to build a lot of boost sitting still, but i suppose that makes sense it should still move right?

2 Step would work. Get some ear plugs though!. You could sit and 2step it up to build boost and the flapper should open. a 14b making 21 psi seems like a bit much

 

[96awd16g]

A 14b shouldn't be boost creeping that high IMO. Make sure the hose going to the wastegate actuator isn't plugged, cracked, loose, etc. Remove the wastegate actuator rod from the flapper and make sure it moves freely. If all is good, test the wastegate actuator with an air compressor as already suggested.

 

[blakkat]

i have already taken the arm off, and the flapper moves just fine. i wish i would have thought about that today when i was at school. but we have shop lines that dont have a regulator so im not sure how i would pressurize it to a specific pressure.

 

[96awd16g]

I certainly wouldn't test it with 90 psi.

 

[blakkat]

turn the wga arm into a harpoon. ill try tomorrow and let you guys know the outcome.

 

[JusMX141]

pretty constant, car is on a catless downpipe. but i dont think it should creep all the way to 21psi on wastegate spring pressure.

You're driving around on a catless 3" open downpipe? You have boost creep. Confirm this by removing the actuator arm from the turbo and taking the car for a drive doing a couple hard pulls. If the turbo's still making 20+ psi with the actuator arm removed, you have your answer.

 

[blakkat]

no its not open downpipe, the guy made the whole exhaust a 1 piece all the way to the back of the car.

 

[JusMX141]

Still....do the test I just posted and you'll confirm whether the actuator is working without firing 90psi into it and ruining the diaphragm if it doesn't have a hole in it already.

 

[blakkat]

Still....do the test I just posted and you'll confirm whether the actuator is working without firing 90psi into it and ruining the diaphragm if it doesn't have a hole in it already.

yeah, ill do that tomorrow. i didnt think of it that way. thanks

 

[blakkat]

Yeah the wastegate is stuck closed. Tried it with the flapper disconnected and couldn't build any boost at all

 

[96awd16g]

Now you need to know why. Lines plugged, wga is bad, or lines leaking.

 

[JusMX141]

Actuator likely has a hole in the diaphragm. Look in the classifieds or on eBay for a used replacement....if you're looking for something new, this would work great:

http://www.dsmtuners.com/forums/vendor-announcements/448851-stock-fitment-dsm-18psi-wga.html