Boost leak test good and still very slow boost?

[95EclipseGST]

I have been having slow boost problems or a long time now. I fixed leaks, one by one, and now it will hold air and keep it. So i thought i was good to go and put on a new MBC and everything and go for a drive. Still slow boost. I dont even hit 9 psi until 4500 rpm. So i screw the mbc clockwise tighten, just to see if it spools faster and it does barely, but then boost goes too high after 5k rpm. So i turned it back down. This is an EVO 3 16g and it spins smoothly when i spin the blades. What could this be? Im pissed. Any ideas? Thanks

 

[95EclipseGST]

My vac is 19 and i capped off the wastegate nipple and ran the BOV straight to the intake manifold. Went for a drive and still slow boost up to about 12psi. No BOV sound at all still. Would a bad BOV cause the turbo not to spool until high rpm?

 

[oldman]

My vac is 19 and i capped off the wastegate nipple and ran the BOV straight to the intake manifold. Went for a drive and still slow boost up to about 12psi. No BOV sound at all still. Would a bad BOV cause the turbo not to spool until high rpm?

1. Check for exhaust leaks before turbo.

2. Make sure the flapper is sealed.

3. How much pressure did the system hold and for how long during the leak test?

4. Check for turbo shaft play.

5. Do not use the BOV line for boost crontrol.

6. 2G stock BOV?

 

[95EclipseGST]

Its a blitz bov. I just hooked up a vac to the top of the BOV and it just held its pressure even when i screwed and unscrewed the adjuster all the way in and out. I dunno... No turbo shaft play. I had it holding 12 psi and sprayed everything with soapy water. No exhaust leaks before turbo. brand new manifold gaskets and everything is sealed nicely. I have brand new heads and had a valve job done and leak tested also. I am willing to pay a wiseman to come and fix this POS. I already tried the dealership. Anyone in the New orleans 150 mile radius?

 

[oldman]

Go for a test run without anything hooked up to the wastegate, watch the boost gauge and let off if boost shoots up past 12psi. Report back the result.

 

[95EclipseGST]

Do i cap off the wastegate nipple? Then run the BOV back to the intake with no T off's right?

 

[oldman]

Do i cap off the wastegate nipple? Then run the BOV back to the intake with no T off's right?

You don't have to cap it off, just leave it open.

I'm very serious about not using the BOV line for your MBC, along with many other possible side effects, your BOV will open under boost.

BTW Is your BOV recirculated?

 

[95EclipseGST]

My BOV line IS recirculated. Okay where do i make the MBC line from? Drill the dejon uicp and put some kind of nipple on there? I was just going by what the Joe P Instructions said. I also lubed the wastegate rod so the flapper moves a little better and still nothing. I will try this tommorrow with the wastegate disconnected. Thanks for the help. I am disgusted with my car. I worked on it all day and got nowhere. Thanks for your direction, i really appreciate it. I am at the point of psycho over this POS eclipse.

 

[oldman]

No problem. As for where to source for your MBC, drill and tap your J-pipe with a 1/8 npt to 1/8" fitting, or take it to an exhaust shop and have them weld on a fitting, in the meantime, move the source to the "p" port on the throttle body temporarily. I understand there are many instructions and older tech articles out there suggesting using the BOV line but that was the old way of doing things, many side effects have since been discovered proving BOV line is actually the worst and the last place you want to reference for your MBC. Good luck.

 

[romeen]

Here are some tips for installing a nipple on your j-pipe.

http://www.dsmtuners.com/forums/showthread.php?t=255444

 

[95EclipseGST]

ok, i disconnected the wastegate completely and put the BOV running to the intake. MBC is completely gone. So i go for a test run, and same slow boost but when it hits 4500rpm the boost climbs to 15 psi and it was time to shift. Still , no BOV sound maybe barely audible but really nothing. Where do i go from here? Thanks

 

[oldman]

Where do i go from here? Thanks

Repeat boost leak test and don't stop this time (now that you're trying to boost more than 12psi) until your boost gauge registers 20psi and allow no less than 30 second before it bleeds down to 0 after you stop pumping. Also, you didn't answer my question #2 above, make sure the flapper is sealed.

 

[95EclipseGST]

About making sure the flapper is sealed... I got under the car last night and moved the wastegate arm back and forth with vice grips. It is under high spring tension it seems but it does move back and forth. Is this what you are referring to?

 

[oldman]

About making sure the flapper is sealed... I got under the car last night and moved the wastegate arm back and forth with vice grips. It is under high spring tension it seems but it does move back and forth. Is this what you are referring to?

If you can move the actuator arm towards the passinger side, the flapper isn't sealed. Remove the cotter pin and pop the arm off the flapper lever then compare the flapper lever (all the way to the passinger side) to the position of the arm. If there is play, that means the actuator is old and tired therefore does not retract all the way in order to pull the flapper shut tightly.

Also, I saw in my email that you had tried to send me PM twice while my inbox was full, if it's not relating to what has been talked about here, the inbox is now cleared.

 

[95EclipseGST]

I cant move it toward the passenger side at all. I can pull it back under spring load towrd drivers side then it rests back to passenger side.

Should it take two hands on vice grips to move it back toward drivers side? It does snap back to passenger side though.

 

[oldman]

Then you should be fine, focus on the leak test.

 

[95EclipseGST]

Alright, im going to do a leak test on the UICP and the turbo inlet and see what i come up with.

 

[oldman]

Alright, im going to do a leak test on the UICP and the turbo inlet and see what i come up with.

Something I posted in the past that may help you.

1. Disable your mbc.

2. Turn your motor to 30* ATDC to avoid valve overlap.

3. Start your test at the TB elbow and focus on area behind the TB first.

4. Spray soapy water at TB gasket, BISS, TB shaft on both sides, IM gasket, injector insulators, brake booster, afpr and all vacuum lines/connections.

5. Open your oil cap and listen for leaks. (PCV, valve seals/guide, rings)

5. Listen to your tailpipe for leaks. (EGR, valve overlap, jumped timing, bent/unseated valves)

6. Once all leaks are fixed, move the tester back to the turbo inlet.

7. Spray down the compressor cover (known leak), BOV return/flange (DO NOT TAP YOUR BOV LINE FOR YOUR MBC!!!), IC end tank/fins and all connections. Re- test.

8. Note that you will leak air into the crankcase through the turbo seal but do not panic, this is normal during a static pressure test as long as there are no shaft play.

The desired test result from the begining of the LICP (bypassing turbo) is around 20psi (on boost gauge) with the compressor set at 30psi, while taking no less than 30 seconds to bleed down to 0.

As a reference, my last test on my 500 mile new engine, I was able to pressurize the system to 25psi, bled down to about 16psi (my 1G bov) in about 30seconds, then took about 3 mins to 6psi and just kinda lingered there for a while. It's not easy to do but the point is it's possible. My next goal is 30psi After motor break in and Dodge modding my BOV. A boost leak test is one of most pita but important regular maintenace task, the key is patience and endurance, have fun.

 

[95EclipseGST]

To make sure i do this right. I will take out my spark plugs and rotate the crank until the cam marks line up, then reinstall them and do the leak test from the UICP? Making sure that piston # 1 is at its highest point?

 

[oldman]

To make sure i do this right. I will take out my spark plugs and rotate the crank until the cam marks line up, then reinstall them and do the leak test from the UICP? Making sure that piston # 1 is at its highest point?

No need to pull the plugs, put the engine at TDC then rotate the crank 30* CW (1 o'clock). If you leave the engine at TDC, you will for sure have valve overlap where both intake and exhaust valves are open at the same time resulting in pressure leaking right out of the exhaust.