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So when I purchased my car it had an AGP WGA off PCM boost w/ TurboXS BOV. I wanted to go all back stock so I put a used stock WGA on it, a mopar blue pate and factory cold side pipe. I also purchased a brand new vacuum harness from Modern since all of my lines were non existent.

I got the solenoids out of the hole from behind the driver headlight and hooked them up. The stock WGA is making a tinging noise around the flap using my stethoscope which I have heard of before going from an AGP back to stock. No biggie, however the car now on PCM boost makes barely any boost(1-2psi) and about 15 on vac at idle. It worked fine before on the AGP off PCM boost so I am thinking maybe a solenoid. However, gonna pop the AGP back on tomorrow on PCM and see what it does. Usually a bad WGA would over boost and that is not the case here, but I am hoping it will fix my problem.

Anybody have an idea of what could be wrong?

Thanks in advance,
Modz
 

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sounds like a bad boost leak to me. Especially after changing up so much with boost/vacuum lines. you need to boost leak test the system.
 

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This may b a long shot but worth a try and it only takes < 5 minutes.

A friend had a similar "noboost" problem on his car several years ago (2003).
He had the WGA Pressure line (black looping to green at the turbo) connected to the wrong port on the solenoid.
It's been a long time, but it may have been the Green #2 solenoid that was involved.
Basically, the black-to-green WGA pressure line was connected to the bottom port.
I switched it to the top port on the solenoid and voila, normal boost.
This was a very long time ago but see if switching the solenoid ports around on #2 Green solenoid helps.
 

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Maybe these pictures will help.
Note from the decal picture where the GREEN line (turbo pressure source) attaches to Solenoid 2.
And where the BLACK line (WGA pressure source) attaches to Solenoid 2.

 

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Im not sure what the issue is with the odd sound from the flapper.

I was just going to say when you change a wastegate need to re set your battery so the pcm re learns its duty cycles. Then do some light driving for a few miles, a few shift sequences before going wot
 

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Also, if its the AGP adjustable WG then just put the 8lb spring in it and hook the line up like factory and you should be able run it on pcm control
 

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Thanks everyone. I ended up putting the AGP back on, just on PCM boost and it runs flawless.
Glad to hear it!
I ran mine like that with Stage 1 PCM and Stage 1 injectors (2003 Stage 1's needed bigger injectors) back in mid 2003 to mid-2004 before installing Stage 3 + Toys.
It was fun and ran pretty good like that (just AGP WGA, no MBC) as long as I kept the boost from spiking more than 18.4 PSI which was just about the accuracy limit for the stock MAP sensor.
Lots of guys ran like that because it was just the beginning.
Big turbo setups were cool but the tuning was handicapped with piggy back PCM's like Greddy eManage which were the best available (if you spoke Japanese) short of a stand alone.
 

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For future troubleshooting, an easy way to verify the boost control system and wastegate actuator (WGA) is working is to temporarily disconnect the factory boost reference line that goes from the boost control solenoid to the WGA vacuum canister and run a direct vacuum line from a manifold reference point to the WGA.

That will provide boost up to the internal spring tension, which for a stock WGA should be around 4-8 psi (it will also ramp up slowly). That will show the internal diaphragm in the WGA canister is working correctly and nothing has broken. If you're still getting no boost, you can completely remove the vacuum line, leave it disconnected, then very carefully drive the car and try to get into boost. You have to be prepared to immediately get off the throttle as it should spike to max boost the spring tension in the WGA will support since there isn't any boost reference on the other side of the diaphragm to cancel it out. If it doesn't spike up there might be a mechanical problem with the flapper valve broke or not sealing.


For anyone reading this and not familiar with how the stock WGA and solenoid works, the internal spring in the WGA canister is always trying to pull the wastegate flapper valve in the turbo housing shut, which would make full boost as it forces all the exhaust gasses over the turbine wheel. To counteract that and keep the flapper valve open, boost pressure is applied to the other side of the WGA diaphragm to push against the WGA spring and keep the wastegate flapper valve open.

On stock computer controlled boost, the boost control solenoid sits between the boost pressure building in the turbo and intake tract and the WGA, then cycles open and closed (duty cycle of open-to-closed) which allows a controlled amount of boost pressure to reach the WGA to counteract the internal spring and keep the turbo producing the desired boost level.
 

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I would like to add that if your W/G pin rusts and decides to break and take a permanent vacation, letting the actuator linkage pop off, ahem, on the way to work one morning lol, it will make absolutely no boost. Fact.
 
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