Alright guys, it all started when I hooked up a boost gauge last week to my FD and found out that my boost pattern is 7-4-7...when I should be at 10-8-10.

After extensive searches and having my eyes bleed from reading, I've narrowed it down quite a bit. Someone please confirm I'm on the right track here...

My mods are DP, street port, silicone hoses...stock ECU (until I fix this problem) I have 15,000 miles on motor and turbos.

Here's a list of thing I did in order to narrow this down:

1) Sprayed carb cleaner to check for vaccuum leaks with no luck. My vacuum is at steady 15-16 fully warmed up.

2) Check for leaks...and even swapped hoses off a friends healthy FD with no luck.

3) Checked for pills in the prespool and wastegate lines...found none and installed pills with no luck. Turns out I have them in the hard line. (crap)

4) Thought I had clogged cat and disconnected the DP from the cat...still same pattern. (but man it was fun)

5) Wanted to check my wastegate out, so I disconnected the bottom bleed hose and wow I got instant 10-12lbs before letting off (it'll go up forever seems like)...so I guess the wastegate wasn't "stuck open" before.

6) Hmmm...so at this point I'm thinking, maybe the wastegate solenoid is not working and it's stuck shut, not bleeding off the pressure from the actuator. So I swapped that with my friends good solenoid last night and STILL 7-4-7!!!

I'm gonna go nuts...is it the wires to the solenoid, or the ECU!!

Someone please help me out here, am I close!!

 

intercooler fittings...

 

He says he swapped hoses with a friend and I assume that is what he meant.

Along those same lines, however, did you check your intercooler to see if it is separated anywhere. The stock intercoolers have been known to separate at the crimp seams at the top and bottom.

 

Check for crossed solenoid WG/PTC electrical plugs.

 

I did suspect the intercooler...but figured I definitly didn't have a boost leak after I was able to go easily 10lbs + with the wastegate shut...

I still have the white markngs on the solenoid and harness...but just to be sure I did switch it once for kicks and still had low boost...


Does any body know how I can check to see if the actual harness to the wastegate solenoid is sending signals...?

 

If you think one of the wastegate/precontrol solenoids is bad you could temporarily switch the plugs AND the lines to the solenoids. This will let you isolate the solenoids and will point you to the bad one if that is what is actually wrong.

 

Have you verified that you gauge is accurate? You just may be looking for a problem that isn't there.

But in case have checked your BOV?

 

did you try to use a manual/ball and spring type boost controller yet? perhpas the hole on the pill you have in the wg line is too big right now.

it only cost about 5 bucks for a bleader valve and like 15 bucks for a ball/spring type so its pretty cheap to try out

 

Damon, I switched the solenoids with a good one last night and had the same pattern...came to the conclusion that it's the wires or the ECU. What do you think?

Montego, I actually used two different gauges in the last week...the one I use right now is a autometer.

Again, I was able to boost up when I had the wastegate shut... just no control. I can probably fix this with a manuel controller but don't want to "band-aid" an existing problem.

Edit: Sorry Damon...AND the wires, how do I do that??

 

Since I have a pill in the hard line...I actually did put a smaller pill (.059) in the wastegate hose...no change.

I think I'll try the manuel controller temporarily just to confirm my thoughts about the ECU signals...

Quick question...manuel controller would let me cap the wastegate actuator bleed off right?

 

Doh! missed point #5

 

^

 

Have you checked to make sure the actuators are attached?

 

If you say it works with the bleed disconnected, then it sounds like the solenoid isn't working. Easiest test for the harness:
1) Pull codes (is the wastegate solenoid code there?)
2) If not disconnect wastegate electrical connector
3) Pull codes again (makes sure the right one is connected)

Or bypass the wastegate solenoid with a needle valve.

 

I acturally have the same exact problem.. with my avc-r.. still have this issue.. just too lazy to fix it..

I was going to put my stock solenoids back on and let it control by PFC..

But I do have a question regarding to this issue.. If one of the lines say vac or wastegate lines is leaking, would it also cause this issue?? Besides the solenoids, anything else??

 

It definitely looks like wastegate control - nothing is holding it closed.

Clogged/pinched vac line to the wastegate control? The "bleed line" is just connected to the intake elbow and has no vac/pres on it. Removing it should not affect boost levels.

It sounds like you have a blockage in this line.

Have you also verified all your check valves are pointed in the right direction?

-bill

 

I wish I could pull codes...I've had a problem with my diagnostic system for a while now, but that's a different story. (it does give me a reason to think that all my problems are linked to the ECU though)

I think I'm going to check the wire from the ECU or maybe do a temporary swap...if I have no luck...than manuel controller it is.

I've checked the check valves..there in very good condition and also in the right direction...Boost pattern seems good just low.

As far as the "bleed line" from the actuator, it's actually connected to a hard line that leads to the wastegate solenoid...if it was disconnected without capping the actuator side, then you would see crazy spikes...if it was clogged then you would see 7lbs.

 

Question about the PFC...I'm gonna install one soon....do I absolutely need the solenoids?

If so, then I really need to make sure I find my problem before installation...

 

which solenoids?? I did the simplification seq. system and worked beatufully.. until something happened and 7-4-7.. or nothing above 7..

I'm going to check the wastegate line..

 

and you are seeing 7 lbs, right?

I was actually thinking of the other line - the one that sources air to the solenoid from the intake line. Have you tried removing this line and seeing if there is a problem?

-b

 

Well, we've been talking about the two solenoids right in front of the UIM near the black plastic tank. The one on the left is the prespool solenoid and the one on the right is the wastegate solenoid.

I've been speculating that my problem revolves around the wastegate solenoid because if that's shut closed then the wastegate actuator opens the wastegate prematuraly and let's you boost to max 7lbs.

Now, if you've done other mods to your turbo system, I don't know if you still use these solenoids, so you need to check I guess.

 

Hmmm... you mean one of the two vacuum hoses on the solenoid other than the one that goes to the actuator?

What would happen if I unplug it...what should I look for? I'll try anything at this point to pin point this crap...

 

You can always pull the codes like we do in the RHD countries. The FEN signal in the diagnostics connector also flashes out the codes. You need to either connect a test lamp between it and +BAT or an LED in series with a 680 Ohm resistor between the same points.

Still need to ground the TEN pin.

 

Thanks rpm_pwr!!

I never knew there was a way around it, I'll try that soon...

 

You could also T in to the various vacuum lines out of the solenoids. Just move your boost gauge's line around. Others have posted good success using this approach becuase it lets you 'see' what's happening while everything still connected.