So I got a tune by Mario and all went great but I can't seem to boost past mid 17psi. I just got finished replacing the DV and upgraded to the Alta spring. No change. The original DV didn't have any rips. Anyone have some insight on what it might be? Mario is working with me but want to open up to ideas. I have a one piece hot charge pipe to install as well as an intercooler. Current idea is to adjust the wastegate in case that is what's not holding. Anyone else have ideas? Should I just do boost leak test?

 

Just curious, what level tune did you get and what psi are you supposed to be hitting?

 

Stage 2- should be seeing 20psi. Change the hot side tube tonight, checked cold side connections and did a vac test on the wastegate and now I'm only getting 14 psi!!! Mind boggled right now

 

do you have the SPS switch? from what I understand at stage 2, theres a low med and high boost option

 

So went for an hour or so drive after my modifications last night and boost reading remained the same. When I got home I rechecked all my hose clamps and connections and went to sleep. Drive to work this morning and it gave me an extra 1psi, still only 15psi but it was 30* colder this morning so not looking into that too much. It got me thinking that other than the tubes and clamps, I removed the vac line to the wastegate to check it. It was on there snug so didn't think much of it but now thinking maybe there is a leak in the vac line itself. Is there any special type of vac line I need or can I just get "cut to fit" stuff from autozone?

Also, is it safe to manually close the wategate while idling? I want to test that it is working properly and was thinking if I idle the engine with a vac leak tester attached to the WG and apply vacuum and watch to see if boost increases.

Edit - Yes I have the SPS switch. I max out PSI at the same number in all maps.

 

How many miles on the car? Not sure its relevant but do you have to adjust the wastegate actuator arm at all once you receive the ECU back (don think its required). Possible the ecu is still learning? Was it 93 octane gas? I know Map A ia 1.3 Bar , MAP B is 1.4, and MAP C is 1.5 but you arent seeing any difference between them all. Did you do the step colder plugs?

 

Car has 89k on it, it is not required to adjust WG after the tune, at full throttle it should be shut. The weird thing is, the boost builds quickly and well but once it hits about 13psi it just falls completely flat. Really weird. Same happened when I was hitting 17psi, accelerated great but then just fell flat at 17psi. If I go stock tune, car drives like it did before all the mods.

 

Is your boost gauge showing negative vacuum at idle with electronics on or off?

Are you are stage two with no FMIC?

 

I have a Scanguage to read my boost. At idle I'm usually reading anywhere from -1.0 to -0.5psi. And yes, no upgraded intercooler just yet, I'll have it install by this weekend. It's still cold enough out and I dont romp on it for more than an on ramp blast which only raises the IAT 40-50* max over ambient.

 

So just an informational update. Just trying troubleshoot here, went out to parking lot, popped off the vac line to the WG and went for a drive. Even with no WG I was still able to build 5psi but it did at least prove that the WG is moving when vac is applied and that there is some vac making it to the WG

Back to my earlier question though, If I hook up my vac leak detector and apply vac to the WG, the car should build boost correct? Or is the DV just going to open and dump all the boost since I'm not under load?

Also, I could check the line for leaks by hooking up the leak gauge to the vac line and see if I'm hitting at least 15in correct?

 

if you are not building the proper boost, you either have a boost leak, or a part of the turbo is not functioning correctly. but to measure the WG without load may not work properly.


chasing down a boost leak can be tough in a system, but you need to block off before the manifold and get as much as you can in the system from the compressor to the intake manifold. cap off one end then get some air pressure in the other side with a cap and spray some soapy water on the joints, or you can get a gauge and see if the system can hold 20 psi.


the DV valve could also be dirty and not be able to close all the way allowing some air to escape

 

DV valve is brand new, just installed a few days ago with an upgraded alta spring. Something happened when I was changing the tube yesterday and checking the vac on the WG. I went from 17.5psi before to barely 14psi after. Something with the hot side pipe, wastegate or vac line made it worse. Not having enough vac to close the WG can also be why I'm not getting the right boost or that the WG is not closing fully. That is where I am currently focusing.

I'm going to try and manually apply vac to the wastegate and see if I get desired boost. If that works then I will move to the vac line and see if it is giving me 15" vac required to close the WG. If that all works then it HAS to be a boost leak, in which case I'll need a boost leak tester which is pretty cheap in the interwebs and I can just plug the the end of the cold side pipe.

 

did you end up replacing the vac line?

 

Haven't replaced the vac line yet. Those tests are my plan of attack for the evening after work. Trying to be systematic and not just see what sticks or fix what's not necessary

 

was wondering if the vac line was cinked in anyway

 

Would love for that to be the issue but my luck, it isn't haha. I put the vac tester on the line and tried to get a reading last night but I couldn't pump fast enough so ruling out the kink, doesn't mean there isn't damage to the line though

 

So lots of testing and fidgeting last night. Here is how it all went down.

-Got home and hooked up my leak tester to the WG vac line, went for a drive and watched the gauge. I routed the line up to the wipers and only soft closed the hood, I was able to hang the gauge over the side view mirror. Was getting 20" vac no problem. Bad line ruled out
-Then moved the tester to the WG itself and went for a drive. Obviously with no vac line attached the WG stayed open and I had no boost, so I then pumped it up to 15" and got boost but again only 14psi. So we either have a WG issue or boost leak in the piping.
-Put the car up in the air, pulled the DP and checked the flapper on the hot side. It closed nice and smooth but unfortunately it has so much play that it doesnt seat correctly and leaves a small crescent at the top of the port open, hence why I cannot build proper boost.
I played with it a little bit and conceded to the fact I need a new turbo BUT! on my drive after putting everything together I noticed the car pulling really hard. I don't live very close to a highway so I could only hit 2nd gear at WOT but I was seeing 17 psi in 2nd! Tired, cold and dark I put the car away for the night. On my commute this morning I had some higway driving and hit 19.2 (approx max is 20)!!! Whatever I did helped immensely! Spool is way faster, it sounds much throatier and pulls really hard. I'd suspect I've had this WG issue since I purchased the car a couple months ago but never noticed since at stock boost it isn't an issue. I even put the car back to stock map and man it is a way different car than the one I purchased. I know I haven't "fixed" the issue but at least I know what it is now and can plan on a new, bigger turbo in the near future.
I have to note, when I first noticed the issue I contacted MarioKart who did my tune, the first thing he mentioned was check the WG flap. Reluctant to pull my DP I checked 10 other things first with no avail. Just want to shout him out for really knowing his stuff and helping me from 3000 miles away! He spent easily 30 mins on the phone with me last night talking about options for new as well as possible temp fixes on my current setup. Will hopefully be purchasing one of his turbos in the near future, highly recommend doing business and seeking advice from him.

 

excellent, you way be able to fix the flap, just sounds like there might be some play in the hinge

 

I was hoping that would be the case but the linkage seems to all be one time use stuff with no adjustment, except for the throw which is fine. In order to mess with anything I'd have to pull the turbo and with that much effort to just band-aid the situation I'd rather just replace and have peace of mind. It has 89k on it so its just about at the end of its useful life. Plus, since its a fix and not an upgrade, the wife isn't all that upset :-) . Sure glad I talked this car 6k down from asking price! Figure I'm going to be dropping that into it before I'm totally happy with it.