Help with Possumlink 44S

[Zane Hansen]

Here's the problem. Hopefully someone can help me out. I finally got my boost controller under control so I know that it isn't the problem. I finally got my 2002 Suabru WRX back from the shop. Has a newly rebuild 2.5l engine with forged internals. I have a GT30R turbo rotated kit with all supporting mods. Injectors, fuel pump, fuel rails, etc.. Anyway before I took it in to get built I was hitting about 17psi just fine. Now that I have gotten it back the car won't go over 15 without hitting some kind of fuel cut or something. So now I set the boost controller to hit about 14.5 and it pulls those numbers all the way to 6000rpm. I just don't understand why the car won't go over 15psi when it was set to 17psi before I had the engine rebuilt. Do I need to set some numbers different on the ecu or what? Hopefully someone can help me out here. Thanks. My goal is to hit 21psi.

[Zane Hansen]

Here is the map that I have on my pclink. Hopefully it works.

[Zane Hansen]

Here's a log that I pulled awhile back.

[Jurgen Biggelaar]

Hi Zane.

Weird.  Not sure what that could be.  It sounds either like there is something not quite right with that boost control (don't know what type you have or how it's programmed), or something mechanical.  When I say mechanical... Maybe you told your engine builder about your boost target and they have built it with lower compression in preperation, which may screw with the set up of the boost controller that worked fine on the 'higher compression' motor???

Just trying to give ideas here really.  If you are daring enough, you could pop the pipe off the wastegate and see if it goes over 15PSI, just don't stick it through the roof!    Although the Link's MAP limit is set to about 17PSI, the other thing would be to raise the limit on that to see if it is the ECU limiting or something else.

Let us know how you get on.

 

Jurgen

[Zane Hansen]

Thanks Jurgen for the answer. My tuner and I have tried pulling the pipes off the wastegate and it does the same thing. For some reason something is holding us back. When you say to change the limit on the MAP limit where do you do that? If I am correct we may have it set to 255 kpa right now and the results are still the same. Would my MAP sensor be bad or would I need to upgrade that? I bought an Omni 3 bar MAP senor but when I took off the older one the omni sensor is a bit longer than the older one. This is just confusing. Thanks again for your help.

[Cameron Moore]

Hi Zane,

How are you measuring the boost? Are you reading off the ECU or do you have a mechanical gauge?

Does the boost controller have its own MAP sensor or are you sharing the ECU(factory) MAP sensor?

The 44S is designed to use a 'GM' 3 bar map sensor, if this Omni sensor has a different scaling then there's a chance the ECU thinks it's 17psi when you only have 15psi. Is the ECU set to use a 3 bar? The factory sensor should be good for 22psi so maybe change back?

-Cameron

[Zane Hansen]

Fixed the problem. Wasnt the tune. Spark plugs were gapped way to much. Put new ngk one step colder in and it boosts fine to 21psi. Thanks guys for your help.