Topic: HELP! Ej20g 6psi and slow acceleration

[1ofakind]

Hey guys hope I posted in the right place, car is a 93 jdm gc8 I'm really wondering what's going on with it. I put a boost gauge in yesterday and was only hitting 6psi.. vacuum is around 15 at idle. it never builds boost in lower Rpms, I can step on it and will only get 1-2psi till I'm up higher in rpm. I re did all my vacuum lines, I do have a crappy stock bpv that the nipple broke off of so I epoxied the hose to it to run to the intake manifold... could that be my issue?

I have two codes. Code 24 and 44.

I made sure my waste gate was opening and closing but maybe its opening to soon? I don't know a lot about these cars yet but I did install the motor my self.

I also tried bypassing my bcs, I just tied them all together and that got my boost up to 7psi or so. But then I'd get a fuel cut or something right at 5000rpm WOT. So I Put my bcs back on and that fuel cut went away.

What's going on here, I don't have any leaks as far as I can tell, but maybe my bpv is garbage? Is there anything else I can check or some ways to diagnose? I've been reading for hours trying to figure it out. Could I zip tie my waste gate shut to confirm it's not opening early?

Also can I try and ej20k solenoid? The two port?

[AirbornBugeye]

https://forums.nasioc.com/forums/showthread.php?t=2125765

With OBD I Subies, the only reason that a sensor would trip a code would be the following:
1. Sensor is disconnected.
2. Sensor is not receiving power or is not grounded properly.
3. The sensor itself is shot to the point it cannot communicate with the ECU.

Code 24 would be for the Idle Air Control Valve. Is your idle funny in anyway, like does it go up and down or is it low or high?

Code 44, as you have said is for the wastegate duty solenoid.

First things first, check and make sure the connectors are plugged in.

If they are plugged in and you know how to use a multimeter and a testlight, test for power to the sensors using the testlight and test to make sure that the sensors are being properly grounded.

If everything tests out then your sensors themselves are most likely messed up beyond all recognition.

The guy never replied after that so its really the only thing there is to read on that post.


Also if the IACV is giving you issues
https://forums.nasioc.com/forums/showthread.php?t=781242

[1ofakind]

Thank you for chiming in! I think my issue is the solenoid as I took the line off to the waste gate actuator and now boosts up to 9psi then cuts hard like I hit a wall so. So I think I need a new solenoid?

[AirbornBugeye]

Here is something ive found just by quickly looking around
http://www.westernsubaruclub.com/smf/index.php?topic=24069.0

Reset ECU using dianostic connectors under the dash. After reset took the car out for a drive.
Feels so much better hitting 10 PSI in all gears

Still not hitting what people say it should be (14 psi) but I am not consistently hitting 10 pounds in every gear so I am satisfied. I think I may have gone through a bad tank of gas, or the gas went from running 94 octane from the previous owner with using octane booster to 91 octane v-power and adjusted the timing a little too intensly. Quick reset and now all is well.

Still any ideas on why I wouldnt be hitting 14 psi though? Quick MBC fix this set up?

I thought I was the only one 

For what its worth. My first gen EJ20G runs 10 PSI stock. In limp mode, I hit ~5 PSI. Coil conversion did nothing for my boost levels. Neither did fuel filter or new plugs.

I suspect I may have a vac leak that forces me into limp mode occasionally. If your car runs 9PSI in 1st and 2nd, it may have switched to limp mode after throwing a fault during the shift to 3rd.

Have you pulled the ECU codes? Is the check engine light on or did it flicker after 2nd gear?

If its going into a limp mode or fuel cut I would look for whats causing it.

[1ofakind]

Thank you, I was already reading that thread.. I think I will try a boost controller first. I still find it weird I bog with the line off the actuator. Must have a leak but I replaced a lot of lines already. Could be my intercooler y pipe or my bpv? I known my y pipe had a crack right on the coupler I thought the clamp would suffice..

[AirbornBugeye]

Did you make sure to keep your restrictor pill?

Im not to sure what you mean when you say you have the line off the actuator.


If you dont have a line attached it wont open right?

Also, diy leak tester
https://forums.nasioc.com/forums/showthread.php?t=2205161

[1ofakind]

Did you make sure to keep your restrictor pill?

Im not to sure what you mean when you say you have the line off the actuator.


If you dont have a line attached it wont open right?

Also, diy leak tester
https://forums.nasioc.com/forums/showthread.php?t=2205161

Thank you for the input I was just about to google a boost leak tester lol. So I found two potential leaks just by looking. One on my intercooler pipe and one on my turbo inlet.. fixed them both and now going to wait to put it back together till tomorrow when I get my mbc.

As for the line I disconnected, I took the one off the actuator and still et the bog and when it starts boosting to 6-8psi it will drop to 0 right away like I hit a wall. So I don't know what Else to do other than check for leaks and then install the mbc.

I have the 20g with the 3port boost solenoid, I wonder if I can plumb It like the 20k and t the line like shown in your pic..

[1ofakind]

Also I need made sure my bpv isn't plugged with epoxy. I should just get a new one...or an aftetmaket bov

[1ofakind]

I posted this in the other forum I'm on and got a good bit of info I want to share. Here is the https://forums.nasioc.com/forums/showthread.php?t=2863866

[1ofakind]

Today 10:30 PM by 1ofakind03
OK bad news. Getting frustrated now. Put in the mbc fixed what I thought were all my leaks and now I still get the hard cut right at 7-8psi. IT is a little better but still Boggs if you WOT at any rpm under 3000. I swapped my iacv and my coolant temp sensors and did not help still get the codes.. I wonder if I have s bad ground.. shouldn't I be able to boost much higher now though regardless?

What now?

[Markkenko]

The guys on NASIOC seem to have much more info on this topic than I do, but if you are still stuck I would just triple check that you dont have any vacuum leaks anywhere. If youre positive that there are no leaks, then maybe try resetting your ECU?

[1ofakind]

The guys on NASIOC seem to have much more info on this topic than I do, but if you are still stuck I would just triple check that you dont have any vacuum leaks anywhere. If youre positive that there are no leaks, then maybe try resetting your ECU?

you know what i didnt do is reset my ecu, but i did pull my battery cable to swap my coolant sensors so in theory should have reset... im going to build a boost leak tester and a friend of mine is going to look it over with me. i think im having a fueling issue. its intermittent the bog, sometimes it does it sometimes not but i can never build more then 6-8lbs of boost.

[1ofakind]

Well problem solved. I went to a reputable Subaru mechanic and we had it running in an hour. Turns out I had two dead coil packs causing me to run on two cylinders. DId a compression test and was at 120. Cleaned out the fuel injectors and also had no power to my boost solenoid so it went in limp mode causing the violent cut. All added up to be just a bad wire to the solenoid and two bad coil packs. Now I just need to turn down the boost since I get fuel cut around 16psi lol!! What a relief, so much better to have it back to normal ! Thanks all for the help hopefully this helps you guys as well. Funny thing is, I replaced all my coil packs with 02wrx ones and never would have thought to recheck them.

Codes are now clear and runs flawless!

[Markkenko]

Oh wow... Yeah, that would do it haha. I was going to recommend you swap them, but after reading you did I was surprised they were the issue. I too would have probably not looked there unless I checked my plugs.

Glad it's all sorted now though.

[1ofakind]

Glad I know my car has good compression lol, ran on two cylinders for quite a while