"new" car, unfamiliar turbo system, questions..

[Russnut]

I've owned a few Subies in the past. Always easy to work on. Then I went to a VW TDI. Also easy. Now coming back to Subaru with a 92 Legacy SS.

When I test drove this car, it ran just fine. A little hesitation, but pulled pretty good. After having it 2 days now, it's pretty jerky and doesn't want to accelerate much. Also, the whole idle issue.

From what I've been reading, the idle issue is most likely the IAC. Clean it, or get one from the junk yard.

Next, the hesitation sounds like a the factory boost solenoid is toasted in which case I either need to find one or do a manual boost controller. Are there any places that sell these locally? I'm in Utah.

The car seems to run fine under light throttle, but then it totally jerks and won't go anywhere with much more throttle. Where are other common boost leaks?

I've replaced the fuel filter, spark plugs, and air filter with a k&n. I sold my other car, so this needs to run better than it is.

[subydaddy]

Seems like every answer I've posted today has been about spark plugs, lol. But what spark plugs did you put in? What ones did you take out? I've discovered my car to be very picky with spark plugs.

Do you have a boost gauge? If not that'd be first on my list. I don't know of any common boost leaks but I have had my boost line come off my wastegate (aftermarket lines and turbo) which of course lead to no boost controll. Do a little looking over coolant, boost, and pcv lines on this forum, repair manuals and what have you. It makes it a lot easier to diagnose problems if you know what line you're looking at (happened to me this week with a coolant leak)

But try cleaning the maf along with the IAC.

I grab a flashlight and start looking and feeling around the engine bay when I'm around a new car. See if anything is broken, lose, or missing. Taking out the intake, washer fluid bottle, and battery help to make room.

Might be a leak post turbo as well. Maybe a crack in the pipe/hose??? Thus the reason it runs fine with light throttle (out of boost)

[Russnut]

Picked up a Grimmspeed MBC today. Installed it. It's in correctly. I know I can leave the old boost controller alone, but what about the other 2 hoses? Should there be something connected still? Yes I got a gauge too. It's going in when it's light out.

http://www.grimmspeed.com/catalog/produ ... cts_id=165

[subydaddy]

The lines that were connected to the turbo can be taken off or plugged. (I'd recommend plugging, I'm not sure if they'd still be sucking in unfiltered air plus you can keep track of them if you ever decide to go back to stock boost control)

Leave the other two lines from the intake and manifold alone.

[Legacy777]

What other two lines are you referring to? There should only be one extra line, which is the vent line, coming from the stock boost control solenoid. This goes to the resonator box and can be plugged at the resonator box.

Everything else should be the same, you take the line from the compressor side of the turbo hook it up to the MBC, and then output from the MBC you connect it to the wastegate solenoid actuator.

[cj91legss]

also, check your fuel pump, it could be going out.

[LookAsubie]

If none of these things people suggested took care of it, it could also be your knock sensor. My car used to hesitate and bog and run like poop and it was a bad knock sensor. Cost me like $52 or so from NAPA.

Good luck sir hope you get her figured out