Confused about the turbo lag

ericem · Post by **ericem** » Sun Feb 15, 2009 6:42 am

Hi, just wondering about this SS. I find on the highway the car is great downshifts and builds boost really nice. In the city I do not find boost consistent. I find it like after 3k might pull but then let go, then start pulling again after 4k rpm, and usually it pulls pretty steady. Is this a boost solenoid issue? I find the turbo pretty unresponsive. For a little thing I would figure at 3k it would be at full boost. No I do not have a boost guage. I also noticed alot of oil on the turbo especially on the intake hoses? When the turbo is hot smokes like mad really annoying. So what are your opinions?

Tomorrow going to do the spark plugs (ngk coppers), and clean the wires till I get some new ones. Also going to take apart the intake hoses and pcv and clean it up and make sure the clamps are nice and tight. As well as clean out the throttle body. Anyway opinions? things I should look at ? Going to be in a heated shop so ya. Starting to question the boost solenoid as I DO hear a clicking noise at idle especially when cold and it seemed to be coming from around the turbo area.

Did some reading. Doesn't sound like these turbo should sound like jets lol. Driving around normally at around 3k rpms I can hear the turbo from inside, but no engine or anything else, all I hear is that turbo. Car is 100% stock! I notice when the turbo is really hot, it is not that easy to hear. I am starting to think leak! ugh!

Bdub · Post by **Bdub** » Sun Feb 15, 2009 4:53 pm

Do you hear a ticking noise, or a clicking during spool? That is a boost solenoid issue, and it would cause the sudden spikes in boost.
I'd suggest getting a 30-0-30 boost gauge to see what you car is boosting at, and you can also get a decent read of the vacuum as the car idles.
My car was doing what you describe, and it was the solenoid. I just plumbed in a MBC rather than replacing the solenoid, and my issues went away.
When I first got my car, there was also a lot of blowby in the intake hoses. I cleaned the whole intake/pcv system out really good, replaced the PCV with a genuine subaru one, and it really hasn't been that bad ever since. Minor amount of blowby is common, there isn't any way to prevent it 100%. I also ran Seafoam through the PCV system, and I noticed a huge difference afterwards.

Also, if you turbo is smoking after you run the car, take the chimney off and give it a thorough check for any leaks. If you see an excess amount of crud or old oil around the uppipe or downpipe, you most likely have a leak somewhere, causing the smoke.

ericem · Post by **ericem** » Sat Feb 28, 2009 4:18 am

Just bumping the thread. I am not really interested in putting in a MBC as I am sure the fuel economy won't be nearly as good. It is still there the issue. Alot of times I will hit the gas and it just gets stuck at 3k rpm's and i hear the turbo spooling. To clarify the only time I clear a tick from the boost solenoid is when the engine is not completely warmed up in the engine bay and if I tap the throttle at the throttle body i hear it click. Once the engine bay warms up not even a click.

Is there a way of cleaning the solenoid? Is it possible the vacuum actuator is actually the issue?

Saskatoon Subaru · Post by **Saskatoon Subaru** » Sat Feb 28, 2009 5:48 am

you can buy a MBC for cheaper than a new boost control solenoid and you can set the boost controller to stock boost levels if you want.

skid542 · Post by **skid542** » Sat Feb 28, 2009 6:59 am

Before you go and start replacing components that may/or may not be bad - you really do need a boost gauge.

Diagnosing a turbo engine problem without knowing what the turbo is really doing just isn't going to work well. You can pick up a decent Autometer for a reasonable price. It's not the best but they do a good job on the average.

You pretty much have to have a boost gauge if you want to move to a MBC at some point anyways.

I don't mean to sound like a broken record, but without knowing what the turbo is you can't really say the issue you are seeing is even related to the turbo - it could still be plenty of other things causing a stall at 3k.

Saskatoon Subaru · Post by **Saskatoon Subaru** » Sat Feb 28, 2009 3:15 pm

skid542 wrote:Before you go and start replacing components that may/or may not be bad - you really do need a boost gauge.

Diagnosing a turbo engine problem without knowing what the turbo is really doing just isn't going to work well. You can pick up a decent Autometer for a reasonable price. It's not the best but they do a good job on the average.

You pretty much have to have a boost gauge if you want to move to a MBC at some point anyways.

I don't mean to sound like a broken record, but without knowing what the turbo is you can't really say the issue you are seeing is even related to the turbo - it could still be plenty of other things causing a stall at 3k.

I 2nd that

ericem · Post by **ericem** » Sat Feb 28, 2009 5:03 pm

Well. I have a funny feeling it is the wastegate actuator. Going to take it out and clean it up. Replace the spring to if I can find the right one. If that does not work ill get the boost gauge.

ericem · Post by **ericem** » Sun Mar 01, 2009 3:28 am

It is perfectly fine. Was to late to get a gauge. Tomorrow ill look into one.

ericem · Post by **ericem** » Sun Mar 01, 2009 4:35 am

Ok found a gauge lol. Ran it through the window and watched it while my dad was driving. Actually does hit 8.7 psi when you floor it and holds it pretty steady. I guess staying in the vacuum side is best for fuel economy. Think it is more worth it to spend the money on a intercooler? or a stage 1 chip which will up boost to 13psi?? Is the air just very hot going into the intake??

555BCTurbo · Post by **555BCTurbo** » Sun Mar 01, 2009 6:58 am

Intercooler is a must before any sort of 13 psi stuff happens

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Confused about the turbo lag

Confused about the turbo lag