sluggish turbo wagon. help!

[PILOTBULLMT]

I have a 94 legacy turbo wagon that is acting like it is in limp mode. It started losing power a few months ago and little by little it became more sluggish. I just figured it was a worn turbo, so I replaced the stock vf11 with a td04 and intercooler. Nothing changed, still sluggish, poor economy, etc.

No check engine light, no codes stored, but definitely smells like it is running rich. Any thoughts? All help appreciated!

[monkeyposeur]

I had a similar issue with my SS a while back. I replaced all the vacuum lines, injectors, etc. I chased the issue for months and months and it was maddening.

 

It ended up being a bad MAF which didn't throw any trouble codes. You can try cleaning yours with a $6 can of MAF cleaner and see if that helps but in my case I had to replace it with a new one. If you replace it with a junkyard one make sure it is the MAF with the aluminum housing which was only found on some first gen legacies with a manual transmission. I also tried this and the MAF worked OK for about a year and then it crapped out on me.

 

Your fuel pump could also be going bad. Mine was going bad at the same time the MAF was dying.

 

So if I were you I would start by cleaning the MAF and checking for vacuum/boost leaks. Also check your spark plugs for proper gap and if one is loose.

[bcmaxx]

chasing a similar issue, days of doggy sluggishness, mixed with days of rip snorting peppyness. was brutal yesterday, this morning it wanted to bark all fours. just ordered an aem digital fuel pressure gauge, and installing an oem new maf tonight. it has to be one of the two things

[PILOTBULLMT]

Thank you for the responses. Back when I first got the car it had some sluggish behavior issues interspersed with days of great performance as bcmaxx mentioned and I sprayed MAF sensor cleaner in and it was 100% a different car afterwards, but then it went back to sluggish a couple months later, so MAF cleaning again and back to normal. I just cleaned the

MAF again and noticed the hotwires have a brownish buildup on them which I very carefully cleaned off with MAF cleaner and a Q-tip. I suspected a failing MAF sensor so I will look into that further, I have an extra but I'm not sure that it is any good.

I also noticed my 11 psi ignition cut is not working as I saw 15 psi by accident the other day. It has always worked before. Could that be related somehow?

[GTEASER]

You are resetting the ECU after you clean the MAF, right?

[PILOTBULLMT]

I ran a code check, but did not reset it. Which method would you recommend? I see about 5 different ways to do it.

[GTEASER]

Reasons to reset the ECU. Preferred method being disconnecting the neg battery cable.

 

1) cleaned MAF

2) hit fuel cut

3) changed O2 sensor

4) changed injector(s)

5) changed MAP sensor

6) changed BCS

7) changed turbo

 

Do you have a wideband and boost gauge?

[PILOTBULLMT]

I have a boost gauge, but nothing other than that since I'm not looking for much more than a stock performing car.

Is there any special procedure after disconnecting the negative cable, like wait 30 minutes? How about after reconnecting?

[GTEASER]

Disconnect negative, wait 10 seconds, step on brake pedal for a few seconds, connect battery. Once you restart the car it will take a few minutes of driving for the ECU to relearn so it may seem a little weird, but it will smooth out by the next day.

[PILOTBULLMT]

Ok, thank you. I will give that a try and see what happens before digging into the MAF.

[bcmaxx]

just another thing to think about IAC? also subaru procedure is to touch positive and negative together after the 5 min. I think turbo iac have a one way valve. I'm ruling out my non turbo iac tonight with nan inline check valve

[PILOTBULLMT]

I reset the ECU, and have driven a few separate times and the acceleration has improved quite a bit. Ease the accelerator on, build boost, and it really moves, but stomp on it to pass someone and there is quite a hesitation, but I wonder if it might be the bigger turbo. I need to do the pass test to see how it does in the mountains.

[PILOTBULLMT]

I may try the other MAF sensor with another reset just to see if there is a difference, since it still seems to lack the zip it had a few months ago.

[bcmaxx]

The td04 should spool really good. I cant see that being your problem. We see a lot of coolant temp sensors going bad causing grossly rich problems. Fuel filters been ruled out too?

[PILOTBULLMT]

Thank you bcmaxx. I checked this morning and my td04 has the potential to make gobs of boost, even before 3000 rpm, so it's definitely not the bigger turbo. It just seems like the faster the boost comes up = worse performance, slower boost = very fast car. And I don't mean throwing an instant 15 psi at it, its more like 9 - 11 psi. And under hard acceleration the car pulls hard to 4 - 6 psi, then it doesn't matter how much boost you throw at it it takes a while to catch up to the demand.

I'm going to change the fuel filter, and it's probably time the coolant sensor was changed too since that is often a rich-running culprit. The engine has 140k and it is probably the original sensor. Could the MAP sensor have anything to do with it?

[monkeyposeur]

I've never heard of a map sensor going bad on turbo leggys. I asked the same question on bbs when I was having hesitation issues like yours. A new one is outrageously expensive. My money is on the MAF being bad. Next bet is the fuel pump. A reman MAF on ebay or Amazon is about $160.

 

When my second MAF went out and I finally got a new one the difference was amazing. Also the car would go into POWER mode when I stomped on it whereas before POWER mode would only come on when I hit my custom switch. If you haven't already done the POWER mode mod I highly suggest it. Shift maps are much more aggressive and the car is a lot more fun. Almost as fun as a 5mt which I would swap in but I gave the SS To my wife and she likes the 4eat. Here is how I did the mod if you're interested: http://legacygt.com/forums/showthread.php/rocker-switch-question-198670.html

[bcmaxx]

yes if you havent done the power mode on the auto do it! I firmly believe it is also easier on the tranny, and will prolong its life

[PILOTBULLMT]

The reason I asked about the MAP is related to difficulties I'm having reigning in the boost pressure on my turbo. Even with a manual controller fully open I can easily spike to 15 PSI when I'm on the highway or climbing a steep hill. In the past ignition cut would kick in at 11, and now ignition cut seems to be non-existent and I thought the MAP controlled that.

I plan to do the power mode conversion soon. I'm actually designing a 4-way switch that will incorporate power (sport) mode. The selection options will be: 2wd regular, 2wd sport, 4wd regular, and 4wd sport. Any thoughts on the AT filter kit Subaru sells that plugs inline with the AT cooler??

[PILOTBULLMT]

I swapped MAF sensors and tried that, but it really didn't change performance so I dug a bit deeper and discovered that the intake boot to the turbo has turned rock hard and had at least 7 decent sized cracks so I sealed those up and ordered a new one from Subaru($130!!) and hopefully that helps. I have a 600 mile trip on Friday, so that will be the true test to see if my problem is fixed.

[monkeyposeur]

I'm surprised you were able to find a new OEM boot. They are an obsolete part now. I tried to order one and was told there were no more left in this country. Luckily I was able to find one in Canada. Where did you find one?

 

That cracked boot would definitely be causing unmetered air into the system. I would also recommend doing a boost leak test to find any other potential leaks. This is how I did it: http://legacygt.com/forums/showthread.php/diy-boost-leak-tester-ss-199337.html

 

When my boot was cracked replacing it helped a little, but didn't solve the sluggishness completely.

 

Did you swap the MAF with another used one?

[PILOTBULLMT]

I called my local Subaru dealer and they were able to get it for me and it is $99, not $130 like I originally thought. I know there aren't many left, but I know it's not the last one. I still order parts for my 87 RX from the Subaru dealer and there seems to be a good stock of those.

The other MAF sensor was a used one too, so I wasn't very optimistic about it working.

Any thoughts on why the ignition cut isn't functioning?

Also, in the midst of this, any suggestion on how to bring the boost down? I'd like 10 or 11 max.

[PILOTBULLMT]

Well, I posted too soon... Subaru just called back and said that even though inventory showed 4 in stock, they are sold out of the intake boot. Where in Canada did you get yours?

[monkeyposeur]

Welcome to the broken turbo inlet club! They break just by looking at them. Even my brand new one cracked a PCV port when it was a couple months old. JB Quik (NOT Weld) can hold them together pretty good but just don't allow any of the repair to come loose and get sucked into the turbo, lol.

 

I wonder if your electronic boost control solenoid is malfunctioning. That's strange about your fuel cut not working properly. Was the car modded by the previous owner? I ask because it is possible to make a DIY fuel cut defender so maybe the PO installed one?

 

I asked a guy on bbslegacycentral who lived in Canada to see if he could find one for me. That was a few years ago. You could try Richmond Subaru in Vancouver. They was a rumor they still had some a few years back. bcmaxx works for Subaru in Canada, maybe he might know of a source. Or just search for Subaru dealerships and Canada and start calling them.

 

It's not too bad to fabricate one out of silicone. You can get everything you need at siliconeintakes.com: http://www.siliconeintakes.com/?osCsid=ff848867830ef9bf407265b9893165f9

 

You can buy a reducer elbow and also they sell ports: http://www.siliconeintakes.com/holset-turbocharger/-p-500.html

 

It is also possible to make one from some parts from Autozone or whatever. Here is an example of one courtesy Martimus919 on bbs as well as a vacuum diagram with the diameter of the PCV lines which will come in handy if you fabricate an elbow yourself and need to order the correct bungs.

 

As much as we love to try and help solve first gen problems on this forum all you need to know can most likely be found on bbslegacentral. It's the greatest site for first gens and there are very knowledgeable people on there eager to help.

[bcmaxx]

this goes between the intake resonator and the turbo inlet|?

 

the parts catalogue is hugely unclear on the part number. if its 46023aa110 they show 4, i ordered one in to see if it would come. if its # 46023aa020 there is no stock anywhere...

 

http://i232.photobucket.com/albums/ee110/bcmaxx/20150519_143431_zpsdz7gf0ed.jpg

[PILOTBULLMT]

I did the mods myself and experienced ignition cut a few times (11 - 12 psi) before dialing it back to stock settings and leaving it there. When I added the td04 I was surprised to see that it wasn't working. I have the boost control solenoid disconnected in lieu of a manual boost controller, but I was certain the MAP was responsible for ignition cut, and it is still connected.

I'm pretty creative so I'll just design something to take the place of the intake boot. I'd like to relocate the PCV nozzles elsewhere to reduce the oil vapor mess inside the intake and turbo.

bcmaxx - it is part #6 on that diagram