BoostedBalls Posted January 27, 2008 Share Posted January 27, 2008 I just bought a 1991 Turbo Legacy:clap: that is in really good condition at 158k except for this boosting issue. When I give it 1/2 throttle or more, it seems to come on really strong then fades for a moment and then pulls hard again, over and over. It feels like the wastegate is opening and closing. 2/3 throttle and WOT have about the same feel. It's funny, even with this issue it's still quicker than my N/A Legacy! I haven't installed a boost gauge yet to see what is actually happening so I'll do that in the next couple of days. I'll also replace the plugs, wires, air and fuel filters. I guess some people replace the wastegate solenoid with a GM part for a similar issue??? It may come to that; I can also wire up an LED real quick into the cab to let me know when the solenoid is powered. anyone care to place bets on the cause? Link to comment Share on other sites More sharing options...
ericem Posted January 27, 2008 Share Posted January 27, 2008 maybe the solenoid is worn? Or there is a connection issue? maybe its sticking! Maybe dump throttle body cleaning through the intake?? Maybe vacuum leak! Many possibilities. Link to comment Share on other sites More sharing options...
BoostedBalls Posted January 27, 2008 Author Share Posted January 27, 2008 yeah, good thought. Maybe I'll suck some seafoam through it at idle. I think this car has been babied and it probably has all kinds of carbon buildup inside anyway. Time for water injection Link to comment Share on other sites More sharing options...
98obster Posted January 27, 2008 Share Posted January 27, 2008 replace PCV valve Link to comment Share on other sites More sharing options...
EVOthis Posted January 27, 2008 Share Posted January 27, 2008 boost controller? just a thought.... Link to comment Share on other sites More sharing options...
Skip Posted January 27, 2008 Share Posted January 27, 2008 as a test by pass the WDS (Wastegate Duty Solenoid) with a small piece of tubing or run a rubber line directly to the waste gate. The waste gate will still function as it should and you will know where the problem lies. My 91 SS is my fave-0-rite Sube. Link to comment Share on other sites More sharing options...
ericem Posted January 27, 2008 Share Posted January 27, 2008 I am looking for a 91 SS particulary in pearl white. I really like the 91 front end compared to the 92-94. Link to comment Share on other sites More sharing options...
Skip Posted January 27, 2008 Share Posted January 27, 2008 Mine is Ruby metalic, and I agree Link to comment Share on other sites More sharing options...
ericem Posted January 27, 2008 Share Posted January 27, 2008 That colour looks hot. I would prefer some gold rims. Something like this http://s66.photobucket.com/albums/h280/turbolegacyjake/?start=60 Look through his photo's his BBS wheels also look pretty hot! Link to comment Share on other sites More sharing options...
BoostedBalls Posted January 28, 2008 Author Share Posted January 28, 2008 UPDATE- Ok, I found one of the 3/8" or so hoses that connects to the turbo inlet to be not hooked up right. I know it was leaking and probably really bad when the turbo was at full song. I took the waste gate solenoid out anyway and connected the two larger lines together and left the small line open. Then I hooked up a boost gauge. Then I drove the car. Just as boost would start to come on, the ignition would cut out??? Weird, the engine actually stalled out while I was loading the torque converter to see if I could show boost in gear with my foot on the brake. So I tested the solenoid and it was responsive and sealed tight and seemed very good to me. I shot some carb cleaner in it and blew it out anyway. It was clean inside. I reinstalled it and went for a test drive. The boost would come on and stay around 9psi but the power was still eratic. It didn't seem as bad though. The boost didn't seem to fluctuate in time with the surging. I'm gunna replace the PCV valve like mentioned earlier and I'll scout around for some more vacuum leaks. in addition to the tune-up parts Link to comment Share on other sites More sharing options...
Skip Posted January 28, 2008 Share Posted January 28, 2008 Just as boost would start to come on, the ignition would cut out??? BB, I know you know your stuff, but how do you know it was the ignition? If it was under fueled at this time (fuel delivery problem) would it not act the same? We do have an over boost cut off like the older turbos. Vrg3 has a by pass circuit. You might want to try asking over on Leg Central http://bbs.legacycentral.org/ Some really good techs over there. Link to comment Share on other sites More sharing options...
BoostedBalls Posted January 28, 2008 Author Share Posted January 28, 2008 I don't really know that it was ignition but I believe it was because it was instantanious. It didn't feel like a sudden leaning or over rich condition unless it was really sudden, like the injectors lost their ground. That's possible. Either way, it's working again once I plugged the solenoid back in. Maybe the ecu is cutting the injectors or ignition trigger when it commands the solenoid to open and it doesn't get the feedback? I know it wasn't really overboosting though, I was watching the gauge. I may have to revisit this when I setup a home-built boost controller. That will be after the intercooler and water/alky injection. thanks guys! BB, I know you know your stuff, but how do you knowit was the ignition? If it was under fueled at this time (fuel delivery problem) would it not act the same? We do have an over boost cut off like the older turbos. Vrg3 has a by pass circuit. You might want to try asking over on Leg Central http://bbs.legacycentral.org/ Some really good techs over there. Link to comment Share on other sites More sharing options...
Durania Posted January 28, 2008 Share Posted January 28, 2008 Ericem, I seen a red Legacy exactly like yours last year at dollywood. I posted a thing in Meet-Greet thinking it was a board members but I had no luck. Link to comment Share on other sites More sharing options...
ericem Posted January 28, 2008 Share Posted January 28, 2008 I saved it to my favourites. I remember getting it from a member of LegacyCentral. Link to comment Share on other sites More sharing options...
Virrdog Posted January 28, 2008 Share Posted January 28, 2008 Just another possibility. If the knock sensor is going crazy then the ECU will pull timing. This kills the power quite effectively. There are seperate periods where the car will pull timing but keep full boost... then pull timing and boost... then all of the above plus the CEL. Link to comment Share on other sites More sharing options...
mcbrat Posted January 28, 2008 Share Posted January 28, 2008 I don't really know that it was ignition but I believe it was because it was instantanious. It didn't feel like a sudden leaning or over rich condition unless it was really sudden, like the injectors lost their ground. That's possible. Either way, it's working again once I plugged the solenoid back in. Maybe the ecu is cutting the injectors or ignition trigger when it commands the solenoid to open and it doesn't get the feedback? I know it wasn't really overboosting though, I was watching the gauge. I may have to revisit this when I setup a home-built boost controller. That will be after the intercooler and water/alky injection. thanks guys! something else to try... I had a jerkiness issue just like that, and it was my O2 sensor.... unplug it, and see if it helps... my cat was getting pretty plugged as well, but the bad jerkiness went away... I still have a little bit of jerkiness, but I haven't replaced the CAT yet, plus I will be putting in a Walbro fuel pump... (I'm running a ej22t ecu in my outback.....) Link to comment Share on other sites More sharing options...
BoostedBalls Posted January 29, 2008 Author Share Posted January 29, 2008 something else to try... I had a jerkiness issue just like that, and it was my O2 sensor.... unplug it, and see if it helps... my cat was getting pretty plugged as well, but the bad jerkiness went away... I still have a little bit of jerkiness, but I haven't replaced the CAT yet, plus I will be putting in a Walbro fuel pump... (I'm running a ej22t ecu in my outback.....) Doesn't the ecm stop sampling the O2 during WOT? I wonder if the cats are clogged up... I have a stainless downpipe, I may be installing that ahead of schedule. It's setup for a Garrett so I would also have to upgrade the header at the same time. Maybe I'll just cut the downpipe and modify it for a v-band clamp so I can swap over to the garrett a bit easier. Link to comment Share on other sites More sharing options...
BoostedBalls Posted February 2, 2008 Author Share Posted February 2, 2008 Wow, I just priced the o2 sensores at Autozone. $114 for the front and $99 for the rear! That sucks! I assume the front one fails more often? Should I just replace both? dang, that's expensive! Link to comment Share on other sites More sharing options...
Skip Posted February 2, 2008 Share Posted February 2, 2008 1991 turbo legacy OBD I two (2) 02 sensors?? I didn't think so. My FSM only shows one (1) I use a generic Bosch less than 20 USD. Note: It will NOT have the heater built like the OEM model but I have seen no CEL or other indication that it is problematic. Link to comment Share on other sites More sharing options...
BoostedBalls Posted February 2, 2008 Author Share Posted February 2, 2008 1991 turbo legacy OBD I two (2) 02 sensors?? I didn't think so. My FSM only shows one (1) I use a generic Bosch less than 20 USD. Note: It will NOT have the heater built like the OEM model but I have seen no CEL or other indication that it is problematic. That's wonderful news. I thought the 91 only had one O2 as well, but I never crawled under the car to find out. It's been too wet and cold here! The j*ck*ss at autozone probably looked up an 01 legacy or some crazy thing like that. Link to comment Share on other sites More sharing options...
BoostedBalls Posted February 8, 2008 Author Share Posted February 8, 2008 Well, I disconnected the O2 sensor and I didn't notice a difference in performance. The erratic excelleration is still there. It's weird though, sometimes it makes crazy power real smooth; then later it will be erratic again. I'm gunna check out the knock sensor. I have a spare from a non-turbo model that I can test in there. I'm getting a CEL, with the O2 sonsor disconnected. Link to comment Share on other sites More sharing options...
BoostedBalls Posted February 8, 2008 Author Share Posted February 8, 2008 OK, the problem continues with the O2 sensor disconnected. The problem continues with the knock sensor disconnected. The PCV was replaced with a OEM subaru part. I can hear the turbo whistling from the front of the car when I'm under boost but I don't know how normal that is for the ej22t. The intake is all stock except for K&N filter. I'm thinking that I must have a leak somewhere between the MAF and the throttlebody. any ideas? Link to comment Share on other sites More sharing options...
ericem Posted February 9, 2008 Share Posted February 9, 2008 I am thinking a vacuum leak somewhere. I have heard of a special way to find the vacuum leak involving starter fluid? Link to comment Share on other sites More sharing options...
carfreak85 Posted February 11, 2008 Share Posted February 11, 2008 I can hear the turbo whistling from the front of the car when I'm under boost but I don't know how normal that is for the ej22t. The intake is all stock except for K&N filter. I'm thinking that I must have a leak somewhere between the MAF and the throttlebody. any ideas? When I installed the temporary OEM downpipe on my wagon a few years ago, the intake was really loud. The cat was fully plugged, but I don't recall clearly if there was any turbo noise. Might find a take-off OEM WRX downpipe off NASIOC or Craig's List and toss it on. Heck, find a WRX owner who will let you borrow theirs and do it all for free! Link to comment Share on other sites More sharing options...
BoostedBalls Posted February 12, 2008 Author Share Posted February 12, 2008 Yup, after checking the plugs (NGK BKR6E) and finding them at .045", I decided to put them at .030". They were kinda crusty, so I'll bet the cat is clogged. I'll pull it off and check. Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now