Need help diagnosing a problem… (semi long)
I was driving the girlfriends fd home last night (7 Girl) and decided to pull into a stop to get some gas. As I pull in I lose all boost and the engine starts to shutter a bit and then slows to 32 mph and dies. I turn the ignition to off and click it back over and it starts again. I shift it back over into drive (her fd is an automatic) and give it some gas to pull into a parking spot.. but the car barely moves. Won’t rev over 2200 and the boost gauge won’t read over 0. I was able though to get it to 22 mph and drive into the space and park it.
I pop the hood to look for any type of boost leak and can’t find any. Check hose connections, etc, everything turns out ok. I do though notice that the Y pipe is broken off from one of the bolts (the two bolts on the top that hold it down) allowing it to shake and move freely. So I move it around and push it back down into place and have someone rev the engine for me to see if that was the issue. It peaked at 7 lbs with me holding the pipe down. I lifted the pipe back up like it was and it peaked at 4 lbs. So I call the girlfriend and we decided to give it a shot and try driving it home.
Here’s where it gets a bit weird.
I push the pipe down as hard as I can and hop into the car and put it into drive. The car gives me like 2 lbs and I’m able to get it up to 22 mph, then it shutters and goes to 32, then slowly rises to 40. As I enter the merge lane I accidently hit the Hold button (pedal floored since it was barely moving) and boom. 7 lbs boost and full response. Car just darts up to 60 then 80 and doesn’t seem to have any more issues. Problem though is I’m in hold and can’t leave 3rd gear. So I take hold off the car bogs, boost drops to the negatives and it begins slowing down even though I have it floored. Put it back on hold, boost rises again and it drives normally.
But this is where I’m completely thrown for a loop.
About 50 miles later and still in hold I get the idea to lay into it a bit and when I reach 5 lbs boost take off hold and see what happens (sounds like a stupid idea, I know, but I was really tired and wasn’t thinking right). So I lay into it and at 5 lbs boost I take hold off.. and I feel it shift into 4th and continue to hold boost and accelerate as it normally would. I take my foot off the gas a little bit and.. BOOM. The whole back of the car shutters and shakes almost as if I hit a speed bump. Then.. it’s fine. No more boost issues. Nothing. Changes gears, held boost, almost as if nothing had happened.
A buddy suggested maybe I had blown out the cat (air pump was not originally hooked up properly so the cat was bad to begin with) but that wouldn’t explain the issue with the Y pipe.
Anyone have any ideas? We drove the car this morning for like 20 minutes and it acted fine. No issues.
I pop the hood to look for any type of boost leak and can’t find any. Check hose connections, etc, everything turns out ok. I do though notice that the Y pipe is broken off from one of the bolts (the two bolts on the top that hold it down) allowing it to shake and move freely. So I move it around and push it back down into place and have someone rev the engine for me to see if that was the issue. It peaked at 7 lbs with me holding the pipe down. I lifted the pipe back up like it was and it peaked at 4 lbs. So I call the girlfriend and we decided to give it a shot and try driving it home.
Here’s where it gets a bit weird.
I push the pipe down as hard as I can and hop into the car and put it into drive. The car gives me like 2 lbs and I’m able to get it up to 22 mph, then it shutters and goes to 32, then slowly rises to 40. As I enter the merge lane I accidently hit the Hold button (pedal floored since it was barely moving) and boom. 7 lbs boost and full response. Car just darts up to 60 then 80 and doesn’t seem to have any more issues. Problem though is I’m in hold and can’t leave 3rd gear. So I take hold off the car bogs, boost drops to the negatives and it begins slowing down even though I have it floored. Put it back on hold, boost rises again and it drives normally.
But this is where I’m completely thrown for a loop.
About 50 miles later and still in hold I get the idea to lay into it a bit and when I reach 5 lbs boost take off hold and see what happens (sounds like a stupid idea, I know, but I was really tired and wasn’t thinking right). So I lay into it and at 5 lbs boost I take hold off.. and I feel it shift into 4th and continue to hold boost and accelerate as it normally would. I take my foot off the gas a little bit and.. BOOM. The whole back of the car shutters and shakes almost as if I hit a speed bump. Then.. it’s fine. No more boost issues. Nothing. Changes gears, held boost, almost as if nothing had happened.
A buddy suggested maybe I had blown out the cat (air pump was not originally hooked up properly so the cat was bad to begin with) but that wouldn’t explain the issue with the Y pipe.
Anyone have any ideas? We drove the car this morning for like 20 minutes and it acted fine. No issues.
I had problems with my plastic cross over pipe cracking in the middle at the flange where the bolts hold it down. The crack occurred around the flange resulting in significant compression loss. You could hear the air escaping. The crack was difficult to see. I had to pry the flange away from the pipe. A bought a replacement plastic pipe and within 18 months it did the same thing. Finally I installed the aluminum efini Y-pipe which doesn't bolt in the middle. Never had a problem since. Not sure why it cracked. Maybe excessive engine vibration, or, an overly delicate part?? I don't hear many FD owners complain about their cross over pipes.
um, start with fixing the broken crossover pipe. i can't believe you're driving around with a broken one to begin with... who needs air filtration. 
as for blowing out the cat, not likely in your case.
perhaps you should take it to a qualified mechanic? i suggest a rotary specialist b4 you get any worse problems like a blown engine, tranny or diff. check the regional forums for one around you.

as for blowing out the cat, not likely in your case.
perhaps you should take it to a qualified mechanic? i suggest a rotary specialist b4 you get any worse problems like a blown engine, tranny or diff. check the regional forums for one around you.
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