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Discussion Starter · #1 ·
I got in my car this morning and right when the boost kicked in it started going up and down very quickly like was totally unsteady going from like 7 to 10. It was like flickering. I got scared a parked it for the day. I have a Joe P. boost controller and I have never had a problem like this before. The night before it ran perfect. I think maybe it might be a vaccum line going to the y-pipe it didnt have its clamp on it for some reason. Think maybe some air is gettin out or something causing this. Any ideas would be appreciated.
 

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Check the connection to the nipple on the ypipe as well. When mine blew off, it would overboost like crazy as well.

LW
 

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Discussion Starter · #6 ·
Now when I got home and tried driven it again at its the car not the gauge. I think its my spark plugs when I gas it seems like its missing a spark and dropping psi then rising and its runnin like total shit. It can kinda build boost but it bounces back and fourth insanely and feels like my spark plugs. So I guess all I need to do if that is the case is get new spark plugs.

Also I planned on gettin new spark plugs anyway becuase I never had them regapped to .032 when i turned up the boost.
Does anyone know whats going on.
 

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I don't think its your spark plugs.. I had some pretty extreme spark plug problems and I didnt experience boost fluctuation like you describe... It would miss like crazy, but there was always the set amount of boost going into the plenum....

Its not the car, its not the spark plugs, its nothing in the engine... it has something to do with your guage, hoses, connections... etc

Check anything and everything that connects to the y-pipe or the plenum..
 

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Discussion Starter · #8 ·
I just went for a ride letting it idle for about 10min. before and it ran pretty good. It was like 20 degrees in stl this morning and I didnt warm it up. Maybe this might cuase that but I doubt it. This is very wierd.
 

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I agree, it isn't your plugs. If you were experiencing blowout from large gaps in plugs it will cut out, or act like fuel cut at a lower rpm. With factory turbos, you should be able to run full boost 1.00 bar without blowout, but with bigger turbos it becomes a problem.
I also had major problems with a bad plug recently and it caused backfiring and heavy detonation (knock) car would buck and stumble and cough black smoke. Removed the plugs, regapped them to .032 and found one without an electrode on end of the plug.
It really sounds like a vacuum leak around the boost controller somewhere. My ypipe vacuum hose blew off and car would boost to 18psi while using an EVC IV ebc. Turned out I forgot to tighten the clamp holding it on. If yours has split or something it may cause similar problems. Can't help with manual controllers though.

Lord Warlock
 

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Discussion Starter · #10 ·
Well it spudders and kinda and bounces however it never overboost, it stays at about 14psi like I have it set. It weid like right when I turn on the car it has this problem but then after like 2 min. it fine a runs great. I also just installed a type RFL BOV. My y pipe connecter doesnt have a clamp on it and it used to. It seems like it is on their pretty tight though.
 
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