2004 Lancer Sportback Ralliart AT Build
#1998
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From: So. Jersey (San Diego native)
Edit: So, eliminate the PCV valve and attach a catch can, and plugging the intake manifold? What's going on though...why am I experiencing this now?
Last edited by truthdweller; Mar 18, 2017 at 12:14 PM.
#1999
Just coming at this from uninformed left field: the only thing I can think of that would be pressurizing the crankcase like that is blowby past the pistons. Have you checked for that? (pressurize the cylinder with air via the spark plug hole and observe leak down).
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truthdweller (Mar 20, 2017)
#2001
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From: So. Jersey (San Diego native)
#2003
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From: So. Jersey (San Diego native)
So, apparently, the TB is loose causing the chatter and the other symptoms are yet to be addressed. He sat on it all week without touching it...nice.
I've been bass fishing and enjoying family get togethers, using the wife's car so Im alright, considering...take that Mitsubishi!
#2004
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From: So. Jersey (San Diego native)
Update:
Coolant Temp sensor data checked out fine per shop ( following a lead after getting a response to my YouTube video:
He's wanting to replace valve springs, stating he spoke to a performance shop buddy of his and they are recommending the valve springs be replaced... in that valve float, secondary to week valve springs, may be the cause of my 5-6k rpm power loss...http://www.aa1car.com/library/valve_..._diagnosis.htm
Coolant Temp sensor data checked out fine per shop ( following a lead after getting a response to my YouTube video:
He's wanting to replace valve springs, stating he spoke to a performance shop buddy of his and they are recommending the valve springs be replaced... in that valve float, secondary to week valve springs, may be the cause of my 5-6k rpm power loss...http://www.aa1car.com/library/valve_..._diagnosis.htm
Last edited by truthdweller; Apr 4, 2017 at 04:25 PM.
#2005
I can't imagine it is valve float considering that is well below factory redline. On my old BMW I would get some valve float on a balanced a blueprinted engine, but that was around 7,000 plus RPM.
#2006
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From: So. Jersey (San Diego native)
Valve float occurs when the springs can't keep up with the engine's speed. At high RPM (anything above 5000 RPM), the valves are opening and closing very rapidly. The camshaft rotates at half the speed of the crankshaft, so at 5000 RPM, the cam is spinning around at 2500 RPM, and pushing the valves open over 40 times a second! If the valve springs are weak, the springs may not be able to push the valves all the way shut before the next opening cycle begins. If the valves fail to close, the cylinders will lose compression causing the engine to misfire and lose power." - http://www.aa1car.com/library/valve_..._diagnosis.htm
#2008
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From: So. Jersey (San Diego native)
Here is something else that raises a red flag and that is, when I took the vehicle to have it smoke tested and the timing belt reconfirmed, I was informed that a local machine shop that does head refinishing had a bad reputation for putting out a bad product and ruining engines in the process. Well, when I asked my shop where my head was refinished he stated that very shop. I did not tell him what I was told though. If that is the case, then what symptoms would I be experiencing?
Last edited by truthdweller; Apr 10, 2017 at 10:04 AM.
#2010
Yeah that is really strange. You almost have to assume something was messed up during the install since it didn't happen before the valves were done. I was just saying it is strange for valve float to just start happening out of nowhere.