WTF? why am I building boost in neutral now?
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WTF? why am I building boost in neutral now?
Ok,
Today I started up my car and it was idling kinda funny, like rough but it even itself out after lettting it warm up for 5 minutes, so as I give it some revs, it usually just revs up from vacuum to 0 psi, today it flys over 5 psi while I"m in neutral, does that make sense and why is it doing that? I checked all the vacuum lines and they seem to be fine.
Today I started up my car and it was idling kinda funny, like rough but it even itself out after lettting it warm up for 5 minutes, so as I give it some revs, it usually just revs up from vacuum to 0 psi, today it flys over 5 psi while I"m in neutral, does that make sense and why is it doing that? I checked all the vacuum lines and they seem to be fine.
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From: Austin, Texas, US
Re: WTF? why am I building boost in neutral now? (reXem)
A turbo will not build boost unless under load, neutral there is no load and therefore it shouldnt build any boost.
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From: Traverse City, Michigan, USA
Re: WTF? why am I building boost in neutral now? (ImAcracker)
A turbo will not build boost unless under load, neutral there is no load and therefore it shouldnt build any boost.
Ok this doesnt make any sense to me. Why would you not build any boost in neutral without a load? Can someone please explain this to me further. I would really like to know. Thanks.
Ok this doesnt make any sense to me. Why would you not build any boost in neutral without a load? Can someone please explain this to me further. I would really like to know. Thanks.
Did this make any sense???
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From: Where Geos Go Fast, 95355
Re: WTF? why am I building boost in neutral now? (Tinker219)
you hit redline before boost can come online... you'll notice if you blip the throttle near or above your boost point while under load, you will make boost. good way to launch with boost... hehe
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From: WI, USA
Re: WTF? why am I building boost in neutral now? (lazerus)
Oh mick, still having problems with your setup. Sorry to hear that, I would make sure that your boost guage is not messed up.
let me know if i can do anything to help !
let me know if i can do anything to help !
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From: 604 whp NorCaL
Re: WTF? why am I building boost in neutral now? (reXem)
it's not supposed to build any boost because thats the way map sensor based fuel injection works. when theres no load detected by the map sensor the ecu doesnt add very much fuel as the motor revs, and without the fuel there isn't enough exhaust energy to spool the turbo. I would make sure your connections to your map sensor are still sound, and if you have check valves then make sure they are functioning properly.
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From: Traverse City, Michigan, USA
Re: WTF? why am I building boost in neutral now? (SEFI8LOxCivic)
it's not supposed to build any boost because thats the way map sensor based fuel injection works. when theres no load detected by the map sensor the ecu doesnt add very much fuel as the motor revs, and without the fuel there isn't enough exhaust energy to spool the turbo. I would make sure your connections to your map sensor are still sound, and if you have check valves then make sure they are functioning properly.
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From: Dallas, Tx, USA
Re: WTF? why am I building boost in neutral now? (Tinker219)
lol did anyone think it could be the boost gauge, I say this b/c I saw my gauge was at 5 psi when I was at like 1/4 throttle which shouldnt have built boost, then let off and the vacum was only at 10, I turned the car off and back on and the gauge auto zeroed and it was fine.
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Re: WTF? why am I building boost in neutral now? (foozball-26)
well funny thing is that the boost gauge works exactly the same as it did before, vacuum is nice and consistent and when I'm under load the boost gauge works fine as before, nice steady movement to 8 psi
It's a greddy turbo kit for a gsr BTW
But in 3 turboed cars that I've had, it's never done this before, even when I put the turb kit on this one, it never happened, Until yesterday
It only "builds" boost when I really get on it, slight revs or hard revs will up to 5k will only bring up to 0 psi, but if I floor it to about 6k, boost rises fast.......hmmm, who knows?
It's a greddy turbo kit for a gsr BTW
But in 3 turboed cars that I've had, it's never done this before, even when I put the turb kit on this one, it never happened, Until yesterday
It only "builds" boost when I really get on it, slight revs or hard revs will up to 5k will only bring up to 0 psi, but if I floor it to about 6k, boost rises fast.......hmmm, who knows?
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From: Where Geos Go Fast, 95355
Re: WTF? why am I building boost in neutral now? (slwazgsr)
are you getting a TON of extra fuel? it can cause boost to come online by "slightly" bogging the engine down.
and about the map sensor thing... uhhh right. Map sensors work off pressure not load, it detects pressure nothing else.
when you revv your car, generally you have close to 0 vacuum. same thing when under load. (of course unless you are turbocharged)
ANYone who has a turbo car... get it warmed up, stick it in neutral and REVV it up over and over again quite fast, tell me if you build boost pressure....
i'll make a vid if i haveta
[Modified by lazerus, 7:40 AM 1/19/2003]
and about the map sensor thing... uhhh right. Map sensors work off pressure not load, it detects pressure nothing else.
when you revv your car, generally you have close to 0 vacuum. same thing when under load. (of course unless you are turbocharged)
ANYone who has a turbo car... get it warmed up, stick it in neutral and REVV it up over and over again quite fast, tell me if you build boost pressure....
i'll make a vid if i haveta
[Modified by lazerus, 7:40 AM 1/19/2003]
Thread Starter
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Re: WTF? why am I building boost in neutral now? (lazerus)
I am getting a SHIET load of fuel, I run rich as hell with my current fuel management (too long to explain) so I'm waiting for my alternative to come from Cheetah this week and hopefully that solves my problems
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From: Blacksburg, VA
Re: WTF? why am I building boost in neutral now? (Tinker219)
OK, picture spraying water at a pinwheel. if the pinwheel has no resistance, or "load" on it, then the water will keep spinning the pinwheel faster and faster. Now put a load on it(put a stick in the spokes), and the water that was spraying on the pinwheel will now spray all over the place. The same is true with pressurized air going into the engine. It will spin the engine faster and faster until you put a load on it. Then when a load is reached, air is "spraying all over" inside the intake manifold, creating boost.
Did this make any sense???
Did this make any sense???
bad analogy, but i cant think of a better one right now
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From: Austin, Texas, US
Re: WTF? why am I building boost in neutral now? (Tinker219)
A turbo will not build boost unless under load, neutral there is no load and therefore it shouldnt build any boost.
Ok this doesnt make any sense to me. Why would you not build any boost in neutral without a load? Can someone please explain this to me further. I would really like to know. Thanks.
OK, picture spraying water at a pinwheel. if the pinwheel has no resistance, or "load" on it, then the water will keep spinning the pinwheel faster and faster. Now put a load on it(put a stick in the spokes), and the water that was spraying on the pinwheel will now spray all over the place. The same is true with pressurized air going into the engine. It will spin the engine faster and faster until you put a load on it. Then when a load is reached, air is "spraying all over" inside the intake manifold, creating boost.
Did this make any sense???
Ok this doesnt make any sense to me. Why would you not build any boost in neutral without a load? Can someone please explain this to me further. I would really like to know. Thanks.
OK, picture spraying water at a pinwheel. if the pinwheel has no resistance, or "load" on it, then the water will keep spinning the pinwheel faster and faster. Now put a load on it(put a stick in the spokes), and the water that was spraying on the pinwheel will now spray all over the place. The same is true with pressurized air going into the engine. It will spin the engine faster and faster until you put a load on it. Then when a load is reached, air is "spraying all over" inside the intake manifold, creating boost.
Did this make any sense???
[Modified by ImAcracker, 11:48 PM 1/19/2003]
[Modified by ImAcracker, 11:49 PM 1/19/2003]
Joined: Dec 2001
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From: Long Island, NY, USA
Re: WTF? why am I building boost in neutral now? (ImAcracker)
yea i've never seen any turbo hondas around here build boost in neutral (myself included). a guy i knew with a sr20det sentra could boost in neutral tho. maybe difference in using MAP or MAF makes the difference? any eclipses build boost in neutral? do they use MAP or MAF? just curious
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From: Columbia, Beaufort,, SC, USA
Re: WTF? why am I building boost in neutral now? (Pengo)
it will build boost. mine does wit hthe t3/t4.. not over 1-2 psi but it still does.. if it doesnt why doesnt the BOV blow off? especailly on smaller turbos..
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From: Columbia, Beaufort,, SC, USA
Re: WTF? why am I building boost in neutral now? (SEFI8LOxCivic)
ahh i see.. well mine sees 1-2 psi and i get the cool chicken sound from the bov (hks from japandy= broke and sounds like a chicken cause the small vavle doesnt open cause the shaft scored like a bitch)