2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

4000rpm jolt of furry

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Old May 28, 2004 | 03:01 PM
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87RX7TII's Avatar
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4000rpm jolt of furry

OK the car is past the breakin period and Im slowly pushing the car harder and harder (im not going above 4.5rpms yet though until i get a new fuel pump.

Well the problem is when I get past the 3800 rpm hesitation. crusing at 4k the car is fine... slightly tap the throttle anymore and my head gets pushed into the headrest. Its like a surge of power but almost too much power...
is this compressor surge or boost creep x5.
I'm not trying to hit boost at 4k but for all I know I might be. The car just jumps forward really hard with no real throttle increase.
???
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Old May 28, 2004 | 03:10 PM
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my guess would be ur turbos kicken in
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Old May 28, 2004 | 03:17 PM
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Wait, why is this a problem?
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Old May 28, 2004 | 03:42 PM
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i think he thinks he might be running lean there and gas is more volatile when it gets thin ie more power but it can also cause detonation reeal easy when its too lean in a vapor way wich spells death for a rotary
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Old May 28, 2004 | 03:50 PM
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Re: 4000rpm jolt of furry

Originally posted by 87RX7TII
I'm not trying to hit boost at 4k but for all I know I might be.
Maybe you should look at your boost gauge? That might tell you.
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Old May 28, 2004 | 05:03 PM
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Originally posted by pyrojunkie
Wait, why is this a problem?
my thoughts exactly
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Old May 28, 2004 | 05:05 PM
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Originally posted by gerbraldy
my thoughts exactly
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Old Jun 1, 2004 | 01:12 PM
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My boost guage is busted, has been since the car broke down... I'm waiting to pick up a new gauge to install on my A pillar along with my new boost one...

it seems to much of a kick for the turbo
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Old Jun 1, 2004 | 01:17 PM
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i have a s5 turbo and im at full boost by 4000 rpm, the car is pretty much stock too
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Old Jun 3, 2004 | 07:55 AM
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"i think he thinks he might be running lean there and gas is more volatile when it gets thin ie more power but it can also cause detonation reeal easy when its too lean in a vapor way wich spells death for a rotary"

Thats the exact reasoning for my worrying..
I have very little turbo kick then all of a sudden WHAM!
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Old Jun 3, 2004 | 08:08 AM
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Originally posted by 87RX7TII
My boost guage is busted, has been since the car broke down... I'm waiting to pick up a new gauge to install on my A pillar along with my new boost one...

it seems to much of a kick for the turbo
Dude if your car is acting up, go easy on it till you get a boost gauge. You NEVER run a turbo car without one.

-Joe
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Old Jun 3, 2004 | 08:26 AM
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oh dont worry im not pushing it hard...
I'm just trying to fix the 3800rpm hesitation and I just hit 4k once in a while.
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Old Jun 3, 2004 | 08:39 AM
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Maybe your secondary throttle plates are sticking and opening very rapidly when they unstick them self.

James
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Old Jun 8, 2004 | 02:14 PM
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well i have my secondary throttle plates tied open so i dont think thats it either.....But I have a update on whats going on...
When I'm driving along at 4000rpms and not advancing the throttle at all the car runs fine but when I slightly push it at 4k the car bucks and kicks and it backfires like a drumroll. I know its not supposed to backfire like that so something is wrong...I have slightly fixed my 3800rpm hesitation by grounding a few things under the hood but at times it still shows up

If im driving along and i go past 4k in a contant (slow) motion there is no kick or bucking
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Old Jun 10, 2004 | 07:59 AM
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I find now the car has a high pitch whistling more then a wooshing... does this sound like something particular?
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Old Jun 10, 2004 | 09:09 AM
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I think you missed what I was saying.

There are two sets of secondary throttle plates on a stock throttle body. The first set the air passes by is the set that is directly connected to the throttle cable and moves with it at all times.

The set that you forced open is the ones that are controlled by the thermowax. And after the wax melts they move just like the main secondary plates

I was saying you should check for smooth operation of those plates.

James
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Old Jun 10, 2004 | 11:37 AM
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alright i'll do that
thanks for clearing that up James!
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