Loss of power after 75%~ throttle... - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

z0iid · 07-19-2004, 05:55 PM

Im not sure how else to describe it. Turbo sounds fine unless I floor it - then it sounds like it is struggling.

I dunno, maybe because of the extra air it needs to compress (in the fmic)?

Basically stock sr20 setup. except hks intake and greddy fmic.

Sound normal?

People who drive it say it feels fine, that it feels and sounds like it would in a new turbo'ed car - no boost spikes or anything.

Doesn't feel right to me though.

Anyone else even know what I am talking about?

Pepperoni · 07-19-2004, 07:21 PM

Since when have you started to notice this?

Dutchmalmiss · 07-20-2004, 01:11 PM

i get the same thing. feels stronger with a light touch, but when i slightly mash on it, it's a bit slower.

Red · 07-20-2004, 02:06 PM

I have been working on tuning my car...

I found that when I was anywhere from 50% to about 75% throttle the car would run at 12/1 afr and when I hit 100% it would drop to 10/1 killing my power... I have tuned that out most the way... but I still need to play with it allot.

This could also be the problem you have...

*MELLO*SOS* · 07-21-2004, 01:00 PM

Hi

I don't have an sr20, but I have this exact problem on my ka24de. It feels like it pulls stronger with 90% throttle from 2k-4k. At 5-6k it feels normal. Occassionaly, it will fix itself for a few minutes.

I've changed the plugs, cleaned the MAF and checked out the TB... I'm thinking it could be a bad MAF or TPS; although since my timing chain is rattling, I've heard that it can cause the cams to "float"... I don't know how true that is, but it could account for the feeling I'm having in my car.

Oh yea, everyone else (including the mechanic) who drives the car insists that it drives fine and "pulls good"..

sr240mike · 07-22-2004, 10:51 AM

It could be you have a boost leak and the turbo is struggling to keep the boost up, or the turbo bearings are starting to go. The ecu could be detecting knock and is sending it into the safety maps which kills power, but that wouldn't explain the turbo sound.

z0iid · 07-22-2004, 11:11 AM

u said..

I found that when I was anywhere from 50% to about 75% throttle the car would run at 12/1 afr and when I hit 100% it would drop to 10/1 killing my power... I have tuned that out most the way... but I still need to play with it allot.

what do you mean by tuned that out most the way? timing, ecu, boost controler....elaborate

Red · 07-22-2004, 02:59 PM

ummm all of the above...

I have the E-manage and E-01... So I just change it while I drive...

So yeah I change everything... I'm still changing stuff...

07-19-2004, 05:55 PM	#1
z0iid Leaky Injector Join Date: May 2004 Location: Bay Area Age: 38 Posts: 85 Trader Rating: (0) Feedback Score: 0 reviews	Loss of power after 75%~ throttle... Im not sure how else to describe it. Turbo sounds fine unless I floor it - then it sounds like it is struggling. I dunno, maybe because of the extra air it needs to compress (in the fmic)? Basically stock sr20 setup. except hks intake and greddy fmic. Sound normal? People who drive it say it feels fine, that it feels and sounds like it would in a new turbo'ed car - no boost spikes or anything. Doesn't feel right to me though. Anyone else even know what I am talking about? __________________ Anyone down for causing a freak gasoline fight accident?

07-19-2004, 07:21 PM	#2
Pepperoni Zilvia Addict Join Date: Jun 2003 Location: norcal Posts: 750 Trader Rating: (0) Feedback Score: 0 reviews	Since when have you started to notice this? __________________ Turbo piping, Intakes and More: http://www.pipingpro.com

07-20-2004, 01:11 PM	#3
Dutchmalmiss Post Whore! Join Date: Apr 2003 Location: Socal (323) Age: 35 Posts: 3,475 Trader Rating: (13) Feedback Score: 13 reviews	i get the same thing. feels stronger with a light touch, but when i slightly mash on it, it's a bit slower. __________________ Pignose, biaaatch.

07-20-2004, 02:06 PM	#4
Red Zilvia Addict Join Date: Feb 2002 Location: Vancouver, WA - Portland, OR Age: 40 Posts: 734 Trader Rating: (0) Feedback Score: 0 reviews	I have been working on tuning my car... I found that when I was anywhere from 50% to about 75% throttle the car would run at 12/1 afr and when I hit 100% it would drop to 10/1 killing my power... I have tuned that out most the way... but I still need to play with it allot. This could also be the problem you have... __________________ http://www.cardomain.com/memberpage/509537 http://www.imagestation.com/album/?id=4287415487 http://www.zilvia.net/f/showthread.php?t=21036

07-22-2004, 10:51 AM	#6
sr240mike Zilvia FREAK! Join Date: Apr 2004 Location: California, Norcal biiaatch Posts: 1,185 Trader Rating: (0) Feedback Score: 0 reviews	It could be you have a boost leak and the turbo is struggling to keep the boost up, or the turbo bearings are starting to go. The ecu could be detecting knock and is sending it into the safety maps which kills power, but that wouldn't explain the turbo sound. __________________ TWO IN THE COOT, ONE IN THE POOT

07-21-2004, 01:00 PM	#5
MELLOSOS* LAID OUT Join Date: Mar 2004 Location: LAS VEGAS Age: 39 Posts: 2,015 Trader Rating: (1) Rides Gallery: MELLO*SOS Feedback Score: 1 reviews	Hi I don't have an sr20, but I have this exact problem on my ka24de. It feels like it pulls stronger with 90% throttle from 2k-4k. At 5-6k it feels normal. Occassionaly, it will fix itself for a few minutes. I've changed the plugs, cleaned the MAF and checked out the TB... I'm thinking it could be a bad MAF or TPS; although since my timing chain is rattling, I've heard that it can cause the cams to "float"... I don't know how true that is, but it could account for the feeling I'm having in my car. Oh yea, everyone else (including the mechanic) who drives the car insists that it drives fine and "pulls good"..

07-22-2004, 11:11 AM	#7
z0iid Leaky Injector Join Date: May 2004 Location: Bay Area Age: 38 Posts: 85 Trader Rating: (0) Feedback Score: 0 reviews	u said.. I found that when I was anywhere from 50% to about 75% throttle the car would run at 12/1 afr and when I hit 100% it would drop to 10/1 killing my power... I have tuned that out most the way... but I still need to play with it allot. what do you mean by tuned that out most the way? timing, ecu, boost controler....elaborate __________________ Anyone down for causing a freak gasoline fight accident?

07-22-2004, 02:59 PM	#8
Red Zilvia Addict Join Date: Feb 2002 Location: Vancouver, WA - Portland, OR Age: 40 Posts: 734 Trader Rating: (0) Feedback Score: 0 reviews	ummm all of the above... I have the E-manage and E-01... So I just change it while I drive... So yeah I change everything... I'm still changing stuff... __________________ http://www.cardomain.com/memberpage/509537 http://www.imagestation.com/album/?id=4287415487 http://www.zilvia.net/f/showthread.php?t=21036

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