horrible throttle response w/ my SR - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

LocalStreetHero · 11-10-2007, 01:38 AM

Finally got my SR running good tonight after a lotta trouble with an injector. Well we got it to idle where it should be. Any who, took it out for a test drive and it felt slower than my ka. It had no tourque what's so ever! Turbo is spooling good and boosting high. Low end tourque is no where to be found. No vac lines seem to be leaking.

Back ground info:
91 240
Red top SR with a new gaskets every where
Stock everything on the motor except turbo XS boost controller and HKS BOV (not recirc)
Stock DP with custom 3" DP all the way back exhaust

Timing was set not too long ago when it was just getting to run. Idles fine but like I said throttle respons sucks balls. If I floor it, rpms climb really slow and once its up to about 5 6k it drops really slow as well.

Any help would be extremly appreciated. I was trying to make an event this Sunday but now it seems I can't. Sorry if this post is too broad, but working all day straight till now is making it hard to think and type on my black berry right now. If you need any more info please ask and please help me out.

S13Leprechaun · 11-10-2007, 02:15 AM

whats the condition of your TB and fuel pump?

LocalStreetHero · 11-10-2007, 02:20 AM

Before we dropped the engine the TB was cleaned out, but nothing too extensive and fuel pump is a walbro 255cc.

S13Leprechaun · 11-10-2007, 02:36 AM

check your TPS.. this happened to my friends car not too long ago... it could be off.

toycar · 11-10-2007, 02:43 AM

tps is probably out of spec like he said^ specs are like 1 ohm closed to 10 ohms fully open. also check voltage(supply, signal, grd).

johngriff · 11-10-2007, 08:29 AM

Quote:

Originally Posted by toycar

tps is probably out of spec like he said^ specs are like 1 ohm closed to 10 ohms fully open. also check voltage(supply, signal, grd).

I was kind of excited when i read this.

But alas no.

Its still .45 -> +4v.

LocalStreetHero · 11-10-2007, 02:44 AM

Yes, my friend did have a feeling that's what it could be, but we don't know how to "fix" it. When we pull out the TPS out, the car idles about the same as it does in. How can I fix it?

S13Leprechaun · 11-10-2007, 02:52 AM

never done it... just look at it a while.. i just know the symptoms. sorry man.. hope i was of some help.

LocalStreetHero · 11-10-2007, 03:04 AM

For sure bro, thanks. This is my first full on engine swap ever. I've had 2 KA's but this is my first SR. Shit is so frustrating.

Any1 else if you got info, please help me out.

AznDrftr. · 11-10-2007, 03:55 AM

^im in the same boat with you, first sr, but yea, its fun when it runs right. Until you got problems and what not. Hm, basically check everything, is there proper fuel going, no kinks, or anything blocking? Is bogging or just accelerating very slowly>

statik · 11-10-2007, 08:16 AM

http://static.carvolution.org/files/S14_SR20DET_FSM.pdf

TPS adjustment is on page 271-274

LocalStreetHero · 11-10-2007, 10:29 AM

not so much "bogging down", just really really bad throttle response. RPMS climb really slow, but turbo still spools and BOV works the way it should.

Statik, thanks a lot for that. Unfortunately, i'm not that great with electrical shit, so its going to take me a while to understand what i'm looking at on the FSM. Gotta keep going over it till it makes sense. I will try lookin thru all lines again, and try to make sense of the TPS. All help so far is with out a doubt greatly appreciated, thank you. Time to hit the garage again.

LocalStreetHero · 11-10-2007, 11:53 AM

On page 273, part c...
WTF does "Throttle Sensor CKT" and "Throttle Posi Sen CKT in 'Function Test Mode'" mean??????

Basically if some1 can break down that part for me would be awesome.

LocalStreetHero · 11-10-2007, 02:30 PM

never mind the whole TPS crap. My 2nd cylinder is still NOT getting fuel to it. changed out plugs, coil packs, injectors...Every other cylinder works perfectly fine, except #2. We've checked all the elect stuff on coil pack, injector, everything for #2 and its the exact same readings as all the other ones. WTF!!!? i hate this motor. I dont even know what to do. I"m going to get a compression tester and see if i can learn anything on that. Everything is perfect but for some stupid reason, that cylinder is not getting any fuel whats so ever.

LocalStreetHero · 11-10-2007, 03:26 PM

160 compression on all cylinders. when i pulled out the spark plug that wasn't getting fuel, it had the smell of gas on it, but still a lot of carbon build up. what the duce? While the cars running, if we pull out the #2 coil pack out, the car still runs the same (like shit). it runs the same when we unplug the harness to the injector as well. its obviously getting spark but its still not working.

hmm i'm talking to myself arent i?

fakts13 · 11-10-2007, 09:12 PM

did you use a noid light to make sure the injector is getting the pulse from the ecu? you might have a short in the injector signal wire leaving it open instead of pulsing it.

racepar1 · 11-10-2007, 09:39 PM

what he said^^^ is the most likely cause. I worked on a T-bird that had the same problem and it was the computer though (had an internal short).

LocalStreetHero · 11-11-2007, 12:48 PM

yup, noid light was used and all 4 are working perfectly fine.

I'm going to replace the igniter chip and CTS to see if that helps.

fakts13 · 11-11-2007, 01:24 PM

if you're getting spark like you say you are, replacing the igniter chip probably won't do any good.

11-10-2007, 01:38 AM	#1
LocalStreetHero Zilvia Member Join Date: Aug 2006 Location: SacramentO Age: 40 Posts: 242 Trader Rating: (2) Feedback Score: 2 reviews	horrible throttle response w/ my SR Finally got my SR running good tonight after a lotta trouble with an injector. Well we got it to idle where it should be. Any who, took it out for a test drive and it felt slower than my ka. It had no tourque what's so ever! Turbo is spooling good and boosting high. Low end tourque is no where to be found. No vac lines seem to be leaking. Back ground info: 91 240 Red top SR with a new gaskets every where Stock everything on the motor except turbo XS boost controller and HKS BOV (not recirc) Stock DP with custom 3" DP all the way back exhaust Timing was set not too long ago when it was just getting to run. Idles fine but like I said throttle respons sucks balls. If I floor it, rpms climb really slow and once its up to about 5 6k it drops really slow as well. Any help would be extremly appreciated. I was trying to make an event this Sunday but now it seems I can't. Sorry if this post is too broad, but working all day straight till now is making it hard to think and type on my black berry right now. If you need any more info please ask and please help me out. __________________ herofilms.blogspot.com twitter.com/localstreethero

11-10-2007, 02:20 AM	#3
LocalStreetHero Zilvia Member Join Date: Aug 2006 Location: SacramentO Age: 40 Posts: 242 Trader Rating: (2) Feedback Score: 2 reviews	Before we dropped the engine the TB was cleaned out, but nothing too extensive and fuel pump is a walbro 255cc. __________________ herofilms.blogspot.com twitter.com/localstreethero

11-10-2007, 02:36 AM	#4
S13Leprechaun Zilvia FREAK! Join Date: Jan 2007 Location: 1904 Posts: 1,110 Trader Rating: (0) Feedback Score: 0 reviews	check your TPS.. this happened to my friends car not too long ago... it could be off. __________________ *thurs. knights.*

11-10-2007, 02:44 AM	#7
LocalStreetHero Zilvia Member Join Date: Aug 2006 Location: SacramentO Age: 40 Posts: 242 Trader Rating: (2) Feedback Score: 2 reviews	Yes, my friend did have a feeling that's what it could be, but we don't know how to "fix" it. When we pull out the TPS out, the car idles about the same as it does in. How can I fix it? __________________ herofilms.blogspot.com twitter.com/localstreethero

11-10-2007, 02:52 AM	#8
S13Leprechaun Zilvia FREAK! Join Date: Jan 2007 Location: 1904 Posts: 1,110 Trader Rating: (0) Feedback Score: 0 reviews	never done it... just look at it a while.. i just know the symptoms. sorry man.. hope i was of some help. __________________ *thurs. knights.*

11-10-2007, 02:15 AM	#2
S13Leprechaun Zilvia FREAK! Join Date: Jan 2007 Location: 1904 Posts: 1,110 Trader Rating: (0) Feedback Score: 0 reviews	whats the condition of your TB and fuel pump? __________________ *thurs. knights.*

11-10-2007, 02:43 AM	#5
toycar Join Date: Dec 2005 Location: hawaii Posts: 26 Trader Rating: (0) Feedback Score: 0 reviews	tps is probably out of spec like he said^ specs are like 1 ohm closed to 10 ohms fully open. also check voltage(supply, signal, grd).

11-10-2007, 03:04 AM	#9
LocalStreetHero Zilvia Member Join Date: Aug 2006 Location: SacramentO Age: 40 Posts: 242 Trader Rating: (2) Feedback Score: 2 reviews	For sure bro, thanks. This is my first full on engine swap ever. I've had 2 KA's but this is my first SR. Shit is so frustrating. Any1 else if you got info, please help me out. __________________ herofilms.blogspot.com twitter.com/localstreethero

11-10-2007, 03:55 AM	#10
AznDrftr. BANNED Join Date: Apr 2006 Location: 254 \| Texas. Age: 38 Posts: 2,293 Trader Rating: (3) Rides Gallery: AznDrftr. Feedback Score: 3 reviews	^im in the same boat with you, first sr, but yea, its fun when it runs right. Until you got problems and what not. Hm, basically check everything, is there proper fuel going, no kinks, or anything blocking? Is bogging or just accelerating very slowly>

11-10-2007, 08:16 AM	#11
statik Zilvia FREAK! Join Date: Oct 2003 Location: Long Island, NY Age: 40 Posts: 1,358 Trader Rating: (0) Rides Gallery: statik Feedback Score: 0 reviews	http://static.carvolution.org/files/S14_SR20DET_FSM.pdf TPS adjustment is on page 271-274 __________________ 97 240sx esaarr \| Current Status: SOLD

11-10-2007, 10:29 AM	#12
LocalStreetHero Zilvia Member Join Date: Aug 2006 Location: SacramentO Age: 40 Posts: 242 Trader Rating: (2) Feedback Score: 2 reviews	not so much "bogging down", just really really bad throttle response. RPMS climb really slow, but turbo still spools and BOV works the way it should. Statik, thanks a lot for that. Unfortunately, i'm not that great with electrical shit, so its going to take me a while to understand what i'm looking at on the FSM. Gotta keep going over it till it makes sense. I will try lookin thru all lines again, and try to make sense of the TPS. All help so far is with out a doubt greatly appreciated, thank you. Time to hit the garage again. __________________ herofilms.blogspot.com twitter.com/localstreethero

11-10-2007, 11:53 AM	#13
LocalStreetHero Zilvia Member Join Date: Aug 2006 Location: SacramentO Age: 40 Posts: 242 Trader Rating: (2) Feedback Score: 2 reviews	On page 273, part c... WTF does "Throttle Sensor CKT" and "Throttle Posi Sen CKT in 'Function Test Mode'" mean?????? Basically if some1 can break down that part for me would be awesome. __________________ herofilms.blogspot.com twitter.com/localstreethero

11-10-2007, 02:30 PM	#14
LocalStreetHero Zilvia Member Join Date: Aug 2006 Location: SacramentO Age: 40 Posts: 242 Trader Rating: (2) Feedback Score: 2 reviews	never mind the whole TPS crap. My 2nd cylinder is still NOT getting fuel to it. changed out plugs, coil packs, injectors...Every other cylinder works perfectly fine, except #2. We've checked all the elect stuff on coil pack, injector, everything for #2 and its the exact same readings as all the other ones. WTF!!!? i hate this motor. I dont even know what to do. I"m going to get a compression tester and see if i can learn anything on that. Everything is perfect but for some stupid reason, that cylinder is not getting any fuel whats so ever. __________________ herofilms.blogspot.com twitter.com/localstreethero

11-10-2007, 03:26 PM	#15
LocalStreetHero Zilvia Member Join Date: Aug 2006 Location: SacramentO Age: 40 Posts: 242 Trader Rating: (2) Feedback Score: 2 reviews	160 compression on all cylinders. when i pulled out the spark plug that wasn't getting fuel, it had the smell of gas on it, but still a lot of carbon build up. what the duce? While the cars running, if we pull out the #2 coil pack out, the car still runs the same (like shit). it runs the same when we unplug the harness to the injector as well. its obviously getting spark but its still not working. hmm i'm talking to myself arent i? __________________ herofilms.blogspot.com twitter.com/localstreethero

11-10-2007, 09:12 PM	#16
fakts13 Zilvia Member Join Date: May 2003 Location: socal Posts: 245 Trader Rating: (0) Feedback Score: 0 reviews	did you use a noid light to make sure the injector is getting the pulse from the ecu? you might have a short in the injector signal wire leaving it open instead of pulsing it.

11-10-2007, 09:39 PM	#17
racepar1 Post Whore! Join Date: Jul 2007 Location: Simi Valley, CA Age: 42 Posts: 9,006 Trader Rating: (106) Rides Gallery: racepar1 Feedback Score: 106 reviews	what he said^^^ is the most likely cause. I worked on a T-bird that had the same problem and it was the computer though (had an internal short).

11-11-2007, 12:48 PM	#18
LocalStreetHero Zilvia Member Join Date: Aug 2006 Location: SacramentO Age: 40 Posts: 242 Trader Rating: (2) Feedback Score: 2 reviews	yup, noid light was used and all 4 are working perfectly fine. I'm going to replace the igniter chip and CTS to see if that helps. __________________ herofilms.blogspot.com twitter.com/localstreethero

11-11-2007, 01:24 PM	#19
fakts13 Zilvia Member Join Date: May 2003 Location: socal Posts: 245 Trader Rating: (0) Feedback Score: 0 reviews	if you're getting spark like you say you are, replacing the igniter chip probably won't do any good.