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Mike09
Posts: 444
Joined: Fri Aug 09, 2002 5:27 pm

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Hi, I searched already and nothing relevant came up.I have a s13 restop sr w/ GreddyTD06 turbine ket on it.

My problems are that at WOT my boost gauge reads .6-.7 bar but the car doesn't accelaerte at all. At 1/4 throttle the car acceletates moderatly quick as it builds boost but it's actually slower at WOT. Also I have a intermittent misfire at approx 2700-3000. Any thoughts on what could be wrong.


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PhopsonNY
Posts: 532
Joined: Sun Oct 26, 2003 9:34 am

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You may have a broken exhaust mani stud thus leaking boost especially under high boost.

This happened to me so check it out. The way I discovered it was I seafoamed the car and noticed the white smoke coming from that area.

It could be other things like a bad turbo, coilpacks etc.

good luck and let us know what you find out

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cheapscheisst
Posts: 421
Joined: Thu Nov 30, 2006 12:42 pm
Car: 1996 240sx w/ Kouki front end

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sounds like you could be running rich at WOT. do you have an a/f gauge?

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S13FASTBACKSR
Posts: 2177
Joined: Sun Nov 27, 2005 10:28 am
Car: '92 Fastback SR powered

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I was thinking a slipping clutch until you said it was misfiring..maybe it is a slipping clutch and the misfiring is a seperate problem..when you have a loss of power and misfiring it is a good chance your timing is off..check that and if it checks out good check your spark plugs to make sure they are gapped at what they should be. check your tps voltage at idle and w.o.t....Voltage should be .45v-.55v at idle and 4.5v at w.o.t. also check your maf voltage..you should read a 12v wire 5v wire and then you have your ground..are you running rich at all? also check your ecu for any stored codes

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oki_bum
Posts: 418
Joined: Wed Feb 15, 2006 11:23 am
Car: SR Powered 1990 240SX

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was wondering if you figured out the problem?

Mike09
Posts: 444
Joined: Fri Aug 09, 2002 5:27 pm

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Well, it's not a slipping clutch or broken exhaust studs. Or any other leak in the exhaust, or turbo.I still have to check the coilpacks, tps, maf, and A/F ratio but there's too much snow to go work on it the last couple days so i'll check those tomorrow or the day after!! Thank you

Mike09
Posts: 444
Joined: Fri Aug 09, 2002 5:27 pm

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Update....Well I swapped plugs, adjusted timing, set fuel psi to OEM spec(ADJUSTABLE REG.), and there is still a difinate problem. after fixing all that I drove it and it drove better but it still has the misfire at 2700-3000rpm and it's pretty bad, and I can acelerate at WOT now but it bogg's/ can't rev higher than 5000-5300 at WOT. After a week or so I removed plugs again to check gap and adjust less but the plugs were BLACK. I know this means I'm running rich but I still have stock injectors??? How could it run rich with a big *** turbo and stock injectors????? Any thoughts

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S13FASTBACKSR
Posts: 2177
Joined: Sun Nov 27, 2005 10:28 am
Car: '92 Fastback SR powered

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just because the injectors are stock doesnt mean you cant run rich or lean...your injectors may be sticking open causing too much fuel/ richness..are any of your spark plugs a lot blacker than the others?

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efrain240sx
Posts: 612
Joined: Fri Jun 17, 2005 12:14 pm
Car: 1992 nissan 240sx HB

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I had a similar problem, it would always back fire like crazy and at WOT it felt like the timing would get retarded like crazy, so it turned out that it was my knock sensor that wasn't it working right. So I changed it out and now it works peachy.

nonvtecaccord
Posts: 224
Joined: Mon Dec 23, 2002 2:50 pm

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did it run right before you put the turbo on? Has the car ever run right? or did it just start doing this?

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Sil80315
Posts: 1084
Joined: Mon Jan 30, 2006 4:34 pm
Car: 1991 Nissan 240sx
Contact:

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after checking out this common "backfireing, sputtering at 2-3k rpm" I do believe it has to do with TPS and knock sensor. Deffenetly check out the voltage on your TPS cause even if you mash the gas..the TPS will tell the ecu that your not at WOT. also make sure you do a boost leak test. If you want I can tell you how to make the cuplair or you can just do research on how to make it

It pays off big time to do a boost leak test cause you will find a ton of leaks that all cause the car to act up, I know people that are still hunting down small leaks that you hardly even notice but it does effect your motor.

Also if you did a turbo upgrade, why would you run stock injectors? does this mean your running stock maf and stock ecu? cause 7 psi from a bigger turbo is alot differen't then 7 psi from a stock t25 because the bigger turbo moves a higher amount of air into the motor so really its like 11 psi you get from a t25 to a 7 psi from a bigger turbo.

if you want give me a shout on AIM, Ive been dealin with these problems for awhile and I know a few things i did to smooth them out.

AIM is sil80315

Mike09
Posts: 444
Joined: Fri Aug 09, 2002 5:27 pm

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I'll check TPS and knock sensor and let you guys know. Thanks all!!And it did run right but i had the motor out to do some repairs and it hasn't run rite since.

sd2nola
Posts: 45
Joined: Mon Mar 27, 2006 6:53 pm
Car: 1993 240sx

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hey man...it sounds like you got about the same problem i do. if you find out the problem could you let me know? aslo...make sure you check vacume leaks.

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sunnys14
Posts: 1600
Joined: Sun Dec 05, 2004 8:59 pm
Car: S14

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dude i have the same prob also!!

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9240sx
Posts: 2676
Joined: Wed Dec 10, 2003 4:06 am
Car: What i believe to be the cleanest s13 in the world.

SR20DET + RS*R-Apexi-Nismo-Trust-HKS= 100% pure love
Location: New Mexico

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Sounds like igniton timming is retarded to me.

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Sil80315
Posts: 1084
Joined: Mon Jan 30, 2006 4:34 pm
Car: 1991 Nissan 240sx
Contact:

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Yeah and do timing on it aswell!

[email protected]
Posts: 1
Joined: Wed Mar 07, 2007 1:19 pm
Car: 90 sileighty, SR, BOLT ONS, CUSTOM SKYLINE EXHAUST, IT LOOKS PURPLE BUT ITS REALLY BLUE
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I HAVE THE SAME PROBLEM....

I CHANGE SPARK PLUGS, I THOUGHT IT WAS TIRES, THE ONLY THING I NOTICE IS THAT MY VOLTS DROP FROM TIME TO TIME....

MY BOOST BUT NO POWER HAPPENS SOMETIMES.. IF IT WAS ALL THE TIME I WOULD HAVE FOUND THE PROBLEM (MAYBE) BUT SINCE IT ONLY HAPPENS SOMETIMES, I CANT NEVER PIN POINT IT.. IM GOING TO CHANGE MY 02 SENSOR, I CLEAN MY MAF... AND MY FILTER...

I HAVE A BOOST gauge SO I SEE IM IN FULL BOOST BUT NO POWER, AND I DONT HAVE ANY LEAKS (I FIXED THEM ALL, MAYBE)... AND I NOTICE THAT IF I DONT BOOST THEN IT RUNS FINE. BUT PASS 2PSI... DOWN HILL

goj_cloud
Posts: 487
Joined: Sat May 27, 2006 7:17 pm

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see people will slap on a huge turbo and put bigger injectors but they dont get tuning, and people wonder why their cars run ****ty.

did you get proper tuning after u put the turbo on?

Mike09
Posts: 444
Joined: Fri Aug 09, 2002 5:27 pm

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It is tuned and has bigger injectors but i removed them and went to the stock system because i was worried that was the problem. Either way it turned out to be timing. I was setting timing and unfortunatly to my error I was using a ****ty refernce for the timing marks. after setting to the proper timing car runs fine at high RPM again.

Although I still have a misfire at 2700-3000RPM that has not changed at all even with everything I fixed so far. Its very noticable on daily driving.Any other thoughts on this.

goj_cloud
Posts: 487
Joined: Sat May 27, 2006 7:17 pm

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try sea foam

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S13FASTBACKSR
Posts: 2177
Joined: Sun Nov 27, 2005 10:28 am
Car: '92 Fastback SR powered

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do you have an adjustable fpr? are you running rich at all?

Mike09
Posts: 444
Joined: Fri Aug 09, 2002 5:27 pm

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I do but I lowered it back to stock FPR. That was one of the first things I did!!!

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S13FASTBACKSR
Posts: 2177
Joined: Sun Nov 27, 2005 10:28 am
Car: '92 Fastback SR powered

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at stock fuel pressure my mildly modded sr does not run right..it would misfire at the same rpm range yours is and then again at higher rpms..i have mine set at 52psi right now..now on the other hand a guy in my town with a 500whp sr has a stock fpr which means stock fuel pressure and his runs fine..so idk what the deal is with that but just mess around with your fuel pressure see if it gets better or worse

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sr28
Posts: 89
Joined: Sun Jun 17, 2007 9:59 pm
Car: 1990 240sx hatchback

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i have the same damn problem.. my turbo spoools like a crazy ***** and im moving at 10mph but the sounds feels like 80mph.. so the people watching me crawl along probably see 15mph instead of 10..

Greg_z32
Posts: 4
Joined: Thu Aug 23, 2018 11:46 am
Car: 300zx TT

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I know this may be an old post but did you figure out what’s going on? Because my car is doing same thing

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MeanGreenS13
Posts: 3483
Joined: Sat Aug 20, 2005 12:59 pm
Car: 2011 Chevrolet Silverado 2500HD
Location: Ocala, FL
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This may seem like a dumb question, but what do you gap your plugs at?

LONG ago, I had an issue with blowing out spark because my gap was too wide


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