ecu stuck in closed loop. - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

mat.roberts · 05-26-2011, 08:47 AM

Hey guys so for the last 3 days my s14 notchtop would not start for the life of me and every time i turned it over it instantly floods the car. I went in and fixed the timing and that didn't change a thing so for kicks i rolled it down the driveway and bump start it and sure enough it starts up but spewing rich exhaust and a really high idle. I tried adjusting the cas but every time i did the ecu seemed to over ride it and go back to what it was originally at. When it was running i noticed the coolant temp was past the high mark and wasn't moving even though i could feel the rad circulating coolant. I also took it for a quick little ride and the thing would rev then around 2300-2500 rpm it would just jerk violently with retarded timing and possibly fuel cut. I just installed this motor and really want it running and i wanna know if its stuck in closed and if my cts is fucked and needs a new one to run properly or if i can just reset the ecu.
Thanks

codyace · 05-26-2011, 02:40 PM

Hey Mat

Is it throwing any codes? It's certainly sounding like you're in limp mode, so along with the CTS also check that the MAF is ok.

Lastly look at your ECU diagnostic screw...try resetting it that way to see if it works. My personal car actually had that item fail and is currently being repaired.

PoorMans180SX · 05-26-2011, 02:42 PM

Check MAF for sure. Unplug it and see if it runs better. Also, you have your terms confused. Your car is in open loop.

mat.roberts · 05-26-2011, 04:02 PM

Thanks guys well i have a spare head from my old motor Im trying to get a good coolant temp sensor out of that we can try just for kicks but yeah Im in the middle of setting the ecu as we speak so we will see how that goes. Thanks cody glad Im not the only one i still gotta find a spare stock manifold i can use to go external ill let you know how it goes and thanks yeah i figured that out slowly as i searched forums and nobody having closed loop problems Hahahahhahah maybe if there was only one but thanks all help is appreciated!!!

mat.roberts · 05-26-2011, 11:30 PM

So after talking to a few friends and closer inspection of the water temp sensor the one on the new motor is different than that of my original. Also i swapped just the motor and not its original ecu which could be the difference Im looking for here

05-26-2011, 08:47 AM	#1
mat.roberts Leaky Injector Join Date: Feb 2010 Location: edmonton Posts: 92 Trader Rating: (0) Feedback Score: 0 reviews	ecu stuck in closed loop. Hey guys so for the last 3 days my s14 notchtop would not start for the life of me and every time i turned it over it instantly floods the car. I went in and fixed the timing and that didn't change a thing so for kicks i rolled it down the driveway and bump start it and sure enough it starts up but spewing rich exhaust and a really high idle. I tried adjusting the cas but every time i did the ecu seemed to over ride it and go back to what it was originally at. When it was running i noticed the coolant temp was past the high mark and wasn't moving even though i could feel the rad circulating coolant. I also took it for a quick little ride and the thing would rev then around 2300-2500 rpm it would just jerk violently with retarded timing and possibly fuel cut. I just installed this motor and really want it running and i wanna know if its stuck in closed and if my cts is fucked and needs a new one to run properly or if i can just reset the ecu. Thanks __________________ this emoticon describes me.

05-26-2011, 02:40 PM	#2
codyace Post Whore! Join Date: Dec 2004 Location: Poconos, PA Age: 36 Posts: 8,030 Trader Rating: (58) Feedback Score: 58 reviews	Hey Mat Is it throwing any codes? It's certainly sounding like you're in limp mode, so along with the CTS also check that the MAF is ok. Lastly look at your ECU diagnostic screw...try resetting it that way to see if it works. My personal car actually had that item fail and is currently being repaired. __________________ *Want Air Conditioning in your SR20 Swapped car? Check out www.sr20acbrackets.com for more information! Quest Alternator Conversions for SR20!* Check my Group Buy! Tired of lousy internal gates? Go external wastegate with one of my manifolds, Check out my group buy

05-26-2011, 02:42 PM	#3
PoorMans180SX Zilvia.net Advertiser Join Date: Nov 2005 Location: Michigan Age: 33 Posts: 5,431 Trader Rating: (16) Rides Gallery: PoorMans180SX Feedback Score: 16 reviews	Check MAF for sure. Unplug it and see if it runs better. Also, you have your terms confused. Your car is in open loop. __________________ Build: http://zilvia.net/f/showthread.php?t=643065 Friends don't let friends buy knock-offs.

05-26-2011, 04:02 PM	#4
mat.roberts Leaky Injector Join Date: Feb 2010 Location: edmonton Posts: 92 Trader Rating: (0) Feedback Score: 0 reviews	Thanks guys well i have a spare head from my old motor Im trying to get a good coolant temp sensor out of that we can try just for kicks but yeah Im in the middle of setting the ecu as we speak so we will see how that goes. Thanks cody glad Im not the only one i still gotta find a spare stock manifold i can use to go external ill let you know how it goes and thanks yeah i figured that out slowly as i searched forums and nobody having closed loop problems Hahahahhahah maybe if there was only one but thanks all help is appreciated!!! __________________ this emoticon describes me.

05-26-2011, 11:30 PM	#5
mat.roberts Leaky Injector Join Date: Feb 2010 Location: edmonton Posts: 92 Trader Rating: (0) Feedback Score: 0 reviews	So after talking to a few friends and closer inspection of the water temp sensor the one on the new motor is different than that of my original. Also i swapped just the motor and not its original ecu which could be the difference Im looking for here __________________ this emoticon describes me.

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