Low Idle, 5k Rev Limit - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

AxiS14 · 12-16-2008, 10:08 AM

I'm having a problem with my 95 240sx. It has a KA24DE, I was having hard starting problems and i found a vacuum line on the top of the EGR valve to have come off. So i put it back on and seems to start fine now. but i still have a problem with not being able to rev above 5k RPM. It has an auto ecu which i dont think would cause this problem because i had an auto ECU in my 87 turbo supra with no problems. Also after my car warms up and i come to a stop the idle drops to about 500 rpm and the car shakes a little bit. I'm thinking maybe my MAF is dirty.

I bought the car about 3 weeks ago and the guy that had it before me threw a CAI on it as long as an exhaust. There is a sensor inside of the filter that i'm not sure what it is. I'm thinking it is maybe intake air temp. not sure if any of this info is helpful or not. As said before the car wont rev over 5k rpm, it kind of feels like there is slight fuel cut like if i was over boosting ( but im not turbo....) not sure what is going on. i'm ordering a manual ecu this weekend to get that dam check engine light off. thx again

playastarkz123 · 12-16-2008, 12:03 PM

try cleaning out the maf, and check the wiring, make sure everything is grounded good and such

96Turbo · 12-16-2008, 12:07 PM

that sensor thing you're referring to is the MAF (mass airflow sensor)

sounds like that's what's causing your problem. check your wiring as playastarkz123 suggested

AxiS14 · 12-17-2008, 06:03 PM

The CAI was put together all fucked up. I found a 2 wire sensor inside of the actual cone filter. I'm not too familiar with the MAF system. I'm going to check the wires as far back as i can. from what i saw the wires seemed to be fine but i didnt check them all the way back trough the harness because i didnt really have time. I'm beginning to think that the whole MAF is going bad im thinking of buying another one from this place called Sunrise Nissan for 75 dollars. The only question that i have is where is this 2 wire sensor that comes off of the MAF sensor wiring suppose to go? Before the actual MAF or after. And If i buy a new MAF adapter to use the cone filter will if have a spot for me to bolt this sensor instead of shoving it inside of the filter?

alzahakar · 12-18-2008, 12:32 AM

OK. A MAF looks like a short black piece of pipe with a black box on the side. I don't think it would fit inside any cone filter you would find on a KA. If the sensor you found in the cone filter is small, two wire and has two screw holes, it's the Intake Temp Sensor. I don't know how important it is, but when I got my S14, the wires were torn off the sensor and my car runs fine. Now I'm kinda interested if its really important.

AxiS14 · 12-19-2008, 09:07 AM

Quote:

Originally Posted by alzahakar

OK. A MAF looks like a short black piece of pipe with a black box on the side. I don't think it would fit inside any cone filter you would find on a KA. If the sensor you found in the cone filter is small, two wire and has two screw holes, it's the Intake Temp Sensor. I don't know how important it is, but when I got my S14, the wires were torn off the sensor and my car runs fine. Now I'm kinda interested if its really important.

Lol i know what a MAF looks like. I was just curious about the small 2 wire sensor with the 2 screw holes on it. That was the sensor i was talking about being inside of the filter. Well im goin to order a new MAF today. Hopefully that will fix it.

G35ttbaconboy · 12-19-2008, 09:19 AM

If buying a new MAF dose not help you being able to go above 5 check if your fuel lines are connected right cause that happened to me once it was corrected wrong and it worked but could not redline

AxiS14 · 12-19-2008, 07:34 PM

Quote:

Originally Posted by G35ttbaconboy

If buying a new MAF dose not help you being able to go above 5 check if your fuel lines are connected right cause that happened to me once it was corrected wrong and it worked but could not redline

iight koo ill check that after. The guy i bought it from had just put a new fuel pump in he said, so maybe he screwed it up. Might have a leak somewhere aswell because i smell gas getting dumped at cold start and i know these things dont have cold start injectors. So maybe the return line is leaking i dunno im going to have to check this out soon too bad we got slammed with snow today.

AxiS14 · 01-15-2009, 08:25 PM

So its been 3 weeks now still have the same problems. i bought a MAF from a friend that worked and it didnt solve my issues. So 2 days ago at work i lifted the hood and was staring at my engine i decided to sit and listen to the engine while i pulled each injector out....#1 pulled idle dropped.....#2 pulled idle dropped...#3 pulled idle dropped.....#4 pulled...nothin changed... I FOUND IT!!! i took a screwdriver i had and put my ear to the plastic end and put the tip of it on the injector to listen for the pulses....very faintly compared to the other injectors, so i think its dying on me. I have 2 injectors on the way should be here by tuesday. I know this will fix my idle problem and my bogging undera 1/4 tank of gas. But the real question is, will this fix my rev limit?

cotbu · 01-15-2009, 08:34 PM

did you ever? check your ecu for codes... this will most likely fix the 5k limit also, but it was limiting rpm to protect the engine.

AxiS14 · 01-16-2009, 10:00 AM

Quote:

Originally Posted by cotbu

did you ever? check your ecu for codes... this will most likely fix the 5k limit also, but it was limiting rpm to protect the engine.

The only code i have is for the A/T diag communication, since it was swapped to a 5 speed and still has the A/T ECU. I'm going to get a 5 speed ECU just to get rid of this light. But yea i was thinking it was trying to save the engine also i just wasnt sure. Thx

01-15-2009, 08:34 PM	#10
cotbu Post Whore! Join Date: Sep 2005 Location: SWFL Age: 50 Posts: 3,318 Trader Rating: (3) Feedback Score: 3 reviews	did you ever? check your ecu for codes... this will most likely fix the 5k limit also, but it was limiting rpm to protect the engine. __________________ LoverTechnologies "Half Broken Things!"

12-16-2008, 10:08 AM	#1
AxiS14 Join Date: Dec 2008 Location: Worcester MA Age: 39 Posts: 19 Trader Rating: (0) Feedback Score: 0 reviews	Low Idle, 5k Rev Limit I'm having a problem with my 95 240sx. It has a KA24DE, I was having hard starting problems and i found a vacuum line on the top of the EGR valve to have come off. So i put it back on and seems to start fine now. but i still have a problem with not being able to rev above 5k RPM. It has an auto ecu which i dont think would cause this problem because i had an auto ECU in my 87 turbo supra with no problems. Also after my car warms up and i come to a stop the idle drops to about 500 rpm and the car shakes a little bit. I'm thinking maybe my MAF is dirty. I bought the car about 3 weeks ago and the guy that had it before me threw a CAI on it as long as an exhaust. There is a sensor inside of the filter that i'm not sure what it is. I'm thinking it is maybe intake air temp. not sure if any of this info is helpful or not. As said before the car wont rev over 5k rpm, it kind of feels like there is slight fuel cut like if i was over boosting ( but im not turbo....) not sure what is going on. i'm ordering a manual ecu this weekend to get that dam check engine light off. thx again

12-16-2008, 12:03 PM	#2
playastarkz123 Zilvia Junkie Join Date: Apr 2007 Location: New Jersey Age: 35 Posts: 328 Trader Rating: (8) Feedback Score: 8 reviews	try cleaning out the maf, and check the wiring, make sure everything is grounded good and such __________________ www.teamirrational.wordpress.com

12-16-2008, 12:07 PM	#3
96Turbo Zilvia FREAK! Join Date: Nov 2007 Location: AZ Age: 36 Posts: 1,315 Trader Rating: (11) Feedback Score: 11 reviews	that sensor thing you're referring to is the MAF (mass airflow sensor) sounds like that's what's causing your problem. check your wiring as playastarkz123 suggested

12-17-2008, 06:03 PM	#4
AxiS14 Join Date: Dec 2008 Location: Worcester MA Age: 39 Posts: 19 Trader Rating: (0) Feedback Score: 0 reviews	The CAI was put together all fucked up. I found a 2 wire sensor inside of the actual cone filter. I'm not too familiar with the MAF system. I'm going to check the wires as far back as i can. from what i saw the wires seemed to be fine but i didnt check them all the way back trough the harness because i didnt really have time. I'm beginning to think that the whole MAF is going bad im thinking of buying another one from this place called Sunrise Nissan for 75 dollars. The only question that i have is where is this 2 wire sensor that comes off of the MAF sensor wiring suppose to go? Before the actual MAF or after. And If i buy a new MAF adapter to use the cone filter will if have a spot for me to bolt this sensor instead of shoving it inside of the filter?

12-18-2008, 12:32 AM	#5
alzahakar Zilvia Member Join Date: Aug 2008 Location: San Antonio, TX Age: 43 Posts: 196 Trader Rating: (4) Feedback Score: 4 reviews	OK. A MAF looks like a short black piece of pipe with a black box on the side. I don't think it would fit inside any cone filter you would find on a KA. If the sensor you found in the cone filter is small, two wire and has two screw holes, it's the Intake Temp Sensor. I don't know how important it is, but when I got my S14, the wires were torn off the sensor and my car runs fine. Now I'm kinda interested if its really important.

12-19-2008, 09:19 AM	#7
G35ttbaconboy Leaky Injector Join Date: Dec 2008 Location: Queens Posts: 50 Trader Rating: (0) Feedback Score: 0 reviews	If buying a new MAF dose not help you being able to go above 5 check if your fuel lines are connected right cause that happened to me once it was corrected wrong and it worked but could not redline

01-15-2009, 08:25 PM	#9
AxiS14 Join Date: Dec 2008 Location: Worcester MA Age: 39 Posts: 19 Trader Rating: (0) Feedback Score: 0 reviews	So its been 3 weeks now still have the same problems. i bought a MAF from a friend that worked and it didnt solve my issues. So 2 days ago at work i lifted the hood and was staring at my engine i decided to sit and listen to the engine while i pulled each injector out....#1 pulled idle dropped.....#2 pulled idle dropped...#3 pulled idle dropped.....#4 pulled...nothin changed... I FOUND IT!!! i took a screwdriver i had and put my ear to the plastic end and put the tip of it on the injector to listen for the pulses....very faintly compared to the other injectors, so i think its dying on me. I have 2 injectors on the way should be here by tuesday. I know this will fix my idle problem and my bogging undera 1/4 tank of gas. But the real question is, will this fix my rev limit?