Help CEL on and ECU throwing code 45 - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

DanDriftS13 · 01-31-2010, 09:34 AM

The car is a S13 hatch with a stock KA24DE in it. Ever since i got this car about 4 months ago it hasnt ran completely right. When i first got it it wouldn't pull smooth through the rpm range and would give a bit of trouble starting when it was hot out after the motor has been warmed up. Now the problem has gotten worse and the car bogs out and misfires if I push the throttle more than about 25%. Still gives the same problem when starting when its hot out and the motor is warmed up.

So here is what I've done so far.
I check the ecu for codes and got 34 (knock sensor), 43 (tps), and 45 (leaky injector).
First things first I had a brand new knock sensor laying around so I went ahead and replaced and the ecu still wasnt reading the knock sensor. So i then checked the wiring and found the ecu wasnt receiving the signal so I bypassed the harness and wired the sensor to the ecu.

Next was the tps I checked the resistance of it and noticed that it wasnt inside the parameters for a good check out so I decided to replace that too. With the new TPS on the car is still acting exactly the same.

Now to the code 45. Everything I can find says that this code is for california cars only (I am in Orlando, Fl). So my question is because my car is throwing this code should I just assume that the car is a california car and go with that as my problem? If so what can I do to diagnose a leaky injector.

The car idles normal, hesitation when throttle is pushed, and bog past 25% throttle. My fiancee also has a s13 hatch with a dual cam in it so I am going to try the injectors off her car and see if it changes anything on mine. But what else can I try if that doesn't change anything?

Sorry for the long post but any help is greatly appreciated.
Thank You
-Daniel

EDIT* Forgot to mention that the CEL only started to come on yesterday. And it is not constantly on. It will come on completely and stay lit sometimes and then when I press that gas harder or let off it goes away for a few seconds and comes back or stays off for a little bit. Other times it will come on and flash fast like its a strobe light almost...

DanDriftS13 · 01-31-2010, 10:22 AM

Just took the car for about a 20 minute drive and now the CEL doesn't come on anymore. So i am equating that problem to the TPS. Please help me

yukon · 01-31-2010, 04:46 PM

You mean the check engine light on dash is coming on displaying code 45. That would be california but if the code 45 is only flashing on ecu than you have non-cali car. Have you adjusted the new tps to .44 volts and reset computer and set idle? substitute anothe maf. you can isolate bad injectors by running on 3 injectors. i guess replace fuel filter.

Rabboni · 01-31-2010, 04:57 PM

If the cel flashes it usually means a misfire. I would try to diagnose the leaking injector. Sometimes getting an injector cleaning done will clear out injectors, but most of the time you have to replace them.

markapple0507 · 06-24-2010, 10:22 PM

hey dan i have a question for you. im struggling along the way along with the same problems with you but I only have yet to try a new knock sensor. hopefully you found out your solution. my question is dealing with the knock sensor harness. you said that the ecu wasn't reading the ks because of the harness

well i was looking at my harness and it only has 1 lead wire coming from the sensor side of the harness where then it is converted to a 2 wire connection at the other end (see pictures). is this normal or is this anything like what you had? on the sensor side connector it has one wire coming out and on the other side it has a plug. not sure if this was factory or one of the previous owner did it. I went to the junkyard to get another harness but it was the same way. My harness has been this way since i got the car and i've never had problems with it. so I'm not sure if i should leave it as is when i get the new ks or wire it myself like i did. also how did you test to see if the ecu was getting a voltage from the ks.

^^ almost looks factory at the same time not.

^^ here is the plug i was talking about

efrain240sx · 06-26-2010, 09:22 PM

^^^ That is normal for the harness to be like that. The KS pin on the ECM is pin 27, check for voltage there.

DanDriftS13 · 06-29-2010, 07:23 AM

Yes your harness isn't modified in anyway there thats the way they came form the factory. The way I checked for voltage on mine was to disconnect the plug on the harness (the one at the front of the motor) and I checked for voltage there as well as checked for voltage at the ecu (the voltage is extremely minimal maybe 1 or 2 volts). When I saw voltage at the plug coming directly from the ks and not at the ecu I knew somewhere in my harness there was a short. Therefore I bypassed the harness and just added two wires running straight to the ecu.

BTW my problem ended up being my fuel pump AND my maf

01-31-2010, 09:34 AM	#1
DanDriftS13 Leaky Injector Join Date: Feb 2008 Location: Orlando, Fl Age: 37 Posts: 91 Trader Rating: (0) Feedback Score: 0 reviews	Help CEL on and ECU throwing code 45 The car is a S13 hatch with a stock KA24DE in it. Ever since i got this car about 4 months ago it hasnt ran completely right. When i first got it it wouldn't pull smooth through the rpm range and would give a bit of trouble starting when it was hot out after the motor has been warmed up. Now the problem has gotten worse and the car bogs out and misfires if I push the throttle more than about 25%. Still gives the same problem when starting when its hot out and the motor is warmed up. So here is what I've done so far. I check the ecu for codes and got 34 (knock sensor), 43 (tps), and 45 (leaky injector). First things first I had a brand new knock sensor laying around so I went ahead and replaced and the ecu still wasnt reading the knock sensor. So i then checked the wiring and found the ecu wasnt receiving the signal so I bypassed the harness and wired the sensor to the ecu. Next was the tps I checked the resistance of it and noticed that it wasnt inside the parameters for a good check out so I decided to replace that too. With the new TPS on the car is still acting exactly the same. Now to the code 45. Everything I can find says that this code is for california cars only (I am in Orlando, Fl). So my question is because my car is throwing this code should I just assume that the car is a california car and go with that as my problem? If so what can I do to diagnose a leaky injector. The car idles normal, hesitation when throttle is pushed, and bog past 25% throttle. My fiancee also has a s13 hatch with a dual cam in it so I am going to try the injectors off her car and see if it changes anything on mine. But what else can I try if that doesn't change anything? Sorry for the long post but any help is greatly appreciated. Thank You -Daniel EDIT* Forgot to mention that the CEL only started to come on yesterday. And it is not constantly on. It will come on completely and stay lit sometimes and then when I press that gas harder or let off it goes away for a few seconds and comes back or stays off for a little bit. Other times it will come on and flash fast like its a strobe light almost...

01-31-2010, 04:57 PM	#4
Rabboni Zilvia Member Join Date: Aug 2009 Location: Fairfield, CA Posts: 230 Trader Rating: (0) Feedback Score: 0 reviews	If the cel flashes it usually means a misfire. I would try to diagnose the leaking injector. Sometimes getting an injector cleaning done will clear out injectors, but most of the time you have to replace them. __________________ Baling Wire-The Duct Tape Of Champions

06-24-2010, 10:22 PM	#5
markapple0507 Zilvia Member Join Date: Jan 2009 Location: El Paso, Tx Age: 35 Posts: 189 Trader Rating: (4) Feedback Score: 4 reviews	hey dan i have a question for you. im struggling along the way along with the same problems with you but I only have yet to try a new knock sensor. hopefully you found out your solution. my question is dealing with the knock sensor harness. you said that the ecu wasn't reading the ks because of the harness well i was looking at my harness and it only has 1 lead wire coming from the sensor side of the harness where then it is converted to a 2 wire connection at the other end (see pictures). is this normal or is this anything like what you had? on the sensor side connector it has one wire coming out and on the other side it has a plug. not sure if this was factory or one of the previous owner did it. I went to the junkyard to get another harness but it was the same way. My harness has been this way since i got the car and i've never had problems with it. so I'm not sure if i should leave it as is when i get the new ks or wire it myself like i did. also how did you test to see if the ecu was getting a voltage from the ks. ^^ almost looks factory at the same time not. ^^ here is the plug i was talking about __________________ bob,syouruncle

01-31-2010, 10:22 AM	#2
DanDriftS13 Leaky Injector Join Date: Feb 2008 Location: Orlando, Fl Age: 37 Posts: 91 Trader Rating: (0) Feedback Score: 0 reviews	Just took the car for about a 20 minute drive and now the CEL doesn't come on anymore. So i am equating that problem to the TPS. Please help me

01-31-2010, 04:46 PM	#3
yukon Zilvia Member Join Date: May 2009 Location: boston Age: 35 Posts: 157 Trader Rating: (0) Feedback Score: 0 reviews	You mean the check engine light on dash is coming on displaying code 45. That would be california but if the code 45 is only flashing on ecu than you have non-cali car. Have you adjusted the new tps to .44 volts and reset computer and set idle? substitute anothe maf. you can isolate bad injectors by running on 3 injectors. i guess replace fuel filter.

06-26-2010, 09:22 PM	#6
efrain240sx Leaky Injector Join Date: Mar 2006 Location: azusa ca Posts: 127 Trader Rating: (0) Feedback Score: 0 reviews	^^^ That is normal for the harness to be like that. The KS pin on the ECM is pin 27, check for voltage there.

06-29-2010, 07:23 AM	#7
DanDriftS13 Leaky Injector Join Date: Feb 2008 Location: Orlando, Fl Age: 37 Posts: 91 Trader Rating: (0) Feedback Score: 0 reviews	Yes your harness isn't modified in anyway there thats the way they came form the factory. The way I checked for voltage on mine was to disconnect the plug on the harness (the one at the front of the motor) and I checked for voltage there as well as checked for voltage at the ecu (the voltage is extremely minimal maybe 1 or 2 volts). When I saw voltage at the plug coming directly from the ks and not at the ecu I knew somewhere in my harness there was a short. Therefore I bypassed the harness and just added two wires running straight to the ecu. BTW my problem ended up being my fuel pump AND my maf