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Mile High Silvia · 03-19-2014, 08:24 PM

clogged catalytic converter?

zerodameaon · 03-19-2014, 10:10 PM

Quote:

Originally Posted by Livid_240sx

What is?

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That would be spam. If you see stupid posts like that just report them.

mechanicalmoron · 03-21-2014, 05:31 PM

Quote:

Originally Posted by Shadow_S14

So a quick update on my gas issue. I'm getting less miles to the gallon now, down to about 13mpg. There aren't any exhaust leaks that I could tell. I sent out my injectors to get cleaned, didn't change much, so that wasn't the issue. Two codes kept popping up. P0325 and P0400 or Knock Sensor and EGR System. I checked the Knock Sensor; it was cracked to shit so I changed it with a new one and checked wiring on harness/sub-harness and all is good with continuity and resistance. But the code still persists... any suggestions on this one? For the EGR I took out the EGR itself cleaned it out, got rid of all the build up inside and replaced hoses. I assembled it all back and noticed that when I push up the diaphragm in the valve it doesn't stall out or change idle speed at all. Although when I rev the car it does lift up as it should... I'm a little stumbled here, any insight would be great.

Did you torque the knock sensor correctly?

I believe that not only can over-torquing destroy them, but under or over, and they will not read right, and the computer will tell you something's off.

***FaLKoN240*** · 03-21-2014, 05:56 PM

What happened when you changed the CTS? I changed mine and it's made a difference I think...

Shadow_S14 · 03-21-2014, 09:37 PM

Oddly enough, after changing the CTS the knock sensor and EGR codes went away. Now I have codes 12 (MAF?) and 76 (Fuel Inj.). Yes, I torqued the knock sensor to spec. Also my O2 sensor(primary) is dead. I changed it a few months back; is it possible it's dead already? I took it out it's black as f**k!

***FaLKoN240*** · 03-22-2014, 12:02 AM

If it's black that means your car is running rich. Which may be why you're getting crap mileage.

It probably is black from the faulty CTS thinking the car was cold. Corrosion is an insulator (resistor) which will send the wrong voltage to the ECU making it think the engine is cold, putting it in a cold start AF mixture.

I might be wrong but my limited knowledge on how stock cars operate makes me think this.

turbos14 · 03-27-2014, 11:51 PM

Black is rich and if it was bad for awhile it could have ruined your O2 sensor and worse your cat. Are you getting any codes currently and what are they?

Kingtal0n · 03-28-2014, 05:19 PM

I am putting down a legit 25mpg automatic stock KA24DE 97 driving spirited around town.
IF I drive it easy around town I can top 27mpg.

Highway is about 30~mpg, below 74mph. At 82mph I only get about 25-26 mpg.

Method used:
Top off tank, drive X miles, Top off tank, divide mileage/gallons. Done this repeatedly since I owned the car for precision.

Shadow_S14 · 03-29-2014, 09:45 PM

27? Holy shit! Well the CEL turned off and I'm not getting any codes; only 55 which is all good. Is it weird that everything seemed to fix itself after changing the Temp Sensor? I'm still not getting results...

solo_ryder · 03-29-2014, 09:58 PM

My average on a healthy 96 ka 5 speed mixed is 8.6l/100km which equates to 27.35 mpg. Thats 60/40 highway/city with me driving it normal with some WOT runs. All I had at the time of those recordings was a 3" catback. Everything else 100% stock 87 octane. Double check your timing and look for exhaust leaks.

CTS as others said will cause the car to run rich if it cant read temps. Make sure your air filter is clean, fuel filter is clean etc.

turbos14 · 03-29-2014, 10:49 PM

Too bad you don't have a scan tool to look at your vehicle data. Like short and long term fuel trims which shows if you are running rich and by how much, plus able to see o2 readings and such. How are you checking your codes?

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Shadow_S14 · 03-29-2014, 11:17 PM

I was using a Diagnostics Scan Tool and have also been checking the codes directly through the back of the ECU.

turbos14 · 03-29-2014, 11:46 PM

If no codes and you have plenty of miles since last clear then nothing is too far out of specs. I would then check and make sure everything is tip top. Like timing, throttle body intake air control and intake are clean along with maf, idle good, and a compression and leak done test for internal health.

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Zzz89 · 04-05-2014, 11:35 PM

Also try spraying your MAF with CRC MAF cleaner. I had a dirty MAF which threw a leaky injector code and caused the car to run rich.

03-21-2014, 05:56 PM	#34
*FaLKoN240* Super Moderator Join Date: Jun 2004 Location: SF Bay Area Posts: 16,760 Trader Rating: (73) Feedback Score: 73 reviews	What happened when you changed the CTS? I changed mine and it's made a difference I think... __________________ Best way to do business with me? Make your best offer FIRST.

03-21-2014, 09:37 PM	#35
Shadow_S14 Leaky Injector Join Date: Nov 2012 Location: Bay Area, CA Posts: 57 Trader Rating: (4) Feedback Score: 4 reviews	Oddly enough, after changing the CTS the knock sensor and EGR codes went away. Now I have codes 12 (MAF?) and 76 (Fuel Inj.). Yes, I torqued the knock sensor to spec. Also my O2 sensor(primary) is dead. I changed it a few months back; is it possible it's dead already? I took it out it's black as f**k! __________________

03-22-2014, 12:02 AM	#36
*FaLKoN240* Super Moderator Join Date: Jun 2004 Location: SF Bay Area Posts: 16,760 Trader Rating: (73) Feedback Score: 73 reviews	If it's black that means your car is running rich. Which may be why you're getting crap mileage. It probably is black from the faulty CTS thinking the car was cold. Corrosion is an insulator (resistor) which will send the wrong voltage to the ECU making it think the engine is cold, putting it in a cold start AF mixture. I might be wrong but my limited knowledge on how stock cars operate makes me think this. __________________ Best way to do business with me? Make your best offer FIRST.

03-28-2014, 05:19 PM	#38
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 38 Posts: 4,646 Trader Rating: (17) Feedback Score: 17 reviews	I am putting down a legit 25mpg automatic stock KA24DE 97 driving spirited around town. IF I drive it easy around town I can top 27mpg. Highway is about 30~mpg, below 74mph. At 82mph I only get about 25-26 mpg. Method used: Top off tank, drive X miles, Top off tank, divide mileage/gallons. Done this repeatedly since I owned the car for precision. __________________ 5.3/4l80e/turbo 240sx playthrough: https://tinyurl.com/turbo240

03-29-2014, 09:45 PM	#39
Shadow_S14 Leaky Injector Join Date: Nov 2012 Location: Bay Area, CA Posts: 57 Trader Rating: (4) Feedback Score: 4 reviews	27? Holy shit! Well the CEL turned off and I'm not getting any codes; only 55 which is all good. Is it weird that everything seemed to fix itself after changing the Temp Sensor? I'm still not getting results... __________________

03-19-2014, 08:24 PM	#31
Mile High Silvia Leaky Injector Join Date: Jun 2013 Location: nor co Posts: 137 Trader Rating: (0) Feedback Score: 0 reviews	clogged catalytic converter?

03-27-2014, 11:51 PM	#37
turbos14 Leaky Injector Join Date: Jun 2010 Location: OR Posts: 146 Trader Rating: (2) Feedback Score: 2 reviews	Black is rich and if it was bad for awhile it could have ruined your O2 sensor and worse your cat. Are you getting any codes currently and what are they?

03-29-2014, 09:58 PM	#40
solo_ryder Zilvia Junkie Join Date: Mar 2011 Location: The True North Posts: 529 Trader Rating: (18) Feedback Score: 18 reviews	My average on a healthy 96 ka 5 speed mixed is 8.6l/100km which equates to 27.35 mpg. Thats 60/40 highway/city with me driving it normal with some WOT runs. All I had at the time of those recordings was a 3" catback. Everything else 100% stock 87 octane. Double check your timing and look for exhaust leaks. CTS as others said will cause the car to run rich if it cant read temps. Make sure your air filter is clean, fuel filter is clean etc.

03-29-2014, 10:49 PM	#41
turbos14 Leaky Injector Join Date: Jun 2010 Location: OR Posts: 146 Trader Rating: (2) Feedback Score: 2 reviews	Too bad you don't have a scan tool to look at your vehicle data. Like short and long term fuel trims which shows if you are running rich and by how much, plus able to see o2 readings and such. How are you checking your codes? Sent from my SGH-I747 using Tapatalk

03-29-2014, 11:17 PM	#42
Shadow_S14 Leaky Injector Join Date: Nov 2012 Location: Bay Area, CA Posts: 57 Trader Rating: (4) Feedback Score: 4 reviews	I was using a Diagnostics Scan Tool and have also been checking the codes directly through the back of the ECU. __________________

03-29-2014, 11:46 PM	#43
turbos14 Leaky Injector Join Date: Jun 2010 Location: OR Posts: 146 Trader Rating: (2) Feedback Score: 2 reviews	If no codes and you have plenty of miles since last clear then nothing is too far out of specs. I would then check and make sure everything is tip top. Like timing, throttle body intake air control and intake are clean along with maf, idle good, and a compression and leak done test for internal health. Sent from my SGH-I747 using Tapatalk

04-05-2014, 11:35 PM	#44
Zzz89 Leaky Injector Join Date: Apr 2011 Location: CenCal Posts: 129 Trader Rating: (4) Feedback Score: 4 reviews	Also try spraying your MAF with CRC MAF cleaner. I had a dirty MAF which threw a leaky injector code and caused the car to run rich.

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