$10 if you figure out my emission problem. Different ecus giving different codes. - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

az_240 · 02-02-2010, 05:16 PM

This emissions problem is kicking my ass in every possible way.

I have a 97' 240 w/ 120k that was originally automatic which passed emissions just fine back in the day. It now has a manual transmission and will not pass due to an evap or possible wiring issue.

I was told all I'd need is a 97' manual ECU. Borrowed one from someone and did not pass because of code P0443 (evap emission control system purge control valve circuit) and failed the gas cap test. Got a new aftermarket gas cap and checked the evap canister and lines for charcoal, evap solenoid, evap purge control valve for resistance, purge valve and vac lines. I also checked some other things the FSM says to check and everything seems fine.

I had to give the manual ECU back to the guy so now im using my auto ECU and instead of code P0443 I get code P1445(evap canister purge volume control valve) along with the auto transmission malfunction code.

I decided to just take my car into a shop to have it looked at and explained everything to the mechanic. He looked everything over and could not find anything wrong.

He suggested the wiring might be wrong somehow since I'm getting two different codes with two different ECU's which should not happen.

Also code P1445 comes back IMMEDIATELY after being cleared.
I don't even start the engine and I have code P1445. With the manual ECU I was able to drive about 5 miles before code P0443 showed up.

Why would I get different codes with different ECU's?!?!?!?!

I know people have done manual swaps in their OBDII cars and have not had this issue.

Does anyone make a OBDII check engine light eliminator for our cars? ANY possible way around emissions or info on how to fix my car is greatly appreciated.

If you find a reasonable solution for passing emissions I will send you $10 through paypal or money order... whichever you prefer.

SR240DET · 02-02-2010, 05:57 PM

what year is your manual ecu? Actually, just post the manufacturer pin number on the ECU.

az_240 · 02-02-2010, 06:41 PM

The guy says it's from a 97' manual. I could not find the code listed online but it's definitely a manual since it does not throw a tranny code in my car.

Code is A18-J05 GA6

smbonn2005 · 02-02-2010, 07:24 PM

You either have a vacuum line disconnected or the evap purge valve went bad is what i think. Each ECU was using a different code for pretty much the same problem.

az_240 · 02-02-2010, 09:29 PM

How can an ECU detect a vac leak if the engine is not running? I get the P1445 code immediately after clearing them. That rules out vac leaks.

I checked resistance on the evap purge valve. 19.2 ohms. FSM calls for apprx. 30.
It's a little low but everyone I talked to says the valve should be fine.

If the purge control valve really was bad I should get the same code with BOTH ECU's.

I would just replace it but it is under the intake manifold which makes it a bitch to change and the valve itself is expensive.

smbonn2005 · 02-02-2010, 09:37 PM

Either way you need to pull it to test it or replace it. And being 10.8ohms under the resistance spec I would say it is definitely no good.

Remove EVAP canister purge volume control valve from intake manifold collector and disconnect hoses from the valve. (Plug the purge hoses. The EVAP canister purge volume control valve harness connector should remain connected.)

Turn the ignition switch "ON" and "OFF". Check that the EVAP canister purge volume control valve shaft moves smoothly forward and backward according to the ignition switch position. If no good, you need to replace the EVAP canister purge volume control valve.

az_240 · 02-02-2010, 09:54 PM

No way im going to remove the intake manifold to test a valve that is probably fine.

I have a feeling if it really was bad I'd be getting P1445 on the manual ecu as well.

smbonn2005 · 02-02-2010, 09:55 PM

Then dont do it right, thats how you are supposed to test it.

az_240 · 02-03-2010, 02:42 AM

The possibility that this valve is bad is unlikely.
I'm going to try some other things out before I do something that intense.

I'd want to kill small animals if I tore everything apart only to find that it works fine.

Any helpful info?

240sxChillen · 02-03-2010, 02:59 AM

ObII is the biggest bitch ever. I have a CEL cause of a speed Sensor and cant pass smog cause of it.Hope you get it fixed/Smogged, i know how stressful this shit is.

smoothcoupe · 02-03-2010, 03:22 AM

uhhh... pretty easy actually. take gauge cluster out(takes 20 minutes) then but a paper gasket o ring in between the check engine valve so that they DON'T make contact, then solder two wires to the oil pressure light.....DONE. when key is in ignition, light will turn on, when car is on, light will come off like oil pressure light. This is of course assuming you pass the smog portion of the test as well.

az_240 · 02-03-2010, 03:51 AM

^This is not an OBDI car.

OBDII is tested with an obd code reader.
They don't actually test for smog.

smbonn2005 · 02-03-2010, 11:29 AM

Well with the resistance being that low it would set a check engine light because the ECU is getting a higher voltage back as a signal than it is supposed to. That makes the ECU think that the valve is in a different position than it is commanded to be.

*DALAZ_68* · 02-03-2010, 12:07 PM

give me ur car...problem solved...

az_240 · 02-03-2010, 06:57 PM

Quote:

Originally Posted by smbonn2005

Well with the resistance being that low it would set a check engine light because the ECU is getting a higher voltage back as a signal than it is supposed to. That makes the ECU think that the valve is in a different position than it is commanded to be.

I asked nissan techs about this a week ago and was told it's doubtful since it would trigger the same code for the manual ecu as well.

I found a guy who says he guarantees I will pass for $150... no payment until it passes.

After being rejected for a waiver and the VVR&R program I'd rather find a way around not fixing it.... fuck whoever came up with these emissions regulations and the useless programs that are designed to help people pass. I know mine is emission related but people should not fail due to non emission related problems.

02-02-2010, 05:16 PM	#1
az_240 Post Whore! Join Date: Jan 2006 Location: Phx Posts: 3,097 Trader Rating: (41) Feedback Score: 41 reviews	$10 if you figure out my emission problem. Different ecus giving different codes. This emissions problem is kicking my ass in every possible way. I have a 97' 240 w/ 120k that was originally automatic which passed emissions just fine back in the day. It now has a manual transmission and will not pass due to an evap or possible wiring issue. I was told all I'd need is a 97' manual ECU. Borrowed one from someone and did not pass because of code P0443 (evap emission control system purge control valve circuit) and failed the gas cap test. Got a new aftermarket gas cap and checked the evap canister and lines for charcoal, evap solenoid, evap purge control valve for resistance, purge valve and vac lines. I also checked some other things the FSM says to check and everything seems fine. I had to give the manual ECU back to the guy so now im using my auto ECU and instead of code P0443 I get code P1445(evap canister purge volume control valve) along with the auto transmission malfunction code. I decided to just take my car into a shop to have it looked at and explained everything to the mechanic. He looked everything over and could not find anything wrong. He suggested the wiring might be wrong somehow since I'm getting two different codes with two different ECU's which should not happen. Also code P1445 comes back IMMEDIATELY after being cleared. I don't even start the engine and I have code P1445. With the manual ECU I was able to drive about 5 miles before code P0443 showed up. Why would I get different codes with different ECU's?!?!?!?! I know people have done manual swaps in their OBDII cars and have not had this issue. Does anyone make a OBDII check engine light eliminator for our cars? ANY possible way around emissions or info on how to fix my car is greatly appreciated. If you find a reasonable solution for passing emissions I will send you $10 through paypal or money order... whichever you prefer.

02-02-2010, 09:29 PM	#5
az_240 Post Whore! Join Date: Jan 2006 Location: Phx Posts: 3,097 Trader Rating: (41) Feedback Score: 41 reviews	How can an ECU detect a vac leak if the engine is not running? I get the P1445 code immediately after clearing them. That rules out vac leaks. I checked resistance on the evap purge valve. 19.2 ohms. FSM calls for apprx. 30. It's a little low but everyone I talked to says the valve should be fine. If the purge control valve really was bad I should get the same code with BOTH ECU's. I would just replace it but it is under the intake manifold which makes it a bitch to change and the valve itself is expensive. Last edited by az_240; 02-03-2010 at 03:53 AM..

02-03-2010, 12:07 PM	#14
DALAZ_68 not giving a fuck Join Date: Apr 2007 Location: Los angeles Age: 37 Posts: 15,077 Trader Rating: (104) Feedback Score: 104 reviews	give me ur car...problem solved... __________________ LOL 240... whats better than 1? 5 1's ...lol PSN & XBL GT : Wh0pp3r68 CLUB LEXUS : Wh0pp3r

02-02-2010, 05:57 PM	#2
SR240DET Zilvia FREAK! Join Date: Mar 2002 Location: orida Posts: 1,490 Trader Rating: (0) Feedback Score: 0 reviews	what year is your manual ecu? Actually, just post the manufacturer pin number on the ECU.

02-02-2010, 06:41 PM	#3
az_240 Post Whore! Join Date: Jan 2006 Location: Phx Posts: 3,097 Trader Rating: (41) Feedback Score: 41 reviews	The guy says it's from a 97' manual. I could not find the code listed online but it's definitely a manual since it does not throw a tranny code in my car. Code is A18-J05 GA6

02-02-2010, 07:24 PM	#4
smbonn2005 Zilvia Junkie Join Date: Sep 2009 Location: Bellingham, MA Age: 33 Posts: 315 Trader Rating: (9) Feedback Score: 9 reviews	You either have a vacuum line disconnected or the evap purge valve went bad is what i think. Each ECU was using a different code for pretty much the same problem.

02-02-2010, 09:37 PM	#6
smbonn2005 Zilvia Junkie Join Date: Sep 2009 Location: Bellingham, MA Age: 33 Posts: 315 Trader Rating: (9) Feedback Score: 9 reviews	Either way you need to pull it to test it or replace it. And being 10.8ohms under the resistance spec I would say it is definitely no good. Remove EVAP canister purge volume control valve from intake manifold collector and disconnect hoses from the valve. (Plug the purge hoses. The EVAP canister purge volume control valve harness connector should remain connected.) Turn the ignition switch "ON" and "OFF". Check that the EVAP canister purge volume control valve shaft moves smoothly forward and backward according to the ignition switch position. If no good, you need to replace the EVAP canister purge volume control valve.

02-02-2010, 09:54 PM	#7
az_240 Post Whore! Join Date: Jan 2006 Location: Phx Posts: 3,097 Trader Rating: (41) Feedback Score: 41 reviews	No way im going to remove the intake manifold to test a valve that is probably fine. I have a feeling if it really was bad I'd be getting P1445 on the manual ecu as well.

02-02-2010, 09:55 PM	#8
smbonn2005 Zilvia Junkie Join Date: Sep 2009 Location: Bellingham, MA Age: 33 Posts: 315 Trader Rating: (9) Feedback Score: 9 reviews	Then dont do it right, thats how you are supposed to test it.

02-03-2010, 02:42 AM	#9
az_240 Post Whore! Join Date: Jan 2006 Location: Phx Posts: 3,097 Trader Rating: (41) Feedback Score: 41 reviews	The possibility that this valve is bad is unlikely. I'm going to try some other things out before I do something that intense. I'd want to kill small animals if I tore everything apart only to find that it works fine. Any helpful info?

02-03-2010, 02:59 AM	#10
240sxChillen Zilvia Junkie Join Date: Aug 2009 Location: Norcal. Posts: 390 Trader Rating: (14) Feedback Score: 14 reviews	ObII is the biggest bitch ever. I have a CEL cause of a speed Sensor and cant pass smog cause of it.Hope you get it fixed/Smogged, i know how stressful this shit is.

02-03-2010, 03:22 AM	#11
smoothcoupe BANNED Join Date: Feb 2010 Location: Santa Ana Posts: 9 Trader Rating: (0) Feedback Score: 0 reviews	uhhh... pretty easy actually. take gauge cluster out(takes 20 minutes) then but a paper gasket o ring in between the check engine valve so that they DON'T make contact, then solder two wires to the oil pressure light.....DONE. when key is in ignition, light will turn on, when car is on, light will come off like oil pressure light. This is of course assuming you pass the smog portion of the test as well.

02-03-2010, 03:51 AM	#12
az_240 Post Whore! Join Date: Jan 2006 Location: Phx Posts: 3,097 Trader Rating: (41) Feedback Score: 41 reviews	^This is not an OBDI car. OBDII is tested with an obd code reader. They don't actually test for smog.

02-03-2010, 11:29 AM	#13
smbonn2005 Zilvia Junkie Join Date: Sep 2009 Location: Bellingham, MA Age: 33 Posts: 315 Trader Rating: (9) Feedback Score: 9 reviews	Well with the resistance being that low it would set a check engine light because the ECU is getting a higher voltage back as a signal than it is supposed to. That makes the ECU think that the valve is in a different position than it is commanded to be.