CEL Light on 96 HELP !

[red_nsxt]

Hi guys

I am new to prime , and i just purchased my 2nd NSX( Red 96) about 2 months ago. Right away I started modding the car . Unfortunately this is the first time doing H/E/I on my car. I did some research on prime cuz i knew it was an odd ball year for the exhaust ( where as my 92 was already equipped !) I purchased a GT one v5.1,test pipes, and OBX Headers ( I know someone will cut me down for buying those ! LOL) The OBX only have the one O2 bung so my mechanic put the primary from Bank 1 in the test pipes about 8" in front of the secondary. The CEL comes on right at I fire her up with TCS.

1 Is the bung in the wrong place ?, should it be located in one leg or pipe from the header before the collector ?

BTW scan code shows primary 1 bank 1 heater sensor .

I also replaced 02 sensors

Thanks for the help in advance guys !

 

[EdinKali]

Shouldn't the primary 02 sensor be in front of the secondary sensor since it measures the difference in emissions before and after the cats?

 

[red_nsxt]

Sorry about that , but ya it is 8" in front of the secondary

 

[Larry Bastanza]

mmm... You say you have test pipes. This will surely set the CEL on. They test the cat which you removed. The system is not like the 1992, it is OBDII and checks the cats. That is why you have four 02 sensors vs. your 1992 that had two.

To resolve this you need to mod the mounting of the secondary 02 sensors. To get how to do it go here:

http://www.energeticforum.com/renew...odification-using-spark-plug-non-foulers.html

BTW, forget the TCS light, just fix above and all will be fine.

HTH,
LarryB

 

[red_nsxt]

mmm... You say you have test pipes. This will surely set the CEL on. They test the cat which you removed. The system is not like the 1992, it is OBDII and checks the cats. That is why you have four 02 sensors vs. your 1992 that had two.

To resolve this you need to mod the mounting of the secondary 02 sensors. To get how to do it go here:

http://www.energeticforum.com/renew...odification-using-spark-plug-non-foulers.html

BTW, forget the TCS light, just fix above and all will be fine.

HTH,
LarryB

I forgot to mention that I have the anti foulers on the secondarys already . They came with 3 orfus and I am using the most restrictive one , all seems to be well with secondarys according to scan tool .

Any other thoughts Larry ?

This is driving me nuts!

 

[red_nsxt]

I don't know if this has anything to do with the problem but , my GT one v5.1 came off a 97-99 , my headers are 91-94 so the usual 95-96 exhaust adapters that are needed (with the curves ) were eliminated because the 97 exhaust has the bend in them already, but the kicker is the testpipes for 95-96 didn't fit, and my mechanic had to cut the bank one test pipe to fit this all together !.According to him they are "extremely tight fitment " The exhaust note on the car seems like it is "binding ".and makes a loud ticking sound on deaccleration usually, or if I hold it steady at 30000 rpm in 2nd gear . When I drive on the highway it seems to be fine . I don't know if this is related or not to the CEL issue, just trying to give you guys as much info as I can.I will try to post some pics when I get the chance .:

 

[Larry Bastanza]

OK Bank 1 Heater is the rear primary(before cat) so if the sensor is new, I suspect you have some bad wiring harness connection.

The "heater" is just like a bulb fitament. It is telling you the heater is "open". Time to review the wiring, with the service manual and check the continuity for the sensor heater. The harnesses can get the male pins pushed in, making no contact.

Regards,
LarryB

 

[red_nsxt]

OK Bank 1 Heater is the rear primary(before cat) so if the sensor is new, I suspect you have some bad wiring harness connection.

The "heater" is just like a bulb fitament. It is telling you the heater is "open". Time to review the wiring, with the service manual and check the continuity for the sensor heater. The harnesses can get the male pins pushed in, making no contact.

Regards,
LarryB

Thanks for the reply again Larry , I will check the pins on the harness, actually i had to by the extension harness from SOS , so I'll check the OEM harness for continuity and a visible inspection when i get a chance . Would any of the above that I just mentioned have anything to do with it ?

 

[Larry Bastanza]

Would any of the above that I just mentioned have anything to do with it ?

I really doubt it. Your failure is a hard failure of a simple curcuit. Anything related to fitment/leaks/blockage would not give you that code, but maybe a few others.

Regards,
LarryB

 

[lithiumus]

Instead of messing around with the test pipes, why don't you consider a set of hiflow cats? Of course with your frankenstein header/exhaust combo you'll likely need to customize the cats to fit.

You'll get the same flow as test pipes and the O2 sensors will see a cat and should not set off CELs. The sound is almost if not as loud as test pipes.

I see why your mechanic is saying it's a tight fit since the 91-94 headers are longer and the 95+ exhaust pipes are also slightly longer. Not sure how much room you have for cats... any pics?

 

[red_nsxt]

Instead of messing around with the test pipes, why don't you consider a set of hiflow cats? Of course with your frankenstein header/exhaust combo you'll likely need to customize the cats to fit.

You'll get the same flow as test pipes and the O2 sensors will see a cat and should not set off CELs. The sound is almost if not as loud as test pipes.

I see why your mechanic is saying it's a tight fit since the 91-94 headers are longer and the 95+ exhaust pipes are also slightly longer. Not sure how much room you have for cats... any pics?

Actually the bank one testpipe he had to cut off about 3-5" and reweld . Frankenstein is right ! LOL , see i wasn't aware at the time that 97-99 exhaust had the exhaust adapters incorporated , when I got the exhaust I was Like "YES, this is awesome " I just saved 200$, but the kicker is there not 97-99 headers so ya,testpipes have a serious Frankenstein going on.and to boot I would have to modify my cats, I don't even think they will fit with this setup, One will the other won't, I will post some pics soon.