pride header install, Check engine light!

[Creasian21]

91 , car was running fine before the header install. After i installed the headers, i went on a road test. About 5 mile in it pops up a check engine light. No biggy. I turned the car off/on and the check engine light is off. Drive it about 5 miles, pops back on again. Checked the extension wires, ok. checked the o2 sensor, ok. i thought it would be lean a little bit so i jumped the fuel pump resister box, still pops up a code. i uploaded a video to see if anyone can double check the codes for me. i think i might of read the code wrong, but would like a 2nd opinion. thanks for the help.
https://www.youtube.com/watch?v=Iz9G3LLvoI4&t=19s

 

[Big McLargeHuge]

I see two MIL codes, 36 and 44. 36 is some non-specific "TCFC (traction control fuel cut) signal" and 44 is for "rear fuel supply system".

Based on this old post #4 by LarryB (http://www.nsxprime.com/forum/showt...ror-code-43-44-after-header-install-any-ideas) you might have swapped the front & rear O2 sensor wires. Easy to do since the Pride headers relocate your front O2 sensor back behind the oil pan, so make sure you're routing the rear sensor wire to the rear connector on the rear valve cover and the front sensor wire to the front cover. Make sure that the wires are far from heat and friction.

Other issue might be some penetrating fluid or grease got on the new sensors during install and messed them up. I guess you could take them out to check & clean them, but if that's the issue then you might have to replace them entirely if cleaning doesn't work. Could run without the sensors connected to see if you run better (though you will have permanent codes 41/42 until they're reconnected).

Finally, might not be O2 sensors at all, you could try testing the coil packs, cleaning injectors, checking spark plugs, weak fuel pump, those kinds of fuel/spark-related components but since this popped up right after the header swap I would lean towards the O2's first. Some other threads here (http://www.nsxprime.com/forum/showthread.php/112616-Code-44-on-my-1991-NSX) and here (http://www.nsxprime.com/forum/showt...th-error-code-44-Bad-O2?p=2009071#post2009071). Seems to have multiple possible causes.

Code 36 seems to point to a failing or intermittent wheel speed sensor or bad connection between the ECU & TCS computers, this (http://www.nsxcb.co.uk/showthread.php?14188-ABS-and-TCS-lights-on) might help diagnose. If you clear the codes and it doesn't come back then you might be able to put off potential repairs. If you've disconnected the TCS unit permanently it might just be stored in memory without illuminating the MIL. If you ever get ABS lights then you have more evidence for a wheel speed sensor issue.

 

[asylum]

95% chances that your problem has something to do with the header change. Hence I would check the 02 sensors. Especialy the rear bank one. They are fragile. Check the wiring and if everything is ok, change it (both). They are not expensive.

 

[Creasian21]

thanks for the respond and tips. I disconnected the tcs unit permanently. car is a 91, but I'm using 97+ headers because the ball joint type gasket since I will be running the the angus turbo kit later on. I don't think headers should matter since the o2 is pre cat wit the 91. I did test out the o2 sensor heating wiring and came out in specs. I did switch the o2 sensors back and fourth a couple times, but still code pops up after 5 mile or so. i might just get new o2 sensors since these are like almost 30yrs old. would anyone recommend advancing timing a little bit with complete pride headers/cats/exhaust?

 

[Big McLargeHuge]

I disconnected the tcs unit permanently.

In that case the code should be stored without triggering the engine light so I assume this code can be safely ignored.

car is a 91, but I'm using 97+ headers because the ball joint type gasket since I will be running the the angus turbo kit later on. I don't think headers should matter since the o2 is pre cat wit the 91. I did test out the o2 sensor heating wiring and came out in specs. I did switch the o2 sensors back and fourth a couple times, but still code pops up after 5 mile or so. i might just get new o2 sensors since these are like almost 30yrs old.

So you have the Pride on or the 97+? Either way make sure the connectors aren't mixed up front to back too.
I'm confused on your ball joint logic, I think both Pride V1 and V2 headers use those types of joints. Unless you mean you don't want the donut gasket for exh. gas pressure reasons.
Yes, it would be good to replace them anyways especially if you're doing major engine mods soon, mine were failing occasionally at that age. Less than $100 for the OEM NGKs or Denso which is what I used. Or go wideband or whatever right now and save some work later on.

would anyone recommend advancing timing a little bit with complete pride headers/cats/exhaust?

Do you have an aftermarket ECU or adjustable cams to do that with? I personally would not bother until you do some comprehensive professional tuning with the future turbo kit. Seems like a lot of trouble that most people avoid if you just have exhaust/intake mods that the stock tuning & ignition timing control handles just fine.

 

[Creasian21]

I do have a aem ecu that's plug n play for the 91 nsx, but im running the oem ecu. hopefully this check engine light goes away.

 

[Creasian21]

I was able to get 2 new o2 sensors. denso brand new for $40 off offer up. The o2 sensor was off a 95 honda accord v6. one of them was 234-4065 , 234-4601. The 234-4601 had a female plug end,so i had to re-pin it. I inspected the old o2 sensors again, and one of the o2 sensors had a broken element inside, you can hear it rattling inside when shaking it. reset the clock fuse, test drove it for awhile, no check engine light. So far so good. I also upgraded the fuel injectors to osidetiger 330cc 12 hole injector that was from a toyota, runs great so far, and also adjusted my timing a bit advance a couple degrees. While i was in the engine compartment, my eyes caught a lil tiny bubble from my sos aluminum coolant tank from the top seam. WTF! not even had it for one yr. Hopefully SoS can do something about this.

 

[El-Cojonico]

What's the part number on the injectors? Is it worth it? Do you need adapters and new seals? Thanks

 

[Creasian21]

i got the injector off ebay. search for osidetiger nsx injectors. i only had the car for maybe 1 1/2 yrs, and decided to upgrade the injectors to 12 hole, prolly the same price if you paid to get oem ones clean. Injector kit is plug n plug with 2 size rubber seals to the intake manifold. i left the harden plastic whatever spacer in there and used the thicker rubber seal, and added 2 washers on each fuel rail threads. i think its worth it price wise. i have the full pride system with these injectors and aftermarket clutch. i can feel the car breathing better, revs quicker. fuel milelage seems to be good, i'll get back to you on this one.