CEL Issue (misfire codes)

[GEENSX]

OK once again my CEL is on my 03. I installed a Taitec GTLW exhuast (used)last week and this is my third day driving and the CEL came on.
I replaced the gasket to the "CONVERTER"

I then got a OBII reading 5 different codes

P0300 random Misfire
P1201 Cylinder 1 Misfire
P1202 Cylinder 2 Misfire
P1203 Cylinder 3 Misfire
P1456 Evaporative Emission Control System Leak Detected (Fuel Tank System) I know this is possible gas cap issue i'm going to replace that for sure

I replaced the my RR Primary 02 sensor about a month ago and the RR secondary last year.

I checked the bolts they're tightly fitted
Is there a gasket that goes between the adatpors and the exhaust? I can't really tell from SOS site.
Can anyone who purchase this new have some insight on installation on a later model 02 +?


When i installed the exhaust with the na2 adapters they didn't fit perfectly.
I had to use some elbow grease to get it to fit then when I installed it the pipes were crocked I had to use some creative thinking and elbow grease to twist and get the pipes in line.

Does anyone know in the later model adapters are different from the early ones?
My next thought is to take it to a muffler shop..

Thanks guys.

 

[GEENSX]

Forgot to added the CEL was blinking at one point twice while I was driving then the TCS light came on too( This was before I took it the advance auto to get the OBDII test). then TCS went away after i start back up.
another thing to mention after i installed the exhuast had some smoke coming from the right exhaust pipe, left had little water coming out the left, i sure thats from when I ran some water through it the day before install( heard something jiggling inside try to flush in out)
I reset it drove about 10 miles to the dealer and picked up a new gas cap.
NO CEL as yet.

 

[BluryNSX]

I would need so much more info, from the info given it is very unlikely the recent mods..I would check the coresponding bank as I believe th 301,302, and 303 are one side.. 300 is just there because of the others. did you clean the engine or anything as well?

I am not sure if running water through a muffler would do anything but then again I never tried something like that. unless the muffler getting hot sent steam back into combustion chamber?? doesn't seam possible to me but I am just throwing out thoughts... maybe to much water got soaked into baffling... hmmm please update this as you dive deeper this is really interesting to me lol.

as much of a pain as it is may try swapping back parts and drive the car for a week and see what happens, if issue clears then something is wrong with muffler, if it doesn't then you know there is something else there. I don't think throwing money at parts in this case is the way to go you have stuff to kinda work you're way through and double check what was recenlt installed for a few hours of work.

good luck

my bad 301,302, 303 would be normal misfires on most hondas... same applies to 1200 series though

 

[GEENSX]

I didn't clean the engine or any other parts haven't driven in any rain recently.
I drove it the same day installed it no issue it sat for about 6 days drove no issue drove it the next morning about 5 miles into the drive stop at a light and drove off normal CEL came on.
When i stop by the dealer yesterday I ask their NSX Tech about it and he ask me if I feel any hesitation or loss of pwr I told him no. He said sometime gas with methnol have shown may cause this (hope i'm not quoting him wrong) he told me to reset the CEL and see what happens. Not that i'm saying this cause this but I did get gas the same day I install the exhaust.
I've clear the codes for now and I'll wait and see if CEL pops back up.
I may try your idea of switching back to the OEM exhaust.. man thats going to be a pain in my ass, I might have to take it to a shop for them to do that.

 

[BluryNSX]

I didn't clean the engine or any other parts haven't driven in any rain recently.
I drove it the same day installed it no issue it sat for about 6 days drove no issue drove it the next morning about 5 miles into the drive stop at a light and drove off normal CEL came on.
When i stop by the dealer yesterday I ask their NSX Tech about it and he ask me if I feel any hesitation or loss of pwr I told him no. He said sometime gas with methnol have shown may cause this (hope i'm not quoting him wrong) he told me to reset the CEL and see what happens. Not that i'm saying this cause this but I did get gas the same day I install the exhaust.
I've clear the codes for now and I'll wait and see if CEL pops back up.
I may try your idea of switching back to the OEM exhaust.. man thats going to be a pain in my ass, I might have to take it to a shop for them to do that.

actually the gas is a good wait and see if there is no loss in power or hesitation. I know I have had customers in the past that have some hicups when the seasons change because of changes in gas. I would consider adding more gas to dilude the old when at about half tank.