B18CR O2 Sensor Check light. WONT GO AWAY

**hondavti25** · 13-07-2011 10:29 PM

Hi Guys,

My engine check light popped on the other day randomly after driving for about 20 mins. When I got home I took it for another spin and nothing, but the next day same thing. Since then it just comes on after about 20 mins of driving. Took the car to the mechanic and his replaced the O2 sensor but we are still getting the same issue. Have been told this shouldn't be problem and I may need to put an aftermarket computer in if I want to get rid of the error.

Any body else had this problem or any thoughts on what else to try be awesome!

Car is a EJ8 with a B18CR in it. Only mods are a carbon big tube intake and cat back.

Thanks,

**B18cEG** · 15-07-2011 12:47 AM

have you tried to reset the ecu my disconnecting it for a few minutes? no doubt you have but just checking

**90LAN** · 15-07-2011 11:22 AM

check the code of the cel and fix what ever it is

**hondavti25** · 17-07-2011 12:19 AM

Yeah I have reset the ecu and so has the mechanic by the looks of things. 90LAN check light was apparently the O2 sensor and that had been replaced?

**ECU-MAN** · 20-07-2011 05:06 PM

you really should check the code in the ECU when the problem happens again

did you put in a new O2
was the old O2 tested
was the wiring tested

just because the ECU says its your O2 ( code 1 ) dosnt mean it is. could be a wiring issue.

**DC2-PWR** · 20-07-2011 06:41 PM

Originally Posted by hondavti25

Yeah I have reset the ecu and so has the mechanic by the looks of things. 90LAN check light was apparently the O2 sensor and that had been replaced?

I had a simular issue and it was one of the wires that was loose, where the o2 sensor wire connects. Check for connection if any wires are popping out.

**hondavti25** · 23-07-2011 06:33 PM

From what I know it was O2 sensor was replaced and when the code came back they troubleshot. I'll have a look my self but the loose wire theory is looking good.

**VT3C** · 26-07-2011 04:48 PM

Originally Posted by hondavti25

Have been told this shouldn't be problem and I may need to put an aftermarket computer in if I want to get rid of the error.

i'd be looing for a new mechanic also if he's taking the old 'just chip it out' approach by reccomending an aftermarket ECU to 'solve' the problem HaHAHA.

I assume it was running fine at some stage since doing your swap ? with no codes that means.. otherwise it's more than likely a JDM versus AUS spec O2 sensor wiring issue.

**Banana_hammock** · 28-07-2011 10:27 PM

I'm leaning towards the possible dodgey job done by the mechanic. Use a proper scanning tool like the Actron Scantool and AutoXray to check your error code (with the Haynes manual). Once you've confirmed yourself that it's the O2 sensor, then the only thing left to do is check the wiring paths from the sensor itself.

And there's also the possibility that your mechanic actually didn't do a good job changing (if he did change it).

**hondavti25** · 28-07-2011 10:50 PM

Thanks guys, as for dodgy mechanic I think his good for installing and has a good name to be honest in hondas. I'll take a closer look when I install my headers. So pretty much I am looking at the wiring? Also the car has shorted out twice since the B18CR was installed could this be related?

**Banana_hammock** · 28-07-2011 11:11 PM

Something may not be grounded. There would be a lot of wiring to go through though.

**TODA AU** · 29-07-2011 05:15 PM

There are 4 wires that need to be checked.
Why hasn't this been done? Surely this is normal to check before condemning the sensor.
If It's an O2 error, that narrows it down to 2.
Conversely, if it's an O2 heater error it narrows it down to the other 2.
It's not rocket science.