why won't my check engine light come on? and useless harnesses?

[NissaNassin1031]

90 240sx coupe, original motor. i tried searching. I failed smog today (high nox at 15mph)but am sure I can pass with a few tricks but my engine light doesn't ever come on. he checked it by turning key to on position and it never lights up. It should be on because my ECU threw a code 13(btw what exactlyt is that 1?) and I know I have stuff disconnected that would prob make it come on. I went through the PITA to get to the back of it and managed to pull out the light bulb and it looked perfectly fine and nothing was loose so gas light comes on when low, not sure about that wiper one, never needed it to so im not sure if it works.

There was also 2 harnesses I found near fuse panel towards hood release that plug into somethin but I didn't see anywhere for them to go. I have a base model but someone (dealer?) added A/C (I removed) and sunroof(thats broke/leaks). One of previous owner wired in switch for fog lights and maybe messed with somethin? one was the one hooked to the door chime thing which i disconnected myself. the other was wrapped up with a bundle of other wires and couldn't tell where it led.

thanks for the input guys. I have til mid september to fix this but sometimes it'd be nice to know if my engine is mad at me and wants to throw a code.

[89twoforty]

code 13 is "Engine temperature sensor circuit".

Check out zerothread?id=254375

It's for DOHC but testing should be the same.

As for your CEL coming on, even if the bulb looks good it wouldn't hurt to try changing it.

If you can get some pictures of the harness(es) you're talking about it might help us tell you what they're for.

[NissaNassin1031]

thanks for the link, thats whats making my engine run so rich and waste so much gas...damn. I just didn't really care cuz I knew my temp gauge worked and it didn't seem like engine got too hot... but ECU thinks it is.well changing the bulb woulda been smart. im guessing the one from the wiper thing or gas light would have worked huh? F*** i just put it all back together. ha, as for the plugs i have one of the bigger one that is wrapped with the door chime thing, the other was a lil above and is about the same but more of a square than rectangle. Anyone know if Nissan just left harnesses on the s13's without all the options cuz it'd be easier?sorry for bad quality cell phone pic i moved and snaped it just thinkin maybe id ask online later if anyone knew about it. EDIT: just realized one of harnesses is probably for a footlight. the 240 is supposed to have one right? cuz theres a hole i didnt know what it was for and thats about length plug reached to but i guess the guy just took it out. so now I gotta figure out that other one.

BTW my sensor was corroded and i cleaned it and now my car ran so much better and wasn't popping like it usually does. it was dumping in too much fuel. All I had to do was listen to my ecu about that code and I fixed the problem. :] oh yeah and I had a big vacuum leak before throttle body that duck tape fixed

Modified by NissaNassin1031 at 9:13 PM 8/20/2008
Modified by NissaNassin1031 at 9:19 PM 8/20/2008

[89twoforty]

Glad you got the sensor fixed. As for the mystery plugs, I'm not really sure.

I'll take a look when I go out to my car next. Hopefully someone can help you out on that one.