FI LTH check engine light
 

I installed my Fast Intensions Long Tube Headers and my check engine light went off. I was very careful on the 02 sensors. Any ideas?

Are you sure you installed the extensions and everything correctly? Give everything one more look, and if you cant find anything give Tony a call he will be more than willing to help you.

When you removed the old pipes. Did you use an air impact on any of the bolts? If you did. Did you remove the O2 sensors before or after using the air impact? The virbrations from an air impact is known to kill the O2 senors.

The other thing that it could be is one of the extension wires for the O2 senors has a bad connection when you spliced them in to the O2 sensor wiring.

Totally forgot about that, im willing to bet that this is your problem.

It could very well be a damaged primary O2 or wire issue. Another possibility is a secondary O2 that isn't seeing enough difference in voltage change from 1 to 2, due to freer flow.

What's the actual code?

I'll never understand why people don't check the code and post it. Guessing a problem with no code is a needle in a haystack.

Eh, it's an extra step that many people won't be able to do on their own and/or won't be able to make heads or tails of on their own.

This is one of those only obvious-to-the-cognoscenti kinds of things :D

I keep a code reader in the car at all times.

Same here but auto parts stores have them. I mean if you have a normal car and you're not a car guy I get it...if you have a Z and just installed a serious part like LTH's it should be pretty obvious.

Well, after 5000 miles on my LTH, the Z threw a code: P015C - O2 Sensor Delayed Response. And it seems like they keep coming. The last one was P015A: O2 Sensor Delayed Response. I've tried a few tricks but non have worked so far. So, I'll keep clearing them until I get a tune from Z1 Motorsport. Also, I didn't use an impact wrench to install mine; no damage to O2 sensors.

What happens is people use a an impact to loosen/remove the bolts when removing the exhaust before removing the O2 sensors.

That's a primary O2 error on both banks. Can you datalog heater correction with uprev?

Either way, my guess is that you probably need to replace both sensors, although trying a replacement/re-soldering of the wire extenders first is an option...

I recommend getting the Denso part number 234-9104

You will need two -- cheaper than from Nissan and otherwise identical.

You may or may not need fresh wire extenders as well. The plug connectors will probably need to be reused (apparently there are at least two variants on our car...).

Ok. I did a little data logging. The code only pops up when my cars idling. It comes on about once or twice a week. But I usually only drive it on the weekend.

O2 sensor B1, S2:@ idle .02V / @ 3k, 3rd gear .8V

O2 sensor B2, S2:@ idle .02V / @ 3k, 3rd gear .8V

I'm 99.9% sure the Uprev tune will take care on this issue. I plan on getting it early next year. In the meantime, I'll keep clearing the code.

What are the heater corrections and voltage readings for S1 on both banks once warmed up... S2 is post cat.

Boo, just threw a p015a now after getting gas and pulling up to a light to stop. LTH's on maybe 5k? Hate codes.

What is that for?