So I get a CEL on my '04 G35 Coupe at 35,100 miles about a week ago.

It's not time for an oil change yet, and the last major service to it was the 30k mile premium service done on 26,700 miles last year. The day that the CEL turned on, the RPM was pretty low on start-up (granted it was a hot day), normally, on the first start-up of the day, it averages around 1k RPM. That time, it was around 500RPM.

So after reading the in-dash screen saying check the fuel cap, I went to the nearest gas station and filled up... tightened the cap, but the light was still on. Maybe about 2 days later, my TPMS light goes on. TPMS should be an easy fix, but yeah.... just throwing it out there.

Then yesterday, I decided to go to the dealership to check it out, but after parking the car, and then restarting it, the CEL wasn't there. Just decided to go away.... Maybe its the aura of the Infiniti dealership, but I just don't see how it can just turn off after a week of being on and the fuel cap being tightened.

Is it possible to look up the CEL code even if the light isn't on there anymore? My guess is that the CEL was a "premium 30,000 mileage service is overdue" warning, but I'm hoping you guys would know the answer to this one....

Mods currently on the car is a catback and rims.

 

I'm not sure if you're joking about the 30K maintenance thing, but our cars don't do that. Some other Nissans literally do turn on the check engine light at various milleage intervals. I know my old Sentra used to do that every 60K miles and you had to flip this switch that was hidden under the passengers side interior plastics to reset it.

If the CEL was on, you can pull the code if you have an OBD-II scanner. It saves them for quite a while. If the light is off, I wouldn't worry about it unless it comes back on though.

 

The cel should stay stored in the ecu until you do a hard reset either by disconnecting the battery or by disconnecting the ecu completely. It'd be easy enough to take up to autozone or advanced and they read those codes for free.

 

Autozone doesn't read them for free anymore.. Well at least not in the Los Angeles area.. They haven't for a few months now.

 

Really? Thats weak. They still do it for free over here.

 

They still do it for free in most other states. I read something a few months ago that they stopped doing it just in Cali because some dumbass Cali customer tried to sue them or something for liability issues somehow from something stemming from an OBD-II reading that they performed.

 

haha someone would!

 

Sounds like a typical gas cap loose situation. If you gas cap is left loose, the evap system thinks that there are fuel vapors leaking from the car and will trigger the light. After you tighten the cap, the ecu needs a few heat cycles before it runs a self diagnostic again. Heat cycles are basically getting the vehicle up to normal operating temp. After it runs the self diagnostic, which can take a few days depending on how much you drive, it will reset itself.

I know on hondas, it only takes one heat cycle but you have to run it at highway speeds for about 10-25 miles before it resets or it just takes a few days. On my QX4, it takes a few minutes of highway driving.

 

^ thansk for that info cloud.