What's good everyone how's it going? Me 2001 Honda Civic LX 5-Speed my cousin 2005 Honda Civic LX 5-Speed March 25 we got free cold air intakes from a friend cause he didn't want them anymore but were still brand new. I know they are no no mods but we installed them and our check engine light stayed on for a month it took 5 minutes of driving when the light went off and has yet to come back on. We've even done out of county and out of state driving and the light hasn't come back on. What was it about the Cold Air Intake it killed the light?
You were running too rich/lean and the computer took a long time to adjust. You are supposed to get a tune done when you install an intake for that very reason.
Oh didn't know a tune was required... Ye the check engine light was so annoying our Civics. We were glad to see it turned off 5 minutes of driving with the cold air intake cause all it would bring up was an EVAP code for both. Our cars feel they have at least 130hp due to how quick plus we got that 4" JDM Titanium.
Did the cold air intake take out the MAF sensor? If it did that was probably your problem. Scan the car for codes perhaps to get more accurate info but could also be that for whatever reason your airbox was heavily restricted causing blockage in air intake so when installing the new "cold air" intake it freed up a lot of airflow. Typically these "mods" are not really no no, but kinda obnoxious if they are the only mod for some people. All it does is make the car louder pretty much. Like not a lot of people really need these pod filters ya know. Also just a tidbit. Can't be cold air intake if that said intake is directly next to the engine and exhaust lol.
True and it did indeed take out the Mass Air Flow Sensor.
Did a bit of MAF cleaner work to set the MAF back to work properly? (Sometimes, it's the oil on the intake filter that's the problem).
It's likely that it took that long for your car's computer to learn and compensate for the extra air flow a little bit at a time until it reached it's happy place.
Word up. Not gone lie me and my cousin were annoyed with the check engine light... Would stay on a few weeks then turn off itself then come right back on and was a repeat but this year it stayed on for a month and once we saw the light was killed after driving for 5 minutes with the cold air intake installed we were both happy it killed the light.
Conjecture: The computer had to adjust to a significantly different air/fuel ratio. Initially, the difference in air flow readings coming from the Mass Air Flow sensor were beyond standard specs. Eventually, the computer adapted the fuel air mix to conform to preset parameters. The Long Term Fuel Trim returned to an acceptable range and the "money light" went off.
To confirm this hypothesis, an OBD2 scanner that can scan for DTCs (Diagnostic Trouble Codes) and read fuel trims is required. The code itself went into history.
Hmmmmmmmmm.....
- BruceRee's suggestion is a good one:
- Clean the MAF: https://m.youtube.com/watch?v=NWCKvU2FmDc