CEL comes on during long drives

[highcaliber]

I just drove my '09 up to Sacramento and back. It takes about 7 hours to drive up there from where I live. Both on the way there and on the way back my check engine light came on about 5 hours into the drive.

I have an OBDII code reader which lives in my emergency kit in the trunk (a leftover habit from a previous vehicle with CEL issues) I plugged in and pulled the code - it was for a lean condition. I let it stay lit, to see if it would self-correct and after 3 or 4 starts and 60 or so miles of driving - it went out.

Then it came back on again on the drive home. Again about 5 hours into the drive. No driveability issues, same code.

When I bought the car it had an aftermarket cone filter on it. I have a hard time buying the idea that the crappy A/F would be the source of the lean condition.

Car has 38,000 miles on it now - seems early to me to be an O2 sensor problem.

Ideas, anyone?
For that matter, does anyone have a factory air box that they want to sell, so I can avoid any warranty issues if I have to take this thing to the dealer?

[razorlab]

It's a fuel trim too lean code caused by your intake messing with the MAF sensor

- Bryan

[Tuqwik4u]

Bryan's Right, And about you warranty did you get your car from a private owner? Or from the dealership with the intake on it?

[MikeW-RRE]

Take the cone off and put the stock air box back on. It isnt making any power and will just make problems for you. Some are even untuneable. I see all kinds of weird dips and messy AFRs that cant be tuned out. As the air turbulance inside the filter changes with increasing air velocity, it concentrates differing amounts of air on the actual aif flow sensor. They sound cool though!

Mike W

[MTZL]

Put the stock one back in.
throw the cone filter far away from the RA as possible.

[highcaliber]

Hmm.
I stand corrected. You guys have more experience with these cars than I do. I've never seen this before - installing a different A/F causing a CEL.. Talk about hypersensitive.

So who has a factory airbox that they want to part with? I checked the classifieds and PM'ed one seller. No reply yet.

Edit: Bought the car from Victorville Mitsubishi, came with the cone filter on it. I won't go into detail about my great experiences with the clowns at that dealership, but if you care to hear about it, PM me.

[MikeW-RRE]

Google "installed intake got CEL" and you will come up with more than you can read. It happens :-)


MIke W

[bmanuhutu]

if u need a stock airbox, complete set

http://clubralliart.com/showthread.php?t=475

mike from RRE removed the stock one to put on an injen test intake, he can vouch that this was a brand new car

[Looney Tuning]

If you cannot find a stock box, then the CEL can be turned off by adjusting either the MAF scaling tables or the injector latency tables.

What happens is on long drives the fuel trims build up and thy go WAY positive. The max positive trim on these cars is +12.5%. Basically the ECU sees a lean condition and starts dumping 12.5% fuel to correct it. Once it cannot dump any more the CEL comes on.

Most tuners can fix that for you. I know I can