Engine The Engine Light Is On??

The Engine Light Is On??

I put my CAI in my rola, a couple of days later my engine light comes on. I disconnected the negative on my battery to reset it. The light comes back on in a day or so. Does anyone have any ideas on why this is happening before I spend $60 for an engine diagnostics?

check to make sure all the connections are secure especially the vacuum hoses. If you drove your car with the light engine on, you might have damaged something. Go to the dealer and put everything back to stock if the light is still on. They'll warantee it.

Thx, but i already thought about checking all the connections. Would you have any idea what the problem would be, example: maybe the air sensor, etc.....What could I have accidently touched, broke or moved to cause the light to come on?

A CEL with the CAI is most often a lean mixture. It's usually caused by the MAF sensor getting an inaccurate reading. This happens A LOT when you mess with the intake system. MAF sensors are touchy. Things you can do: clean the MAF sensor (oil from the filter could be on the heated wire), buy an S-AFC to correct the problem or just live with it and hope you're not detonating, which will destroy your engine. The detonation happened on my '03 Corolla 5-spd with the AEM CAI. NOT COOL!!!

And driving for long, extended periods of time with the CEL could damage something. But, no long than this, probably not. If the ECU hits a fault code, it defaults to a protective spark timing and fuel injection curve to prevent damage.

Late,

Trav

sometimes the MAF sensor isn't properly connected or some dirt might have gotten in it while it was removed. Try removing it and cleaning it. If this doesn't solve the problem, then i suggest put it back to stock and take it to the dealer so they can fix it.

aight....good lookin. Imma try both yall ideas tomorrow morning. Thanks again!!
One more thing.....ya, umm.....im gonna need to know what CEL, MAF, S-AFC, & ECU stand for. Thank

Is it an AEM CAI?

MAF sensor = Mass Air Flow sensor
ECU = Engine Control Unit
CEL = Check Engine Light
S-AFC = Super Air Flow Controller (made by A'PEXi)

Aside from cleaning the MAF sensor, which we all recommend, make sure it is sealed well to the intake tube. I used vacuum grease and teflon tape around the o-ring. Also, make sure it is sealed to the throttle body good. Remember, ALL air that comes into the engine HAS to be measured by the MAF sensor. Otherwise, with un-metered air entering the engine (vacuum leaks) or the MAF sensor just not getting an accurate reading (which is what I think your problem is), then you end up with a lean mixture (too much air/not enough fuel - in your case it's too much air...or at least that's what the ECU thinks).

Late,
Trav

use electrical parts cleaner for the MAF sensor - don't touch it with anything....unless you want to risk breaking a fragile and VERY expensive part ($400). Just spray some electrical parts cleaner (available at any auto parts store) through it and that should be fine.

Some people use a q-tip and alcohol....and I would just be too leery of breaking that fragile little wire in there.

Trav

Aight, I did what you told me to do and tried cleaning the MAF with the electrical parts cleaner and put it back in. I reset the CEL. Now I wait and pray that it worked. Thx for the help. appreciate it! One more question.......what do u mean by detonation and how do you know thats what might be going on?

Detonation or engine knock - abnormal combustion. That is what happens with a lean mixture. Normally, the spark plugs fires, the cylinder reaches top dead center, the ignition drives the piston back down (power stroke). The flame front should be very steady and controlled.

Funny thing about lean mixtures is that the temperature of combustion is A LOT hotter than stoich or rich. Adding fuel cools combustion down whereas removing fuel or adding too much air (lean) will heat up combustion. With a lean mix, the initial combustion after the spark is so hot that it causes a huge pressure and temperature spike. This will cause another (and probably several) flame fronts to ignite spontaneously. That's when you hear the can of marbles rattling around in your engine. It's like slamming it with a hammer on each power stroke. It will erode pistons, bend rods, ruin bearings and most generally destroy your engine. It usually happens in low to middle rpms. High rpms, things are happening too fast to really get the full effect.

Late,
Trav