CEL won't turn off!!
08-18-2007, 03:38 AM
#1
Junior Member
Thread Starter
Join Date: Jun 2007
Posts: 7
CEL won't turn off!!
So I had some money on me and decided to replace the entire stock air filter box with a new cone intake filter. I also took off the silencer box but i found a suitable cap from a plumbing store to cover it.
http://www.putfile.com/pic.php?img=6340254
Anyways, the problem is: Check engine light comes on. I've reset the system, i've used MAF sensor cleaner, i've got the code read, i've reset the code using the code reader, NOTHING WORKS! Simply put, the problem is that the computer is sensing a different oxygen intake and it reads this as a problem (when its really not). Now i'm not the only one whose done this mod, and im sure there's a way to get rid of the CEL. Would anyone know how?
Another minor problem that i'm having is that when i turn the ignition on, with the new filter, the initial rev is lagging. With the stock box, the rev felt loud and stable. With the air filter, the rev seems to choke up a bit, even though the drive is much more incredible. Is this a major problem or should i drive on it?
http://www.putfile.com/pic.php?img=6340254
Anyways, the problem is: Check engine light comes on. I've reset the system, i've used MAF sensor cleaner, i've got the code read, i've reset the code using the code reader, NOTHING WORKS! Simply put, the problem is that the computer is sensing a different oxygen intake and it reads this as a problem (when its really not). Now i'm not the only one whose done this mod, and im sure there's a way to get rid of the CEL. Would anyone know how?
Another minor problem that i'm having is that when i turn the ignition on, with the new filter, the initial rev is lagging. With the stock box, the rev felt loud and stable. With the air filter, the rev seems to choke up a bit, even though the drive is much more incredible. Is this a major problem or should i drive on it?
08-18-2007, 04:29 AM
#3
Senior Member
Scikotics
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Join Date: Nov 2004
Location: Minneapolis, MN
Posts: 9,731
Resetting the code does nothing to fix the issue. You reset a code after fixing an issue. If you messed with the airflow enough, you may be messing with the MAF readings, which in turn can cause fuel mix problems since the ECU is getting incorrect data for airflow.
Tell us what code you have and we can go from there.
But to clarify... it now revs lazilly and feels "choked", yet the drive is incredible??? In other words some loud noises make it worth it? I would put the stock airbox back in personally. That mod is simply pulling hotter air than stock, which is not an improvement overall.
Tell us what code you have and we can go from there.
But to clarify... it now revs lazilly and feels "choked", yet the drive is incredible??? In other words some loud noises make it worth it? I would put the stock airbox back in personally. That mod is simply pulling hotter air than stock, which is not an improvement overall.
08-18-2007, 01:36 PM
#4
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Join Date: Apr 2007
Location: Tampa, FL
Posts: 493
Your filter is too close to the MAF sensor.
Aftermarket intakes full article
If you're going to do a home-brewed intake you should research the aftermarket intakes that work and try to emulate one of those.
For aftermarket intake systems, turbulence across the MAF sensor is an all too common occurrence. Often times the MAF sensor is placed in close proximity to a bend, pipe joint, or weld. In the case of some hot air intakes (ie: Short Ram), the MAF sensor is mounted directly after a conical intake -- well before the air has a chance to smooth out.
When this turbulence occurs, the MAF sensor will suddenly see more or less air then it had previously. This will cause the engine management system to respond by making the engine run leaner or richer for as long as the error from turbulence occurs. The most noticeable driving characteristic associated with this would be a hesitation or flat-spot in the engine's power deliver. A worse case scenario would be the engine suddenly leaning out while under full throttle that resulted in engine damage.
Unlike the errors created by the different size of piping, there are no corrections one can make for an intake design that allows turbulence across the MAF sensor.
When this turbulence occurs, the MAF sensor will suddenly see more or less air then it had previously. This will cause the engine management system to respond by making the engine run leaner or richer for as long as the error from turbulence occurs. The most noticeable driving characteristic associated with this would be a hesitation or flat-spot in the engine's power deliver. A worse case scenario would be the engine suddenly leaning out while under full throttle that resulted in engine damage.
Unlike the errors created by the different size of piping, there are no corrections one can make for an intake design that allows turbulence across the MAF sensor.
If you're going to do a home-brewed intake you should research the aftermarket intakes that work and try to emulate one of those.
08-18-2007, 10:27 PM
#5
Junior Member
Thread Starter
Join Date: Jun 2007
Posts: 7
P0171
fuel trim bank one condition
causes:
1. if bank one and two codes set together suspect fuel pressure or MAF sensor
2. oxygen sensor defective
3. ignition misfire
4. fuel injector problem
That's the code.
I think what's left for me to do is buy the pipes and construct it myself, or just save up and buy a cold air intake..
fuel trim bank one condition
causes:
1. if bank one and two codes set together suspect fuel pressure or MAF sensor
2. oxygen sensor defective
3. ignition misfire
4. fuel injector problem
That's the code.
I think what's left for me to do is buy the pipes and construct it myself, or just save up and buy a cold air intake..
08-19-2007, 02:39 AM
#6
Senior Member
SL Member
Join Date: Apr 2007
Location: Tampa, FL
Posts: 493
^^That's not from a tC manual, we don't have a bank two.
Here's what you need to read:
P0171=system too lean
You're running too lean which is worse than running too rich, and could damage your engine. Put your stock airbox back in ASAP (and clear the CEL) until you figure out your next move.
If the CEL stays off with the stock airbox this will verify that your MAF sensor is not damaged.
Here's what you need to read:
P0171=system too lean
You're running too lean which is worse than running too rich, and could damage your engine. Put your stock airbox back in ASAP (and clear the CEL) until you figure out your next move.
If the CEL stays off with the stock airbox this will verify that your MAF sensor is not damaged.
11-05-2007, 04:12 AM
#7
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Join Date: Oct 2007
Location: Portland, Oregon
Posts: 2,461
i have the same problem.. but my CEL goes on and off... sometimes it turns off for a long time and sometimes it just keeps coming back on and then going away... it tends to stall itself when i do a fill up at the gas station so i was guessing it was resetting itself? anyone had this problem?
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