Driving hard with P0171 CEL. Any issue?
08-25-2014, 09:39 AM
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Driving hard with P0171 CEL. Any issue?
As far as I can tell, the P0171 CEL I have may be related to my ROW airboxes/filters, and car seems to drive fine across the RPM range (except for a slight vibration at idle and idle only).
I know with the lean code, it just means the ECU is dumping more fuel to meet the additional air than it normally would have, so my question is, will anything be harming the motor if the car is driven hard with this code? It sounds like some tuners will adjust parameters to make the CEL not trigger when the car is modded, but I’m not 100% sure.
With a 1 gear pull, car pulls consistent across the RPM band with no hesitation and no indications that it’s pulling timing.
As I’m going through trial and error trying to clear it for good, is there any harm if the car still sees some WOT pulls?
I know with the lean code, it just means the ECU is dumping more fuel to meet the additional air than it normally would have, so my question is, will anything be harming the motor if the car is driven hard with this code? It sounds like some tuners will adjust parameters to make the CEL not trigger when the car is modded, but I’m not 100% sure.
With a 1 gear pull, car pulls consistent across the RPM band with no hesitation and no indications that it’s pulling timing.
As I’m going through trial and error trying to clear it for good, is there any harm if the car still sees some WOT pulls?
08-25-2014, 01:32 PM
#2
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You can drive with that CEL but I wouldn't do hard pulls. Long term you are just reducing you gas mileage = more $$$ spend on gas.
I would try to pinpoint the root cause and fix it.
I would try to pinpoint the root cause and fix it.
08-25-2014, 01:40 PM
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08-25-2014, 01:47 PM
#4
MBWorld Fanatic!
As mentioned, recommended to not go WOT.
Why not take off the ROW boxes and see if your issue goes away?
You are driving a car that is protecting itself from damage yet want to drive it in the most damaging way possible... While nothing bad may come of it, you wont feel too good if it does.
Why not take off the ROW boxes and see if your issue goes away?
You are driving a car that is protecting itself from damage yet want to drive it in the most damaging way possible... While nothing bad may come of it, you wont feel too good if it does.
08-25-2014, 07:31 PM
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507 SEDAN
I believe that code relates to your MAF's. Make sure that your MAF's are installed correctly. They might go in on opposing sides, depending on your box. Meaning that on bankA(left) the sensor goes in right-side up. And on bankB(right) the sensor goes in upside down. I'm not sure if that's the case with your box, but check and see. That was the case with the last Carbonio I ran. What I would do is make sure the sensors are installed properly and then re-seat the filters. Then button the air box back up tightly, with a nice seal. What filters are you running? Oiled or not?
A great test is to hook up the OEM boxes as a "test". I know you don't have them, but I'd try to find some to test.
Also, I would check the MAM(mass air meter). That regulates the amount of fuel with the amount of air coming in.
A great test is to hook up the OEM boxes as a "test". I know you don't have them, but I'd try to find some to test.
Also, I would check the MAM(mass air meter). That regulates the amount of fuel with the amount of air coming in.
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08-26-2014, 12:32 PM
#8
Same here...when I had my idle lean CEL come on I ignore it because I knew what it was...it all happened after adding my CAI kit. I have a Scan Tool and can see what the code(s) is and erase. 
An Idle lean code is just that, an Idle lean code. The ECU looks at your STFT and LTFT to correct and push to a 14.7 stoich. I've tuned cars to run as lean at 16.1 AFR at idle and part throttle and never had any issues...in fact, MPG improved to due lean cruise.
If you have a tune in your car, have your tuner add a little fuel to your idle table usually around the 2500 to 2800 Hz on your low frequency MAF settings and you should be fine.
An Idle lean code is just that, an Idle lean code. The ECU looks at your STFT and LTFT to correct and push to a 14.7 stoich. I've tuned cars to run as lean at 16.1 AFR at idle and part throttle and never had any issues...in fact, MPG improved to due lean cruise.
If you have a tune in your car, have your tuner add a little fuel to your idle table usually around the 2500 to 2800 Hz on your low frequency MAF settings and you should be fine.
08-26-2014, 02:41 PM
#9
MBWorld Fanatic!
Same here...when I had my idle lean CEL come on I ignore it because I knew what it was...it all happened after adding my CAI kit. I have a Scan Tool and can see what the code(s) is and erase.
An Idle lean code is just that, an Idle lean code. The ECU looks at your STFT and LTFT to correct and push to a 14.7 stoich. I've tuned cars to run as lean at 16.1 AFR at idle and part throttle and never had any issues...in fact, MPG improved to due lean cruise.
If you have a tune in your car, have your tuner add a little fuel to your idle table usually around the 2500 to 2800 Hz on your low frequency MAF settings and you should be fine.
An Idle lean code is just that, an Idle lean code. The ECU looks at your STFT and LTFT to correct and push to a 14.7 stoich. I've tuned cars to run as lean at 16.1 AFR at idle and part throttle and never had any issues...in fact, MPG improved to due lean cruise.
If you have a tune in your car, have your tuner add a little fuel to your idle table usually around the 2500 to 2800 Hz on your low frequency MAF settings and you should be fine.
I don't think you'll damage the car. But I'd find power in other ways or at least have it tuned properly.
08-27-2014, 04:03 AM
#10
