help me get rid off my code

N

newyorkjets00

New member
help me get rid of my code

Hey everyone! I just bought a 2000 L 2 weeks ago and the check engine light came on when i got home that day, so i called the guy immediately and he said its never came on the 6 years that hes had it. ( really nice guy) Said his wife put 87 in it about a week before i got it and he didnt drive it that week due to her being pregnant and trips back and forth to the e.r. So we have done some talking about the code ( p0171) he says its the gas and it will go away after i change the fuel filter. Should i try that or is that not going to fix it? He also had a JLP Thunder Tube and JLP ram air box on it that he took off, and put the stock tube and a LFP 12" deluxe powerstack c.a.i on it. This is what a google search told me.
"This causes the maf voltage to read lower, and conversly less fuel is mixed in, then the o2 sensors read the lean condition, and when they reach a certain threashold of adding more and more fuel you get the lean codes."

Also says i need to retune my truck or put the stock maf sensor back on. i can write out the rest of the stuff done to my truck if i need to, any help i would appreciate!
 
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Cheer up, here's a few possibilites. My ses light has been on for 3 months, I have been waiting for the new paint on my red 99 to cure before handing it over to the shop to fix it. Good luck.

Check Engine Light Code P0171

System Too Lean - Bank 1

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How does a P0171 code trigger the check engine light? This code will trigger the check engine light as follows:

The adaptive fuel strategy in the vehicle's computer constantly monitors the fuel delivery system to make sure the engine is running at an optimum air to fuel ratio, which is 14.7:1. The computer adjusts injector pulse width to regulate the amount of fuel going into the engine. The oxygen sensors relay information to the Powertrain Control Module (computer), informing it of the oxygen content in the exhaust. This information is translated by the computer, and used to determine if more or less fuel is needed. The computer will then adjust fuel flow (and possibly other related engine operating characteristics), to keep the correct air fuel mixture. This loop continues as long as the engine is running. Please refer to our article Oxygen Sensor Code Diagnosis for more info on this system. A P0171 check engine light code is set when the computer has reached a rich calibration limit and can not add enough fuel to maintain the correct mixture.

Possible Causes:

Refer to our Oxygen Sensor Code Diagnosis article for a list of all possible causes. The following is an overview of P0171 check engine light code possible causes.

Fuel System:

Leaking or faulty fuel pressure regulator
Plugged or dirty fuel filter or lines
Fuel pump weak or defective check valve
Injectors leaking or faulty
Low fuel pressure or running out of fuel
Leaking EVAP system components
Faulty FRP (Fuel Rail Pressure Sensor)

Air Intake System

Vacuum leaks
Contaminated, damaged or faulty Mass Air Flow sensor
PCV valve leak or stuck open
Air induction turbulance caused by wrong filter
Oil dipstick not seated
Air leaks after the Mass Air Flow Sensor (MAF)
Oil coated aftermarket air filter

Exhaust System

Any exhaust leak before or near the oxygen sensors

EGR System

Vacuum line disconnected from EGR System Module (ESM)
EGR valve, tube or gasket leak
EGR vacuum regulator valve leaking

Secondary Air Injection System

Mechanically stuck secondary air injection valve
 
thats alot of stuff to check... there is a hole on the bottom of the intake tube about the size of my thumb. its inbetween the maf sensor and the intake. a buddy is bringing me his since his k and n came with a tube so i will see if that makes a differance.
 
I think I know where your problem is

On our cold air kits we install a new air charge sensor in the base of the filter neck. a small whole is drilled and a ACS in installed. If you are saying there is a whole there, then your intake is sucking in outside air and there is no ACS.

Having put some 87 octane fuel in the tank would not require a fuel filter change. However if the fuel filter is old and has more than 6K on it, then yes replace your fuel filter.

Both the LFP and the JLT CAI have the same size 12" Power Stack filter.
Hope this information helps. Have an awesome monday evening!

Mark/LFP
1-281-385-5339
Mustang Performance Parts | Dodge Performance Parts | Lightning Force Performance Parts Store
" Check IT Out "
 
there is a hole the previous owner made and stuck the acs in.. but there is another hole on the other side of the m.a.f sensor in the rubber factory tube...
 
Congrats on your purchase... If there is a hole that is open and not plugged then that is more than likely the problem... 87 octane fuel will not hurt anything as long as the supercharger is kept in the vacuum range and doesn't go into full boost... I would change out the fuel filter as that is a problem with these trucks and try to plug the open hole in the intake tube and see if that turns the light off...
 
thanks im liking the truck so far!! i replaced the tube with a buddies stock one he had last night but when i run my code reader its still coming up.. i cleared it earlier so we will see if it comes back on. i tried to post some pics of the hole last night but they wouldnt work??
 
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Did you ever figure out your problem and get the code figured out? I have the same code on my truck and for the life of me can't figure it out either......
 
Hate to say it, and surprised no one else has mentioned it. Usually the culprit for P0171 and P0174 is a broken vacuum elbow on the backside of the intake, below the supercharger. The supercharger needs to be removed in order to replace it. And the best bet is not to replace it with another stock piece. Replace it with some high temp 3/8 transmission line and a double 3/8 hose barb. This way it will never be a problem again.

Mine is currently throwing the P0171 and 174 codes. It started with just the p0171, and I reset it three times using the scanner I bought from Auto Zone. However this latest time it threw both 171 and 174, lean banks 1 and 2. So I am going to have to do this soon. I have read where other folks have lived with the light on for these codes for several years with no problems. For now I am just staying out of full boost until I can fix it.

BTW: when my truck first started throwing the code was after a fill up of 91 octane Shell with ethanol. I refilled the tank with 93 octane Sinclair and reset the code. Two weeks later it came back on again so I replaced the fuel filter and reset it. It came on again two weeks later, so I cleaned the MAF. It came on again today, so I am assuming the worst and that it is the vacuum elbow behind the manifold. Its quite common on Lightnings, and always clears the code permanently.

VV Click here VV
Here is a thread from another site that has a picture of the noted elbow.
 
Sweet thanks man I'll have to check it out. Well actually have one of my friends with long skinny arms since I'm built like T-Rex pwhahahaha. And the elbow your talking about with the hose coming out of it is the black elbow all the way at the bottom by itself right? Just wanted to make sure I'm checking the right thing.
 
McNastyLightnin said:
Sweet thanks man I'll have to check it out. Well actually have one of my friends with long skinny arms since I'm built like T-Rex pwhahahaha. And the elbow your talking about with the hose coming out of it is the black elbow all the way at the bottom by itself right? Just wanted to make sure I'm checking the right thing.
Click to expand...

It's at the base of the intake in the center. It's a PITA to get to, but it does cause issues. During a IC clean I plugged mine up from the inside after deleting the PCV system.
 
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1LethalSVT said:
It's at the base of the intake in the center. It's a PITA to get to, but it does cause issues. During a IC clean I plugged mine up from the inside after deleting the PCV system.
Click to expand...

Yes you can plug it if you delete the pcv system. If you do not do that you will have oil all over the place. I am going to replace mine with some 400 degree transmission hose and a double 3/8" hose barb. Put the hose on the elboe and connect it to the rest of the system with the double barb. Should never cause the problem again.

Currently I am just doing all of the easy stuff and re-setting the computer. Eventually I'll be done all the easy stuff and be left with one eventuality, the PITA hose.
 
Gotcha man thanks trucks been running like crap and haven't been able to figure it out I hope this is it. I've checked all other hoses and stuff that I could reach so this has to be it.
 
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