threw my first code! yay! ugh
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threw my first code! yay! ugh
so a few weeks ago i came on the ol' forum to ask for help with the car. turns out i needed to clean the TB BAD! Well, that def fixed the problem...that day. now the car is running like total ****. i couldnt figure out the problem so i decided to flash the ecu back to stock. well long a behold...the check engine light starts BLINKING almost immediately. i look in my trusty ford manual and see its an engine misfire and that i should not accelerate hard and that i need to find a ford dealership ASAP!!! well now im panicing because im on the NJ turnpike and i just want to get home. the A/C is going on and off (blowing hot air then cold) so i turn that off all together. i get home and hook up the sct2 tuner to the car to find out wtf is going on and i get the code P0174 SYS TOO Lean 2. after some extensive research online i figure its either the plugs OR the MAF sensor. i decided to buy a can of MAF sensor cleaner and clean it. the check engine light is gone and im on my way to brooklyn (live in SI NY) to my girls and HOPEFULLY the problem is solved.
during my research of what the code meant, i came upon a fun fact. the MAF sensor in these cars is EXTREMELY susceptible to K&N air filter oil...i just recently cleaned and oiled the filter but that was AFTER i was having all these issues. so im just hoping the MAF sensor was filthy and the oil made it worse and me cleaning it got the job done.
if ANYONE has experience with the code P0174 SYS TOO Lean 2...please let me know how you fixed the problem. any help/input would be GREATLY appreciated. this is the first real problem ive had with this car and i just hit 52k miles
during my research of what the code meant, i came upon a fun fact. the MAF sensor in these cars is EXTREMELY susceptible to K&N air filter oil...i just recently cleaned and oiled the filter but that was AFTER i was having all these issues. so im just hoping the MAF sensor was filthy and the oil made it worse and me cleaning it got the job done.
if ANYONE has experience with the code P0174 SYS TOO Lean 2...please let me know how you fixed the problem. any help/input would be GREATLY appreciated. this is the first real problem ive had with this car and i just hit 52k miles
Last edited by slipnotovk; 8/12/11 at 11:57 AM.
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Well the CAI I have on there is one of I think two intakes that don't require a tune. I have the k&n on there. I actually ran it without a tune for about 2 years. Obv i got more power with the tune but it wasnt necessary to have
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I would say its something to do with re-learning.
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There are numerous posts in here about cleaning your TB and the car running like **** afterwards because of the sudden change in airflow therefore the computer has to re-learn some parameters.
There are posts here that give you instructions on how to speed the learning process up.
There are posts here that give you instructions on how to speed the learning process up.
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I saved this from one of the posts - don't know that you need to leave the battery unhooked all night though. Seems like I've read 20 mins or so is enough.
The idle learning process is simple. just unplug the battery overnight - then from a cold start, let the car start and idle for 8 minutes without touching the throttle at all. Now put the A/C on for 2 minutes, still at idle without touching the throttle at all and without shutting of the car. Now after 10 minutes of idling (8 without AC and 2 with AC), you can drive the car for approximately 10 miles... make sure it's not just highway, but stop signs, traffic slights, etc. You will have completed the idle learning process.
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From my 08 Owners Manual under "Maint & Specs/Battery"
• The vehicle may need to be driven 10 miles (16 km) or more to
Because your vehicle’s engine is electronically controlled by a computer,
some control conditions are maintained by power from the battery. When
the battery is disconnected or a new battery is installed, the engine must
relearn its idle and fuel trim strategy for optimum driveability and
performance. To begin this process:
1. With the vehicle at a complete stop, set the parking brake.
2. Put the gearshift in P (Park) (automatic transmission) or the neutral
position (manual transmission), turn off all accessories and start the
engine.
3. Run the engine until it reaches normal operating temperature.
4. Allow the engine to idle for at least one minute.
5. Turn the A/C on and allow the engine to idle for at least one minute.
6. Drive the vehicle to complete the relearning process.
some control conditions are maintained by power from the battery. When
the battery is disconnected or a new battery is installed, the engine must
relearn its idle and fuel trim strategy for optimum driveability and
performance. To begin this process:
1. With the vehicle at a complete stop, set the parking brake.
2. Put the gearshift in P (Park) (automatic transmission) or the neutral
position (manual transmission), turn off all accessories and start the
engine.
3. Run the engine until it reaches normal operating temperature.
4. Allow the engine to idle for at least one minute.
5. Turn the A/C on and allow the engine to idle for at least one minute.
6. Drive the vehicle to complete the relearning process.
• The vehicle may need to be driven 10 miles (16 km) or more to
relearn the idle and fuel trim strategy.
• If you do not allow the engine to relearn its idle trim, the idle quality of your vehicle may be adversely affected until the idle trim is eventually relearned.
When the battery is disconnected or a new battery installed, the [automatic] transmission must relearn its adaptive strategy. As a result of this, the
transmission may shift firmly. This operation is considered normal and
will not affect function or durability of the transmission. Over time the
adaptive learning process will fully update transmission operation to its
transmission may shift firmly. This operation is considered normal and
will not affect function or durability of the transmission. Over time the
adaptive learning process will fully update transmission operation to its
optimum shift feel.
Last edited by cdynaco; 8/13/11 at 12:29 PM.
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welp replaced all the plugs and now the car, when started, revs up to about 3k rpm, goes down to 400 shakes and dies. if i hit the gas, it starts knocking HARD and dies again so im afraid to start. this is (or was) the first time i ever did the plugs myself and im afraid ive really messed things up big time now. any thoughts?
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Well changing plugs shouldn't have done that. I would have waited until I had resolved the idle issue.
Which tune? Stock?
Did you clean the TB & MAF with proper cleaner? Spray too much on the MAF wire? Too much oil on that K&N? (I hate oil type filters) Did you disconnect battery? Did you let the ECU re-learn idle? Not enough info...
This is a long shot, but seems like I remember a similar issue on a post when someone cleaned the TB & MAF. They had problems getting it to idle and they went back and rechecked everything. Seems like either a wire or the way the MAF was reconnected wasn't perfect causing an air leak.
Maybe some ideas on these?
http://www.muscularmustangs.com/maf.php
http://forums.nicoclub.com/rough-idl...n-t417478.html
Which tune? Stock?
Did you clean the TB & MAF with proper cleaner? Spray too much on the MAF wire? Too much oil on that K&N? (I hate oil type filters) Did you disconnect battery? Did you let the ECU re-learn idle? Not enough info...
This is a long shot, but seems like I remember a similar issue on a post when someone cleaned the TB & MAF. They had problems getting it to idle and they went back and rechecked everything. Seems like either a wire or the way the MAF was reconnected wasn't perfect causing an air leak.
Maybe some ideas on these?
http://www.muscularmustangs.com/maf.php
http://forums.nicoclub.com/rough-idl...n-t417478.html
Last edited by cdynaco; 8/15/11 at 07:33 PM.
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Everything I read so far is good. BUT, don't disconnect the battery if you are do to be smogged. I had to replace my battery just before smogging and it wouldn't pass. There are five registers that have data in them and when you disconnect the battery they empty. Even after 400 miles of driving only two of them had enough data. It took almost a month of driving to get it to pass.
Point two. P0174 appeared while driving with a 87/89 Performance from
Tillman. This was after about 500 miles. I cleared the code. It happened again, I cleared the code again then put in the 91 All Out. Just happend the other day with that tune. I cleared the code and went to the track last night and it ran great.
My advice, just cleared the code.
Point two. P0174 appeared while driving with a 87/89 Performance from
Tillman. This was after about 500 miles. I cleared the code. It happened again, I cleared the code again then put in the 91 All Out. Just happend the other day with that tune. I cleared the code and went to the track last night and it ran great.
My advice, just cleared the code.
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Everything I read so far is good. BUT, don't disconnect the battery if you are DUE to be smogged. I had to replace my battery just before smogging and it wouldn't pass. There are five registers that have data in them and when you disconnect the battery they empty. Even after 400 miles of driving only two of them had enough data. It took almost a month of driving to get it to pass.
My advice, just cleared the code.
My advice, just cleared the code.
It is not how many miles so much as what you do when starting and driving the car.
My post #11 on this other thread explains what I have used:
https://themustangsource.com/f637/ne...2/#post6105347
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