p0171 weird
02-16-2015, 07:46 PM
#1
2nd Gear Member
Thread Starter
Join Date: Dec 2011
Location: california
Posts: 377
p0171 weird
guys so i went and cleaned my TB and MAF with CRC cleaner took my stock intake off and install my steeda cold air intake again. bolt everything back up load my tune and started the car. CEL came on after 10 mins so i plug my sct4 to see what it was and it was p0171 too lean on bank 1. cleared the CEl and drove the car for about 5 miles. went back home and the following morning i started the car and again CEl p0171 came on again, cleared it and drove the car for a few miles about 40 or so miles. 2 days pass and CEl never came back on. did the problem fix it self? or did my computer said F%$Ked it you're just going to reset me again.
02-19-2015, 10:49 AM
#3
6th Gear Member
Your computer said "F%$Ked it you're just going to reset me again".
It's possible that you were on the line with regard to throwing the CEL when you first installed the CAI and tune (especially if you disconnected the battery which would have reset a number of on-board parameters). As long as it's not throwing the CEL, I'd say your fine. Ford engineers would be geniuses if they could get a computer to act as stupid as people (close but no cigar).
It's possible that you were on the line with regard to throwing the CEL when you first installed the CAI and tune (especially if you disconnected the battery which would have reset a number of on-board parameters). As long as it's not throwing the CEL, I'd say your fine. Ford engineers would be geniuses if they could get a computer to act as stupid as people (close but no cigar).
02-21-2015, 02:54 AM
#4
2nd Gear Member
Thread Starter
Join Date: Dec 2011
Location: california
Posts: 377
02-21-2015, 02:59 AM
#5
2nd Gear Member
Thread Starter
Join Date: Dec 2011
Location: california
Posts: 377
Your computer said "F%$Ked it you're just going to reset me again".
It's possible that you were on the line with regard to throwing the CEL when you first installed the CAI and tune (especially if you disconnected the battery which would have reset a number of on-board parameters). As long as it's not throwing the CEL, I'd say your fine. Ford engineers would be geniuses if they could get a computer to act as stupid as people (close but no cigar).
It's possible that you were on the line with regard to throwing the CEL when you first installed the CAI and tune (especially if you disconnected the battery which would have reset a number of on-board parameters). As long as it's not throwing the CEL, I'd say your fine. Ford engineers would be geniuses if they could get a computer to act as stupid as people (close but no cigar).
02-22-2015, 05:49 PM
#6
your computer goes through a readiness drive cycle when you drive it. usually after a check engine light is reset it will say that the checks are incomplete. as you drive it monitors everything and if one of the readiness perimeters are out of range it will throw a code.
if you've driven it over 50 miles or so and still no light, theres a good chance the computer was freaked out but it corrected the issue.
i see your in California, when you take your vehicle in for smog they check to make sure you have no incomplete readiness monitors. if you do, your car will fail. so if you had a check engine light on, reset it and went straight for smog, it would fail, it has to have gone through all the cycles to pass. CA got stricter every year, it used to be able to pass with 2 incompletes, then it was one, now its none if its over 2000 or something
the monsters are
Catalyst (CAT)
Heated Catalyst
Evaporative (EVAP) System
Secondary Air System
Oxygen (O2) Sensor
Oxygen Sensor Heater
EGR (Exhaust Gas Recirculation) and/or VVT System
if you've driven it over 50 miles or so and still no light, theres a good chance the computer was freaked out but it corrected the issue.
i see your in California, when you take your vehicle in for smog they check to make sure you have no incomplete readiness monitors. if you do, your car will fail. so if you had a check engine light on, reset it and went straight for smog, it would fail, it has to have gone through all the cycles to pass. CA got stricter every year, it used to be able to pass with 2 incompletes, then it was one, now its none if its over 2000 or something
the monsters are
Catalyst (CAT)
Heated Catalyst
Evaporative (EVAP) System
Secondary Air System
Oxygen (O2) Sensor
Oxygen Sensor Heater
EGR (Exhaust Gas Recirculation) and/or VVT System
02-22-2015, 11:43 PM
#7
2nd Gear Member
Thread Starter
Join Date: Dec 2011
Location: california
Posts: 377
your computer goes through a readiness drive cycle when you drive it. usually after a check engine light is reset it will say that the checks are incomplete. as you drive it monitors everything and if one of the readiness perimeters are out of range it will throw a code.
if you've driven it over 50 miles or so and still no light, theres a good chance the computer was freaked out but it corrected the issue.
i see your in California, when you take your vehicle in for smog they check to make sure you have no incomplete readiness monitors. if you do, your car will fail. so if you had a check engine light on, reset it and went straight for smog, it would fail, it has to have gone through all the cycles to pass. CA got stricter every year, it used to be able to pass with 2 incompletes, then it was one, now its none if its over 2000 or something
the monsters are
Catalyst (CAT)
Heated Catalyst
Evaporative (EVAP) System
Secondary Air System
Oxygen (O2) Sensor
Oxygen Sensor Heater
EGR (Exhaust Gas Recirculation) and/or VVT System
if you've driven it over 50 miles or so and still no light, theres a good chance the computer was freaked out but it corrected the issue.
i see your in California, when you take your vehicle in for smog they check to make sure you have no incomplete readiness monitors. if you do, your car will fail. so if you had a check engine light on, reset it and went straight for smog, it would fail, it has to have gone through all the cycles to pass. CA got stricter every year, it used to be able to pass with 2 incompletes, then it was one, now its none if its over 2000 or something
the monsters are
Catalyst (CAT)
Heated Catalyst
Evaporative (EVAP) System
Secondary Air System
Oxygen (O2) Sensor
Oxygen Sensor Heater
EGR (Exhaust Gas Recirculation) and/or VVT System
bbk catted x pipe
steeda CAi
bama 91 tune
and on the tune i told bama that i have a catted bbk x pipe so it can't be the tune can it?
i did remove the TB and cleaned it with the CRC(TB) and also sprayed the MAF with the CRC(MAF) and put all those back together. also when i removed the o2 from my stock cats i put some anti seize on the thread of the 02 sensor.
should i go with the spray with carburetor cleaner method to find the leak from the CAi to the TB?
02-23-2015, 10:21 AM
#8
5th Gear Member
Join Date: Oct 2009
Location: Maui
Posts: 4,752
damn thats sucks bro yeah the CEL came back on today but its weird because i have driven it for more than 50 miles more like 100+. here are the things that i have installed
bbk catted x pipe
steeda CAi
bama 91 tune
and on the tune i told bama that i have a catted bbk x pipe so it can't be the tune can it?
i did remove the TB and cleaned it with the CRC(TB) and also sprayed the MAF with the CRC(MAF) and put all those back together. also when i removed the o2 from my stock cats i put some anti seize on the thread of the 02 sensor.
should i go with the spray with carburetor cleaner method to find the leak from the CAi to the TB?
bbk catted x pipe
steeda CAi
bama 91 tune
and on the tune i told bama that i have a catted bbk x pipe so it can't be the tune can it?
i did remove the TB and cleaned it with the CRC(TB) and also sprayed the MAF with the CRC(MAF) and put all those back together. also when i removed the o2 from my stock cats i put some anti seize on the thread of the 02 sensor.
should i go with the spray with carburetor cleaner method to find the leak from the CAi to the TB?
Yes try the carb cleaner leak test. If your rpms vary at all when you spray it then you know you have a vacuum leak.
02-23-2015, 01:31 PM
#9
2nd Gear Member
Thread Starter
Join Date: Dec 2011
Location: california
Posts: 377
thanks bro, should i check only around the tb area, since thats the only part i actually messed with. anything before the MAF sensor should be ok right? also would a leak between the exhaust manifold and the bbk catted x pipe cause the the cel to come on?
02-26-2015, 12:08 AM
#10
spray round the TB and intake manifold. also valve covers and pcv hoses
if you have access to a smoke machine that would be awesome. smoke test it into the booster line to the engine.
i have a feeling that the MAFS may be damaged. it happens quite often if you clean them. its safer to leave them alone and only attempt to clean them if your throwing a code for it.
do you have access to a scan tool with live data? you could see what the MAFS is reading and be able to tell if it is out of range.
Usually a mass air flow sensor throws a code for lean on bank 1 and 2 but occasionally it is just the one.
you could also check live data on the 02 sensors. see how it compares from bank 1 and 2.
(sorry i know I'm throwing a lot of info out but unfortunately its a very vague code)
im a mechanic so feel free to keep asking. Happy to help
if you have access to a smoke machine that would be awesome. smoke test it into the booster line to the engine.
i have a feeling that the MAFS may be damaged. it happens quite often if you clean them. its safer to leave them alone and only attempt to clean them if your throwing a code for it.
do you have access to a scan tool with live data? you could see what the MAFS is reading and be able to tell if it is out of range.
Usually a mass air flow sensor throws a code for lean on bank 1 and 2 but occasionally it is just the one.
you could also check live data on the 02 sensors. see how it compares from bank 1 and 2.
(sorry i know I'm throwing a lot of info out but unfortunately its a very vague code)
im a mechanic so feel free to keep asking. Happy to help