so ive been having issues with the p0171 code lately coming on and i checked everything for leaks and cant seem to find any. my fuel system is running lean and now im getting a p0440 as well. any coincidence they are both on or are they not related to each other?
01' Z24 5 speed
422whp/400wtq
T4 Turbocharged
Built LD9
HP Tuners
Get some Mass airflow sensor cleaner and clean your mass airflow sensor (Be Careful)
Believe it or not I was getting that code and I put a new gas cap on the car and it worked! I couldn't find a vacuum leak anywhere either and no holes in my fuel system.
These 2 codes are related... how? You need a advanced scope or diag tool to tell, quickest way would be to smoke the evap system...
i hope your not serious about the maf cleaner........ theres never been a mass airflow sensor on any cavalier ever made.
ive been using hp tuners to monitor my long term fuel trims and they are sky high from start up until i turn the car off. I have changed the map sensor and both o2 sensors and its still throwing the p0171 code which is fuel system too lean bank 1.
01' Z24 5 speed
422whp/400wtq
T4 Turbocharged
Built LD9
HP Tuners
Sorry, didn't realize that they didn't have a MAS. I am new to Cavi's so I am learning!
Have someone clear your codes and then recheck.
The whole wait 5 min with the battery unhooked didn't work on my cavalier!
Sorry if I gave you bad info!
Thats because the PCM in this year stores codes, clearing the codes will not fix the problem, I love this forum... All sorts of bad advice... Full of win!
There has to be a good place to get info! Let me know if you find it!
Remember that un metered air can come from a cracked exhaust manifold before the 02s. Any exhaust work done recently? Have you tried the carb cleaner trick?
Beyond that I've seen 2 cases where pump volume intermittently fell below specs. Do you notice its harder for the car to achieve high RPMs?
ok well over a year later and i still have this issue. ive checked the intake manifold along with all the vacuum lines and ive replaced both o2 sensors and the map. Ive installed a new fuel filter and new plugs. Issue is still here and wont go away. I have a log from driving it in my hp tuners if anyone can tell whats going on from that? Im running out of ideas.
01' Z24 5 speed
422whp/400wtq
T4 Turbocharged
Built LD9
HP Tuners
I have the P0440 code and mine is coming from a hair line crack where the gas cap screws into. $35 dollar part on Rockauto.com. Use a bright flash light and look there, might be you're problem to.