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I keep getting P0171B (bank 1 system to lean) code coming on and off.
Sometimes it will go away on its own from driving. Ive been researching possible problems. I can see the Air intake doesnt seat properly. The rubber sponge gasket doesnt sit properly. The top part that clamps down is missing a clamp. Would this stem the problem? I also noticed two holes were drilled into the rear exhaust after the muffler to give it some sound. Would that cause it?
Your P0171 (bank 1 lean) is likely caused by your poor intake seal…your bank 2 is most likely running lean also but your fuel trim on bank 2 isn’t high enough yet to cause a P0174 !!…rear exhaust holes will NOT cause this code to set. It’s a good idea to fill out your profile so if in the future you have some issues we can see what year, mods, etc you have…this is especially important when it comes to wiring differences.
The housing is definitely not sealed correctly. It's more of the base housing...do you know where I can buy one ? I didn't see anything on quick google search. Is it easy to change?
What about switching to the dual filter Y pipe I've seen on ebay. ?
No idea of what I’m looking at here but any seal, clamp etc downstream of the MAF has to be sealed…the air filter or any sealing surface upstream of the MAF sensor will not cause a P0171/P0174 !!
ok, the code was doing it before the seals were worked on. I had the intake manifold seals and oil pan gasket done because it was leaking oil...i dont understand how intake manifold seal would leak oil but it is what they told me.
I would bring it back to your shop and if they have a smoke machine they should be able to find the leak !!..an intake manifold leak would not cause an oil leak.
Now I accidentally overfilled the gas tank and immediately when I turned it on it thru a p0171 code again. Is a weak gas cap seal or housing flange a possible reason to cause that? Ive heard of gas caps causing check engine lights.
I really want to hear what C5diag says, but, overfilling should not cause the code. The gas cap can cause an engine light to come on but not necessarily the lean codes. However, I would make sure the gas cap is tight, reset the code, drive it and see if it comes back up. Good luck, and do what the other guys say. They are great. But make sure the gas cap is tight.
Now I accidentally overfilled the gas tank and immediately when I turned it on it thru a p0171 code again. Is a weak gas cap seal or housing flange a possible reason to cause that? Ive heard of gas caps causing check engine lights.
A gas cap will not cause a lean code…it will however cause an EVAP code…the PCV we assume is not causing your issue…I’d let your mechanic who should have a scan tool check your intake manifold gaskets but then again you said you had this issue prior to the gasket change…is this why he changed the manifold gasket ??…if he did he should have cleared the codes and then check his fuel trims to verify the repair…he should be able to diagnose this easily..if not he can contact one of us here on the Forum…don’t shot gun parts unless you gather some evidence and make an accurate diagnosis using scan data…at least you will be able to tell if it’s bank specific, a vacuum leak involving one or both banks, a MAF or a fuel delivery issue.
After reviewing this post, can you please post the model year of this car as there can be variances in troubleshooting fault codes by model year cars?
Regarding the OP post #6, that is a Varam Intake system and the airbox latch is broken off...details of this air intake system here VR-B2 (vararam.com)
As I too have this intake system, the Mass Airflow Sensor (MAF) installation is very specific in placement/orientation and could allow unmetered air into the intake if not properly installed.
Detailed install instructions here.pay attention to MAF installation steps 10 thru 14... http://www.vararam.com/VR-B2_instructions.pdf
P0171B Code
