ok if there happens to be anybody here that knows this stuff. most just look and do not help
i installed the egr valve and that code went away but i still get the gas cap and the code related to it is p0457 so i just put a 2016 chrysler 200 cap on the pacifica and now to see if the code goes away. i'm not holding my breath on this but may get lucky.

on another note i did a scan and i got these numbers in the live data using a harbor freight scanner

warm engine 2000 rpms
b1s1 .505 to .800
shrtftb1s1 % .075 to .780
b1s2 .055 to .095
shrtft % na g

monitors all checked good 1 dtc 1 pd dtc but the b1s2 moves around some i checked again and got at 2000 rpms .055 o .766 then back to .055 to .705 so either the sensor is failing or the cat is bad or dirty. this summer i'm going to try that lacquer thinner and see if ti cleans the cat while driving.

when i went thru the tests on the scanner all the evap tests passed so the gas cap makes me wonder what test it ran to determine the cap was loose when all the tests in the scanner said passed?

so if anyone does happen to have an idea just send it along. thanks.

 

Try clearing the gas cap code and see if it comes back. The scanner should be able to clear the code.

 

First of all
b1s1 .505 to .800
shrtftb1s1 % .075 to .780
b1s2 .055 to .095
shrtft % na g

is Oxygen sensors readings which have zero to do with a evap leak.
read this https://www.obd-codes.com/p0457

you have gas cap or something leaking rubber hose ect when the gas tank is pressurized looking for leaks. OS sensors readings are not involved with any of this.

 

code would not clear with scanner. i put the new cap on to see if the car would clear by itself after a few runs. just asking to see if some would confirm that or not thanks

 

i know the codes here are not gas pas codes i gave these numbers to see what some her thought might be going on in the 02 sensor and cat area.

 

What exactly do you think an issue is going on with the o2 sensors and cat?

that is a separate thing with the p0457 code

 

i don't quite know what may be going on with the 02 sensors, that is why i put the numbers here so maybe someone can see them and have an idea. there may be nothing at all and then again there may be something going on that i have to look into.

i know the p0457 is seperate i had 2 issues in that post. the p0457 somes up to the gas cap and i have tried a bunch of the i'm on the 4th now and this one is from a 2016 200 turns out they are the same. the reason i used the 200 cap was someone said the stant cap i got form the parts store would not work as it was not a cap from the mfg. but that cap is working fine on the 200 and rockauto says it is a oem part. or at least one that stant provides as oem to the mfg. that was the deal with the p0457 code. and for some reason the scanner will not clear out the p0457 code. the last time i took off the battery terminal.
so now with the 2016 200 cap i will wait a bit to see if the pacifica clears out that code, if not in a week or so i will remove the battery again. the car is doing good at setting up the monitors for pass, so not an issue there.

i put the 02 issues in just to see if there was something out of line with those number as some say the b1s2 should hold s bit more steady than what is is doing. and that the b1a1 may be an issue or the cat may be going bad. thanks for the help and questions. if you see something i need to check out let me know.

tell me what is the shrtft for the sensor banks? it see a percentage for some reason and i have no clue what that is. thanks

 

get an evap test performed at a qualifying shop that you like keep throwing gas caps at it forever if you like but will not fix it. The SHRTFT is short term fuel trim the sensor readings are normal nothing wrong. If there was an issue with the Cat the o2 sensors are whats determine that there is an issue with them.

 

So I have similar issue! It’s been a year now
I’ve had 3 extensive diagnostic test from Chryslers across the bay area here in California. I’ve replaced cap, fuel filler neck, hoses, my gas tank isn’t damaged, there’s never a visible leak when they do these tests and they can clear the code manually but 2-3 days later it comes back. My code is always the p0457. Any advice???

 

Wanted to add, sometimes car can jerk a bit or backfire while driving. Again, I’ve had dealerships diagnostics and they couldn’t find anything else 😒QUOTE=leyhendrix;121759]