NSBMW04

I changed my oil yesterday and replaced it with Mobil 1 0W-40 and replaced the filter with a Bosh. This is the first time I changed it my self with the help of a tool called Mighty Vac. I noticied today while driving the emission light came on I pulled over an went to tighten up my gas cap the light is still on. What else can I check?

luigi524td

Check the oil filler cap to be sure it's securely and correctly tightened.

Rizbel

I've had the same fault for over a year, and I even bought a new gas cap- with no solution. So I got to investigate.
I've read something about a DMTL or leak diagnosis pump that pressurize the fuel tank to check for leak, so I thought
that would be the first location to check.


I what I found made me laugh.


The rubber hose was not connected. I can't blame anybody but it's really suspicious that
it popped off by itself .

I'm going to reconnect it and hopefully that pesky P1434 code would go away.

pcy

NSBMW, if your CEL is on, you should read the diagnostics codes that are set. Note that gas cap is not the only thing that can cause emission light to be lit.

If you don't have an OBD-II code reader, take your car to auto parts store, they usually read the codes for free.

First read the code(s), note down those code numbers, then RESET the CEL with the code reader. See if the light comes back.

Rizbel

So far so good . "Tighten gas cap" and "Increased emission" messages are gone. Fault p1434 isn't showing when I scan with the CodeKey OBD II code reader.
I secured the connection with cable ties for added security. Saved myself some bucks by not going to the dealership for diagnosis and repair.

Next job: fault p0128, Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature).

BET530

I bought a new gas cap after I got the CEL, light is still on? If this was the problem, CEL should of gone away on its own???

pcy

if the only problem is the gas cap, yes, the CEL will go off on it's own after few drive cycles. If you don't want to wait until the light going off on it's own, you can RESET with any OBD-II code reader (or take the car to auto parts stores, they can RESET for free).