Q: Check engine light is on. The gas cap is okay and the vent sensor by crankcase seems okay too. What could it be?

asked by on February 17, 2017

Dignotic test showed air flow, checked gas cap, some sensor of or by crankcase. Any thing you could help with?

My car has 102376 miles.
My car has an automatic transmission.

The issue could be the evaporative emission vent purge valve on the vapor charcoal canister. I recommend using a sniffer that is used for butane and check for a fuel leak around the vent purge valve and see if there is a gross leak. If so, then I recommend replacing the vent purge valve on the vapor charcoal canister. If you need further assistance with your check engine light being on, then seek out a professional, such as one from Your Mechanic, to help you.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Transmission fluid is leaking

Greetings. It is somewhat expected for seals to stop preventing leaks after a few years of usage. If it is the front seal as you believe it to be, the transmission will have to be dropped to replace it. There...

Car is randomly misfiring

There are a number of things that may cause this such as a faulty or dirty mass air flow sensor, a potentially a bad idle air control valve, or dirty fuel injectors. The mass air flow sensor is a unit...

Leaking coolant, visible from reservoir. Has crack in reservoir.

Replacing the reservoir and hoses since they are cracked is the first step. The second step is to figure out why the coolant is creating too much pressure in the tank. This may be caused by a variety of reasons...

Related articles

3 Reasons Your Car Smells like Rotten Eggs
A sulfuric or rotten eggs smell indicates an excess of byproducts left over from failed combustion. Removing the smell requires part replacement.
How to Replace a Carburetor on Most Cars
A carburetor replacement involves the air cleaner, vacuum hose, car fuel line, and a number of other parts. This complex procedure varies by vehicle.
How Can You Tell That Your Fuel Pump Isn’t Working?
The The fuel pump is responsible for getting fuel out of the gas tank and up to the engine. The pump itself is usually located inside the gas tank. There are a handful of symptoms to look out for that...