Engine misfire

ALEXLESLIE

MEMBER
2006 HYUNDAI AZERA
3.8L
6 CYL
2WD
AUTOMATIC
150,000 MILES

The vehicle had a check engine light come on and the car was sputtering. I used a code reader, and it said my third cylinder is misfiring. So, I changed the ignition coil and spark plug, but it is still doing it. I also have had a problem with probably a clogged fuel system. Every time I get gas it comes right back up after putting a couple of dollars in. So, I’m thinking it may be a fuel injector issue. I’m wondering what it might be or what I should do next without wasting a ton of time and money.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

It is possible that these issues of the fuel filling and misfire are connected but that is not highly likely.

More than likely, you have two issues, but we should start with a fuel issue on the engine.

Let's start with fuel pressure and see what you have at the rail. If the fuel filling issue and misfire are related and you have low fuel pressure, then we need to suspect the filter is clogged.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

However, fuel filling issues are normally caused by an obstruction in the neck or in the tank. So, I would use an inspection camera and put it down the neck just to make sure it is clear and not blocked.

Then we can address this and move back to the misfire.

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

I am attaching the info on the filter which is part of the pump in the tank. The nice thing is you have an access panel, and you don't have to drop the tank.

This can also help to inspect what is in the bottom of the tank but let's start with the pressure and go from there.

Thanks

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