hesitation and misfire

Question

2016/Honda/Accord 99000 miles, CVT transmission Just recently got this car from a dealership, everything has been fine until the cold weather has hit. Now if it's under 40 degrees fahrenheit and I don't let my car warm up it'll hesitate a bit, but it usually goes away after it's warmed up. The first morning I had the issue I couldn't even drive, it was around 25 degrees and it started hesitating and misfiring (flashing check engine light) at 3000 RPMs, then I lost all power and couldn't go over 5 MPH without hesitation and misfires. I didn't get any engine codes when I got it scanned at Autozone.

MountainManJoe · Accepted Answer

Posted by: @colby90024 Just recently got this car from a dealership, unless disclosed and sold as-is, dealers are required by law to not sell cars with pre-existing conditions (and misfire is a bad one). There is a time limit for this, but it's something you should look into.   There are many possible causes for an engine misfire. There's a misfire article on our FAQ page, so go there and that should get you started.   Also be aware that Hondas need their valves adjusted every 100k, so you're due.   https://www.youtube.com/watch?v=P7wI4EtZSaA

Justin Shepherd · Answer

Get a scan tool with Live Data and find out what's wrong. Almost any basic scan tool will do the job. Cold engines need more fuel than air (running rich, it's a natural phenomenon). It gradually tapers to a to a perfect ratio of 14.7 parts air to 1 part fuel when it's at operating temperature. If it's easily accessible, try pulling and replacing the fuel filter.

Realize, when you're traveling with the engine at 3k RPMs and the engine is cold, you need 16x more fuel to do it vs an engine idling at 1,000 RPMs, plus some extra fuel, because it's cold.

You also need to adjust your valves.

Kaizen · Answer

Try letting the car warm up to operating temperature before driving. Look at your temperature gauge to help guide you.