Starting A Car That Has Sit For A Year - Any Tips

Mar 17, 2011
I have a 2004 Nissan Sentra 1.8.
I had alternator/charging issues about a year ago and parked it here in Florida with about a half tank of regular 87 fuel.
I had been called out on several long projects since then, been sidetracked with other projects and the vehicle has been sitting and has not even been started since then.
I am concerned to just try to start it after sitting so long for fear that the fuel has gone bad and don't want to risk damaging other components in the engine/fuel system.
In my boat, I use ethanol free fuel with QuickCare additive and never had an issue, even after it sits for months, but that is not the case with the Nissan.

Do you think there could be any problem with the fuel that would warrant the time and effort to drain the tank...and dispose of the old fuel, or is there some additive I could add prior to starting it for the first time?
I have a pump that I used to drain, filter and inspect my boat tank, perhaps I could take that approach again and run a scope into the empty tank to inspect it.

Any advice?
If you are invested in the ride, remove the fuel (i think you can siphon from the filler or underneath the rear seat bottom).
Make sure there aren't mouse nests in the air intake then hit it!

The EVAP system on modern cars keeps the volatiles in gas, in the tank where they belong.

I don't know your car in particular but many have a fuel pressure test port on the rail near the injectors. You can prime the system by turning the key on but not starting it, then pressing down on the schraeder pin to vent some gas. If it smells like gas, not varnish, it's good to go.
Charge the battery first, if you can, connect another charged battery via jumper cables (the larger the battery the better). Do not have the vehicle the other battery is in running if it is in a vehicle (there is a slight chance of damaging the alternator of the good vehicle if you run the engine while another vehicle cranks). Sometimes a sitting engine will get some rust in the cylinders, and having another battery will keep the voltage up while the starter works against this extra load for a start after a long time sitting. This problem is not as common as it used to be. But if a good battery is available, it does not hurt to add its power via some jumper cables, and it might help. It is easier on the starter to keep the voltage up and start it faster, than to crank it slow and take longer to start because the spark is weak because the voltage of the battery went too low because it was supplying greater than normal amount of current.
FWIW, I would charge the battery, check tire pressures, oil level and air filter to make sure everything is in good order. Then I would start it up and drive to a gas station to put some fresh fuel in. Take it for a good highway drive and get it up to operating temp. If you want to then change the oil, done.

Just my $0.02
I think gasoline should still be OK even after a year. However, before starting the engine, remove the fuel fill cap and take a whiff. I don't know what ethanol blended gasoline smells like when they turn sour, but straight gasoline smells like turpentine when it turn bad.
i would run it. I've started plenty of cars on 5 year old gas. EFI isn't as picky as carburetors and one you get fresh gas in it it'll be fine.
My mother splits her time between two states; Minnesota in the summer months and Houston the rest of the year. Due to covid, she didn't return to Minnesota between September 2019 and June 2021. Her 2009 Chrysler minivan was not run for 20 months. It had a battery tender attached the entire time. Mom removed the tender and it started right up. The first thing she did was bring it to a shop for an oil change and other maintenance. The mechanic laughed because it had less than 60 miles since the previous oil change!

My advice is to just check the tires, battery, etc. Then start it and don't look back. Some people overthink this stuff.
It will be fine. One year is nothing on an EFI engine. If you want to go the extra mile remove the spark plugs and spray each cylinder with a quick shot of some light lubricant to give the rings a bit of oil. Charge it and fire it up!

Go get a bottle of Gumout w/Regane fuel system cleaner and top off the tank with some good gas. Change the oil and drive it like you stole it for the first tank of gas!

I let my 1987 4Runner w/22RE sit for 7 years. Took about 5-10 seconds for the fuel to make it to the injectors but fired right up and ran like I parked it yesterday.