Heres the basics, After putting cheap gas in it I have very rough idle in all gears at about 700-
Could be a lot of things, first thing I'd try is replace the fuel filter, where that is depends on the year of the car, next check the injectors, if it's LH-Jet you can remove the whole fuel rail, unplug 3 of the injectors and point the connected one into a jar while someone cranks the engine. Check all 4 and look at the spray pattern.
Bad gas usually won't hurt the injectors. If its truly bad gas, then there is probably water in it and you need to remove it with some non-alcohol-based product.
Cheapest and easiest thing to do is to first follow Fred Flinstone's suggestion and use some "Redline Water Remover and Antifreeze."
Removing ALL the gas by hand from the tank could be next if first suggestion doesn't work.
Next stop might be to replace the fuel filter. But it wasn't necessary in my case.
Have something to add? Share your thoughts — no account required.
Ask the community — no account required