My 98 Neon has been inconsistent when starting since I bought it a year and a half ago, with 65.5k miles. Sometimes it cranks for a long time, sometimes it turns over right away. 100 degrees or below zero, same story. If it’s sat for a long time, it generally takes longer. And sometimes, when it’s been cranking for a long time (5 seconds+), I let up on starting and it kinda sputters a little like it’s trying to turn over, then it either turns over or dies. Also, tends to take a lot longer when I have less than half a tank of gas.
It has 73.5k on it right now. Major transmission service 7k ago, got a new battery 5k ago, new plugs & air filter .5k ago, and oil changes every 3k-4k miles.
I’ve done my research, and I’ve seen two possible issues that could cause this. The most popular one is a bad starter. The other less popular one is a faulty/bad check valve in the fuel pump assembly that lets fuel back into the gas tank when I turn it off. Seeing as how sometimes my car sputters like it’s running out of gas just before turning over, and how it’s faster to turn over when I have more than half a tank of gas, I’m gonna say it’s not the starter.
So, my question is this: If it’s the check valve, will I have to replace the whole fuel pump assembly or just one part of it, like the pump or the fuel pressure regulator. Or, is it something completely different?
I would have the ignition coil checked. These cars were infamous for weak ignition coils. Its easy to test by checking the primary, and secondary resistance with a ohm meter to see if its within spec. The Haynes manual has the procedure, and the resistance specification if you want to try and check the coil yourself.
If you conclude the problem is with fuel delivery, you will need to replace the fuel pump. The pump and check valve are all one single unit. It’s not a bad DIY job if you are so inclined, since you don’t have to drop the tank. Access is from underneath the car and there is a drain to remove remaining fuel.