2007 Chevrolet Cobalt - is it a starter problem?

chevrolet
cobalt

#1

As of about a week ago my Cobalt has developed a starting problem. It still starts, but has to crank for roughly 5 seconds before the engine turns over. There are no strange noises, only a prolonged cranking period. Once running, for even a few seconds, I can shut off the engine and every subsequent start is normal unless the car sits for an hour or so. Does this sound like a classic starter problem? I’ve read that a bad electrical connection can also cause starting issues, but don’t think any other part is complex enough to behave like this (i.e. function normally when “hot”.) BTW, my car is a manual transmission, and I had the ignition switch replaced not too many years ago as part of the infamous Cobalt ignition switch/airbag recall.

Should I just jump in replace the starter or is it worth looking elsewhere first? I am mechanically inclined but this is my first time troubleshooting a starter problem. Thanks!


#2

No, not at all, The starter spins the engine so the starter is fine.

You don’t say how many miles are on the engine but this is typical of a leaking fuel injector or a fuel pump check valve. The car won’t hold pressure in the fuel rail overnight. Next time you start the car for the first time that day, turn the key to the ON position but not start. You should hear the hum of the fuel pump. Turn it back off and then back ON about 3-4 times. Then turn it to crank. If it fires right up one of those 2 issues is your problem. If the car is otherwise running well with no stumbles or misfires, it is the fuel pump.

As long as it starts up and runs, I wouldn’t do more than maybe run a bottle of fuel injector cleaner through the tank for now. When it gets harder and harder to start, change the fuel pump.


#3

Hey, thanks! Will test this tonight or tomorrow. You’ve saved me ~$150…until the fuel pump issue looms too large.

BTW, the car has about 145K miles on it, so there’s definitely some wear and tear. It’s mostly highway miles, but probably not relevant to this case.


#4

If the “key dance” Mustangman describes works and everyone who drives the car knows it, you may go for years without the problem getting any worse. On my 1999 Civic the problem seems to occur with a low fuel level in the tank, and even then rarely.

What happens with every On-Off turn of the key is that the fuel pump runs for a couple seconds in the On position. You may hear it. Turning the key to Off and back to On energizes the fuel pump for a couple more seconds. Fuel and fuel pressure are brought up to the engine. When you finally turn the key to Start, it starts.


#5

Even further evidence of a fuel pump. I think this car has an access plate for the pump under the back seat. That allows you to change it without dropping the tank… 'cause you just KNOW it will finally fail with a full tank! Murphy’s Law! :wink:


#6

Yes, it’s definitely fuel line-related. Turning the ignition switch to “on” a couple times does let the engine crank and start normally. Thanks for all the tips.

But I’m not sure it’s the fuel pump because I’ve started noticing a faint odor of gas fumes around the car. I assume the lack of pressure in the fuel line could come from anywhere in the system. I normally park outside and it’s been raining a lot lately, but this weekend am thinking about putting it in a well-ventilated garage with cardboard or something else underneath to look for drips. Unless you can think of a better method?

And if that leads nowhere, I’ll just take it to my local garage and have them check the lines. At least it won’t be a $500+ fuel pump job…which per some YouTube videos IS in the tank. I was initially relieved that it wasn’t a starter issue, as this brought back memories of the tiny, external fuel pumps on my older cars. But now I’m feeling a little relief again. I hope.


#7

Sounds like a fuel leak = probably quickly located by a careful mechanic with a hydrocarbon sniffer. Good luck.