question, car starts but doesn't fully start

[QueBert]

It's hard to explain. 2008 Saturn Sky Redline, had a key made for it today. It's been sitting for 4 months, so I would have normally chalked what it did up to it's been sitting a long time. But, it use to do it sporadically, like maybe once every 3-4 months. A few times it did it twice in the same day. After I'd drive off it ran great, I never noticed a drop in acceleration or anything.

Here what it does, I'll start the car and it appears to start normally but it'll struggle for a few seconds at the end. Not struggling like it's going to die, and it's fully turned over so it's not trying to start. It's like a hesitation right at the end. It's done this maybe 20 times in a year, and it's never died on me. I just wait 3-4 seconds and it goes back to normal. I'm not a car guy, my best guess is something to do with the fuel injectors but I'm probably way off. If anyone can understand how I'm explaining it and has an idea for me I'm all ears. I know it's something I need to get fixed, I'd like to do it on my own and I don't even know where to start.

 

[BonzaiDuck]

I came across a symptom like that, or a category of symptoms. Compared to my rides, yours is a recent model, but they made my Trooper with a lot of forward-thinking features.

I'm assuming your car has an Intake Air Temperature Sensor, or something like it. Does it have an idiot light in the instrument cluster that links to something like that? What about your "Check Engine" light?

Someone else could know better.

 

[QueBert]

I don't know for sure about the air intake temp sensor, but it has a turbo so that sounds like something it could have. I'm going to go Google that and see. No light on the dash is coming on. I'll probably get a good Bluetooth OBD2 scanner and maybe that'll turn up something.

Since it rarely happens I tend to just forget about it. but it could be something that turns into something serious. So I need to stop treating it like just an annoyance.

 

[RLGL]

ck fuel pressure

 

[JCH13]

Try turning the key "On" and giving it a few moments for the fuel system to prime up and other things to come online, then start it for real.

 

[EXCellR8]

Try turning the key "On" and giving it a few moments for the fuel system to prime up and other things to come online, then start it for real.

+1 I do this on the regular and rarely have problems. ON --> OFF --> ON --> START

Helps in the winter when your fuel pump gets sluggish...

OP I would certainly connect up a good OBDII scanner and see what the numbers are. I would also fill up with premium gas to see if that helps, though it doesn't quite sound like the actual fuel is to blame.

 

[Paperdoc]

I agree with JHC above. With most cars now the fuel pump is electric and mounted in the fuel tank. It pumps gas up to the fuel injector header, which has a small pressure bleed valve on the end to let excess gas flow back to the tank and regulate the pressure in the fuel header. Over a long period of non-use that header of fuel can slowly drain back to the tank. So when you first turn on the key after long downtime, it takes a few seconds for the pump to re-fill the fuel injector header completely so the engine gets what it needs. Unlesss you wait for that process, the engine gets little spurts of gas and nothing, making it hard to start. I think my son's 1999 Acura 1.6EL does this when the fuel tank is almost empty - the pump sucks some air at first.

To test this though, do what JHC13 said. Turn on the key and do NOT turn all the way to "start" for about 5 sec. THEN turn it. If that gets a fast clean start-up, this probably is your problem.

 

[ondma]

Could be a lot of things. Temperature sensor, throttle position sensor, weak/clogged injector or fuel filter, or as others have said, fuel pump.

+1 I do this on the regular and rarely have problems. ON --> OFF --> ON --> START

Helps in the winter when your fuel pump gets sluggish...

OP I would certainly connect up a good OBDII scanner and see what the numbers are. I would also fill up with premium gas to see if that helps, though it doesn't quite sound like the actual fuel is to blame.

Not sure I would recommend premium fuel for starting problems. I believe premium actually has a lower volatility than regular, so might make the car marginally harder to start. Also the OP should avoid the higher oxygenated fuels that are sometime sold with 15% or so ethanol. These can damage components in older cars like the one the OP has.

 

[RLGL]

Not sure I would recommend premium fuel for starting problems. I believe premium actually has a lower volatility than regular, so might make the car marginally harder to start. Also the OP should avoid the higher oxygenated fuels that are sometime sold with 15% or so ethanol. These can damage components in older cars like the one the OP has.

Premium fuel burns at a lower combustion temperature in a lower combustion ratio than it is designed for.

 

[QueBert]

thanks for the replies, since it happens so infrequently it'll be hard to know if the suggestions work. But, I'll half turn the key and let it prime for a few seconds before I start from now on. It sounds like this isn't something I need to stress over getting fixed. I thought it might be a sign of something bad to come.