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Discussion Starter #1
So I'm having trouble with my engine starting every now and then. It only seems to do this when the engine is hot. For example, I'll go run some errands and once I've made a few stops, the engine will turn over, but take an extra 5 seconds or so to stop. In the mornings or if I haven't driven in a few hours it starts just fine.
 

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I think I have this same issue- you go drive around, stop to get gas for example, then after you fill up (engine is warm at this point) it turns over but doesn't start right away, right ? I saw someone on this forum once reference the fact that these cars have an issue with the air/fuel ratio needed to ignite the engine, and since it's controlled by a computer, sometimes the comp's readings are off, and it automatically prevents the engine from starting. It was something along those lines but don't take my word as Gospel, so to speak. That, and of course make sure your battery/plugs are in good shape.
 

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This is also a common problem if your battery is going bad, it seems like. When the battery is bad your starter will not output as much power, which leads to slower cranking speed. There is a reason an engine idles at 7-800rpms and not 200, at 200 it would not have the torque to keep it self turning. You get what I'm saying? I had this problem, but as soon as I replaced my bad battery it was all good.

Of course, there are other things that can affect it, such as a bad IAC (Idle Air Control) valve. Mine went bad not long ago, and it would crank forever before the engine fired up because the IAC had stuck closed (I had to put my foot on the gas pedal to get enough air in).
 

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I had the same problem when I first got my car and i have only had a month or so now. I read a post about it and the type of fuel and oct being used. should we use regular or super. most posts leaned to the better gas. I started using the super or 92 oct and have not had the starting issue.

My car was garaged most of the time before I bought it now its a dd so maybe it just needed to be used and cleaned out.
 

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I had the same problem when I first got my car and i have only had a month or so now. I read a post about it and the type of fuel and oct being used. should we use regular or super. most posts leaned to the better gas. I started using the super or 92 oct and have not had the starting issue.

My car was garaged most of the time before I bought it now its a dd so maybe it just needed to be used and cleaned out.
The octane rating will have no effect on this, what so ever. What will affect this, though, is the amount of ethanol and other additives. A good brand of 87 octane gasoline (for example Shell) is definitely to prefer over a ghetto-brand 87 octane. It is very hard to find places that sells pure 87 octane gas, just about all of them add up to 10% ethanol in it, while some add even more. From what I have heard and read Shell, Statoil and Chevron seem to be among the best. Generally you should be more than fine by just avoiding off-brand names and ghetto places.

Dataken: If your car was garaged most of the time before you bought it, the gas might have started going stale. You may start noticing a difference in performance after just a few weeks of not driving. A few tanks of gas with some fuel system cleaner or seafoam generally does the trick. Also, I might add that if condensation builds up in the gas tank that will cause problems too.
 

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Yes I like to use chevron or shell as well. 76 use to be great but they are hard to find around here.

I use to work at a mobile when i was younger and my friend had a 1965 mustang built engine 351 w he put gas in it at my work and it just died lol.

I agree dont buy cheap gas. So I dont know if it was the better gas that helped mine but it did stop.
 

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Yes I like to use chevron or shell as well. 76 use to be great but they are hard to find around here.

I use to work at a mobile when i was younger and my friend had a 1965 mustang built engine 351 w he put gas in it at my work and it just died lol.

I agree dont buy cheap gas. So I dont know if it was the better gas that helped mine but it did stop.
I recently had mine in storage for two years (I did start it up and drive it every 6 months). I always unhooked the battery and added fuel stabilizer to a full tank of gas before putting it away. I would usually have to run through about 2 full tanks of gas before it would be back to normal, even after just 6 months in storage.

You don't have to buy the most expensive gas, but don't go too cheap either. I usually fill at a local Pilot or Racetrac station, as they are the ones I drive by every day. Sadly I do not have a Shell station nearby, but Pilot and Racetrac are really nice and have "medium" quality gas, which is more than good enough for daily driving in our 4.6's. If you are supercharged or have the car tuned for track performance on the other hand, then you are more limited to what quality gas to get. Also, if the car is tuned for 91 or 92, do NOT use 87 as you WILL experience knock, but that's a whole different topic.
 

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Discussion Starter #9
I recently replaced the battery (about 3 weeks ago) so I hope it's not a battery problem again. I don't have any codes either. The IAC would trip the light though, wouldn't it?
 

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The IAC did not trip the light with me. If the IAC is bad you would most likely also have a poor, uneven idle, more jerky initial acceleration, and the engine may stall out sometimes at idle. Have you checked your alternator? If you have a voltmeter check that you have between 13.5-14.0 volts by the battery terminals while the car is running. Because it is a new battery you should have between 12.5-13.0 at the battery when the car is off, but you are good as long as it is at least 12.0 volts.

When did this problem start occurring?
 

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Discussion Starter #11
If I can get ahold of a voltmeter if I can. I haven't had any problems with idling, acceleration, or engine stalling at idle. This has been happening for the past few months. I've had it since May and it's been doing it since then. Not always, just if I run it a lot.
 
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