Coil pack going bad?

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2003 Buick Century 3.1L Here lately ive noticed that first starting the car after a few days without running, the car is temperamental about starting. By that I mean it takes two or three tries to get it started. The engine turns over just fine, but it doesn't actually start until mostly the 3rd and sometimes 4th try. The motor was replaced about a year ago(used of course) just after I got the car and it was starting just fine at the time. Battery was replaced at the same time. Is this a coil pack going bad? Thanks guys,
 
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If it is only after sitting for a couple days, I would think the fuel pressure is not being maintained in the system when off. Could be a bad check valve in the fuel pump assembly. Try turning the key to the on position a couple times before starting to let the fuel system prime.
 

NavyVet88

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Originally Posted By: mightymousetech
If it is only after sitting for a couple days, I would think the fuel pressure is not being maintained in the system when off. Could be a bad check valve in the fuel pump assembly. Try turning the key to the on position a couple times before starting to let the fuel system prime.
Well the car only gets driven a couple times a week for groceries and such or quick errands. I failed to mention in my opening post that once the engine does start, it struggles to get going unless you press the gas pedal a bit to help it.
 
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Originally Posted By: NavyVet88
Originally Posted By: mightymousetech
If it is only after sitting for a couple days, I would think the fuel pressure is not being maintained in the system when off. Could be a bad check valve in the fuel pump assembly. Try turning the key to the on position a couple times before starting to let the fuel system prime.
Well the car only gets driven a couple times a week for groceries and such or quick errands. I failed to mention in my opening post that once the engine does start, it struggles to get going unless you press the gas pedal a bit to help it.
Could be just plugs. When were they replaced last?
 
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NavyVet88

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Originally Posted By: mightymousetech
Originally Posted By: NavyVet88
Originally Posted By: mightymousetech
If it is only after sitting for a couple days, I would think the fuel pressure is not being maintained in the system when off. Could be a bad check valve in the fuel pump assembly. Try turning the key to the on position a couple times before starting to let the fuel system prime.
About 6 months ago. Oem plugs to boot. Well the car only gets driven a couple times a week for groceries and such or quick errands. I failed to mention in my opening post that once the engine does start, it struggles to get going unless you press the gas pedal a bit to help it.
Could be just plugs. When were they replaced last?
About 6 months ago. With oem plugs.
 
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Originally Posted By: mightymousetech
Originally Posted By: NavyVet88
[quote=mightymousetech]If it is only after sitting for a couple days, I would think the fuel pressure is not being maintained in the system when off. Could be a bad check valve in the fuel pump assembly. Try turning the key to the on position a couple times before starting to let the fuel system prime.
Well the car only gets driven a couple times a week for groceries and such or quick errands. I failed to mention in my opening post that once the engine does start, it struggles to get going unless you press the gas pedal a bit to help it.
I have a feeling that you most likely have a leaking fuel pressure regulator on the fuel rail, this is a fairly common problem on these engines and is easily diagnosed - remove the vacuum hose going to it on the fuel rail and inspect for any raw fuel vapors / liquid coming out of the regulator ( or filling the vac. line, if failed bad enough ) Just key up the vehicle ignition, ( cycle on but don't start car ) a few times after sitting ( for a bit ) with the vacuum line off... any liquid fuel that comes out and it is automatically a failed part. The result of this is hard starting as it is too rich from the leaking fuel from the regulator, causing a hard start. I would put a large bet on this being your failure, esp. at the miles accrued and if it never has been replaced before... BurrWinder
 

NavyVet88

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Originally Posted By: BurrWinder
Originally Posted By: mightymousetech
Originally Posted By: NavyVet88
[quote=mightymousetech]If it is only after sitting for a couple days, I would think the fuel pressure is not being maintained in the system when off. Could be a bad check valve in the fuel pump assembly. Try turning the key to the on position a couple times before starting to let the fuel system prime.
Well the car only gets driven a couple times a week for groceries and such or quick errands. I failed to mention in my opening post that once the engine does start, it struggles to get going unless you press the gas pedal a bit to help it.
I have a feeling that you most likely have a leaking fuel pressure regulator on the fuel rail, this is a fairly common problem on these engines and is easily diagnosed - remove the vacuum hose going to it on the fuel rail and inspect for any raw fuel vapors / liquid coming out of the regulator ( or filling the vac. line, if failed bad enough ) Just key up the vehicle ignition, ( cycle on but don't start car ) a few times after sitting ( for a bit ) with the vacuum line off... any liquid fuel that comes out and it is automatically a failed part. The result of this is hard starting as it is too rich from the leaking fuel from the regulator, causing a hard start. I would put a large bet on this being your failure, esp. at the miles accrued and if it never has been replaced before... BurrWinder
Thank you sir I will check this this weekend when off work.
 

CT8

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Originally Posted By: mightymousetech
If it is only after sitting for a couple days, I would think the fuel pressure is not being maintained in the system when off. Could be a bad check valve in the fuel pump assembly. Try turning the key to the on position a couple times before starting to let the fuel system prime.
This is where to start trouble shooting.
 
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Originally Posted By: NavyVet88
2003 Buick Century 3.1L Here lately ive noticed that first starting the car after a few days without running, the car is temperamental about starting. By that I mean it takes two or three tries to get it started. The engine turns over just fine, but it doesn't actually start until mostly the 3rd and sometimes 4th try. The motor was replaced about a year ago(used of course) just after I got the car and it was starting just fine at the time. Battery was replaced at the same time. Is this a coil pack going bad? Thanks guys,
How old do you think those sparkplugs in the used engine were? Maybe pull and plug and have a look. Spark plug wires also eventually should be changed. Spray a bit of water on the coil pack to see if there are cracks in the coil pack that you might be able to short out as evidence of a problem.
 
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Hi Your didn't say what car ~ how many miles ~ of if it's nice and wet ~ where your car is sitting ~ I would say spark plug cables ~ clean and dry you distributor ``` It could be any ~ and all ~ that has been mentioned ``` Can you pull a plug ~ and see if you'r getting spark ~ some cars~ it's tough to get to the plugs ~ we know ``` Tell us a little more ~ as well as what you've done so far ~ if anything ``
 
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Most coil sales go to people with an incorrect diagnosis. They rarely just sort of work. It’s either obvious by looks or feel. Check the boots. That’s free. If you find a rotted or burned that’s a good reason to change. Otherwise it’s just $$ in the parts store pockets
 
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Originally Posted By: 2strokeNorthstar
Most coil sales go to people with an incorrect diagnosis. They rarely just sort of work. It’s either obvious by looks or feel. Check the boots. That’s free. If you find a rotted or burned that’s a good reason to change. Otherwise it’s just $$ in the parts store pockets
My camry coil-on-plugs die slowly-- first leaving me with a lurch when I go from off-the-gas to on-the-gas. Finally they get bad enough to throw a code. One went from mediocre to off-like-a-light-bulb. However OPs car should start on 4-5 cylinders. Agree with the fuel problem.
 

NavyVet88

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I plan on giving this a go with the fuel pressure regulator this weekend if nothing else comes up. the spark plugs were changed about 6 months ago with brand new oem plugs
 
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Classic low fuel pressure symptoms. It's highly unlikely that plugs, coil, throttle body, etc would cause this issue.
 
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