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Hard start when cold?

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Old Mar 9, 2018 | 10:11 PM
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Default Hard start when cold?

04 z06 23k miles stock

started it this morning in the garage and it cranked a good 5 secs then started rough and quickly idled fine.

pulled out of garage let it run for a minute then turned off. Started fine right after that.

go to work let it sit for a few hours then another rough start.

thinking maybe the battery I bought a new one and no help.

any idea what could be going on?

the reserve gas light came on and about 1/8 tank just touching the red.

no check engine light other than check gauges which I assume is the reserve fuel notification.

drives perfectly fine

Last edited by jehovasfitness; Mar 9, 2018 at 10:12 PM.
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Old Mar 10, 2018 | 07:27 AM
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Your comment about the fuel level is a good one. You may want to try putting some dry gas treatment into the tank and filling it up. It could be you have water or other crap in the tank
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Old Mar 10, 2018 | 07:53 AM
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After some research I did 3 things.

1. Cycled key on/off 5x

2. Gave the throttle a little help

3. Random thing upon my own inkling and used the spare key.

Started fine. Now I gotta do one at a time and see which if any helps
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Old Mar 10, 2018 | 12:19 PM
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Originally Posted by jehovasfitness
04 z06 23k miles stock

started it this morning in the garage and it cranked a good 5 secs then started rough and quickly idled fine.

pulled out of garage let it run for a minute then turned off. Started fine right after that.

go to work let it sit for a few hours then another rough start.

thinking maybe the battery I bought a new one and no help.

any idea what could be going on?

the reserve gas light came on and about 1/8 tank just touching the red.

no check engine light other than check gauges which I assume is the reserve fuel notification.

drives perfectly fine
My z did the same thing..i replaced the battery and put a tender on it..never had the problem again. Or fuel pressure problem
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Old Mar 10, 2018 | 12:50 PM
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Bad gas maybe?
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Old Mar 10, 2018 | 01:20 PM
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Gas was only few weeks old and kept in garage
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Old Mar 10, 2018 | 02:28 PM
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Is it your dd? If not use a battery tender.

Last edited by 04zjimc; Mar 10, 2018 at 02:32 PM.
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Old Mar 10, 2018 | 02:33 PM
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Originally Posted by 3sACROWD
Your comment about the fuel level is a good one. You may want to try putting some dry gas treatment into the tank and filling it up. It could be you have water or other crap in the tank
What fuel do you use?
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Old Mar 10, 2018 | 03:27 PM
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Shell 93 octane

let it sit to cooldown and tried to start normal and it struggled again. Next step using the give it some gas pedal assistance
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Old Mar 10, 2018 | 04:51 PM
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Tried to give it some throttle and no help

got home shut it off and tried to restart it immediately and it started fine
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Old Mar 10, 2018 | 05:07 PM
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Originally Posted by jehovasfitness
Tried to give it some throttle and no help

got home shut it off and tried to restart it immediately and it started fine
Check fuel pressure
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Old Mar 10, 2018 | 05:55 PM
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Originally Posted by 04zjimc
Check fuel pressure
thanks and that's what I was thinking based upon the symptoms.
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Old Mar 12, 2018 | 12:33 PM
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Took it to a shop and they said it was a bad fuel injector. Going to replace all of them, as it's not that much more.

Figured the car is 14 yrs old, but only has 23k miles. Ugh
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Old Mar 13, 2018 | 10:24 PM
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Update: one bad fuel injector and replaced them all

starts and runs great. I didn' even realize driving was subpar as well but now great
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Old Mar 14, 2018 | 05:14 AM
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Originally Posted by jehovasfitness
Update: one bad fuel injector and replaced them all

starts and runs great. I didn' even realize driving was subpar as well but now great
Good to hear
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