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Engine stumbles at startup after truck sits for a while

Quickstep192

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I’ve noticed lately, that my gladiator engine stumbles after starting after the truck has been sitting for a week or two.

I have to nurse the gas a little to keep it running, but after that it seems fine.

Has anyone else experienced this and knows the cause and cure?
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Hootbro

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Bad gas, old gas? How many miles on it?

I would fill the tank with fresh Tier 1 non ethanol gas (if you can find it) and run a bottle of Techron Fuel Cleaner before getting too deep into it.
 

1Badazraptor

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I'm not a certified mechanic but I have owned a lot of used vehicles, I would first clean the mass air flow sensor.
 

Noeyes

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Bad gas, old gas? How many miles on it?

I would fill the tank with fresh Tier 1 non ethanol gas (if you can find it) and run a bottle of Techron Fuel Cleaner before getting too deep into it.
My thought too. Bad or old gas.
 

Splenda

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I only drive about 600 miles a month, and it usually sits all weekend. It doesn't sit because I drive another vehicle instead. It sits because it's not uncommon for me to get home from work on Friday evening and not go anywhere until I leave for work on Monday morning. I find that mine runs a little rough on Monday morning startup, and I suspect it's the battery. Evidently, short trips are not enough to keep the battery topped up, and after a few weeks, my battery is usually at about 70% charge. Putting it on a slow charger every few weeks has kept it charged and running smoothly. This may not be the cause for you, but just a thought.
 

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Quickstep192

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The last time it happened i had filled up with fresh gas on Friday and it sat until Tuesday.
 

ShadowsPapa

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The last time it happened i had filled up with fresh gas on Friday and it sat until Tuesday.
Mine can sit from Saturday until the next Wednesday or Thursday.
I run U88 - which is 15% ethanol.
Zero troubles.
In fact, all 3 of my Gladiators have run at least 10% and often 15%, and often sat with some days in between drives.
No issues.
(thinking back, my wife's Grand Cherokees with the 3.6 might sit a week or longer and not have any problems other than the batteries being low from sitting so long)
 

Maverickxeo

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I've had that happen twice to me - completely randomly on a cold start, but it didn't sit longer than overnight each time. I have 50k KM on it, and no issues, codes, etc. Not sure what caused it in my case, but hoping to see some feedback here.
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