Jeep cranks for 10 seconds

Will try testing again, I bought a new battery just to see if it would remedy my issue but I still had the same issue. Since then I returned the new battery since it did the same thing
If the cranking speed drops even with a new battery you have a bad battery cable or connector.

When the engine just plain won't start until after it has cranked considerably and this only happens at the first start of the day or when it has been sitting a considerable length of time, I'd suspect the fuel pump's check valve has gone bad and is leaking, allowing the gasoline that is supposed to stay in the fuel rail adjacent to the fuel injectors to instead drain out and back to the gas tank. The extended time to start is usually the amount of time required to get fuel back from the gas tank up to the fuel rail. If that's the case I'd replace the fuel pump. If you do end up doing that, avoid store brand fuel pumps. Not even if it comes with a "lifetime warranty" like Autozone provides for their Duralast parts... they seldom hold up. Bosch is the preferred brand but they're getting scarce. Delphi is a second-choice brand that generally receives good reviews. Again, don't install a store brand fuel pump, it won't last long enough to make it worth your time. Even if it does come with a lifetime warranty.
 
If the cranking speed drops even with a new battery you have a bad battery cable or connector.

When the engine just plain won't start until after it has cranked considerably and this only happens at the first start of the day or when it has been sitting a considerable length of time, I'd suspect the fuel pump's check valve has gone bad and is leaking, allowing the gasoline that is supposed to stay in the fuel rail adjacent to the fuel injectors to instead drain out and back to the gas tank. The extended time to start is usually the amount of time required to get fuel back from the gas tank up to the fuel rail. If that's the case I'd replace the fuel pump. If you do end up doing that, avoid store brand fuel pumps. Not even if it comes with a "lifetime warranty" like Autozone provides for their Duralast parts... they seldom hold up. Bosch is the preferred brand but they're getting scarce. Delphi is a second-choice brand that generally receives good reviews. Again, don't install a store brand fuel pump, it won't last long enough to make it worth your time. Even if it does come with a lifetime warranty.
I replaced my fuel pump with a Bosch a couple months ago when I was chasing a misfire…. Do you think I could have received a dud? I’m thinking I got a bad set of battery cables from custombatterycables.com. As for my P0340 code is that unrelated to my issue?
 
Yes you could have gotten a dud Bosch, maybe even a counterfeit.

Try this tomorrow morning before you try to start the engine. Cycle the ignition switch on-off-on ten times, pausing 2 seconds each time it's in the on position. That will give the fuel pump 20 seconds of extra run time to get fuel back up to the fuel rail. You can't just leave the ignition switch on for 20 seconds since the fuel pump automatically shuts off 1.8 seconds after the ignition switch is in the on position if the engine didn't start. If the engine starts right up after cycling the ignition switch 10 times it's like the fuel pump is bad.

It's unlikely to be a bad fuel pressure regulator. When that goes bad the engine won't start quickly even if it has been sitting just a few minutes.
 
The other thing about bad connections I preach is that the battery cables have 2 ends. A lot of people will clean the battery end and forget the end on the starter or ground connection. Seen a number of positive cables work loose on starters, or corroded ground connections cause problems.
 
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Yes you could have gotten a dud Bosch, maybe even a counterfeit.

Try this tomorrow morning before you try to start the engine. Cycle the ignition switch on-off-on ten times, pausing 2 seconds each time it's in the on position. That will give the fuel pump 20 seconds of extra run time to get fuel back up to the fuel rail. You can't just leave the ignition switch on for 20 seconds since the fuel pump automatically shuts off 1.8 seconds after the ignition switch is in the on position if the engine didn't start. If the engine starts right up after cycling the ignition switch 10 times it's like the fuel pump is bad.

It's unlikely to be a bad fuel pressure regulator. When that goes bad the engine won't start quickly even if it has been sitting just a few minutes.
Tried that this morning. It still did’t start. In fact this morning it didn’t start at all after multiple attempts. I don’t think it is related to my fuel pump but I won’t factor it out just yet. I saw this thread which seemed to be similar to mine. I ordered a new camshaft sensor and am crossing my fingers it solves my issue.
The other thing about bad connections I preach is that the battery cables have 2 ends. A lot of people will clean the battery end and forget the end on the starter or ground connection. Seen a number of positive cables work loose on starters, or corroded ground connections cause problems.
Good information. Though I’ve cleaned every end of my connections three times and made sure they are firm as can be. No corrosion either since they are newer cables
 
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