2 Cherokee's w/2 different problems

Ok, I have searched both topics and have yet to find a good answer.

First my 97 4.0 with 178k miles drives great most of the time and gets 15-17MPG.
Lately it just all of the sudden dies while driving? Sometimes it dies completely and then re-starts after multiple cranks and then sometimes it just sputters and loses power and RPM but stays running like I shut the key off and turned it back on right away. Along with that I was coming back from a 4 hr roadtrip this weekend when the temp guage went down to 100 and the check engine light came on. It stayed low until I accelerated hard and then it jumped back up for a while until I stopped at a gas station then the guage started bouncing around and it started idling high. Drove it a few more miles and then the temp stayed good the rest of the trip?(new thermostat and temp sending unit last year) Recent tune-up also.????

Second is an issue with my 2000 4.0 90k miles I recently bought. It would crank for 5-7 seconds and then fire so I put in a new fuel pump and filters. Started great the first couple of times after putting it in and then now it still does it. I gave it a good tune-up the other day and still same thing. Also it sputters a bit upon first starting and then smoothes out. It is all stock and I am only getting 14-15 MPG in the city. I found a ton of threads on this but none of them ever gave a fix whether it be a feul injector or a valve in the pump?
Help please.

This is little and probably not it, but is the fuel filter installed with the arrow facing towards the front of the jeep.

Like I said it probably isn't it, but it's worth a thought at least. Good luck!

I put it in correctly for sure.

Thanks

Any other helpful advise?

On my 98 I had the wiring harness wear through between the fuel rail and the firewall. This lead to the temp guage jumping around giving false readings, and making the engine run rich and take out my O2 sensor, causing running problems, idle problems, etc.

Point being, maybe check your wiring and remember it could be multiple things causing it.

97+ don't have an external fuel filter.

97, I would look for loose wires, or a coolant leak near and on a sensitive part like the TPS or wires.

Also check the O2 sensors and their wiring near the exhaust pipes.

Thanks for the help, I will keep investigating. Who said 97+ has an external filter Blaine B?

4LowandGo mentioned to check to make sure the arrow on the fuel filter was pointing the front of the Jeep.

But since there is no external filter you won't have to worry about that. That is the post I was replying to when I posted.