Hi everyone this is my first post on here. I recently bought a 97 Cherokee Sport 4.0 and when its cold out it cranks for atleast 5 seconds before it'll start and then it idles at about 500 rpm till its warm. I recently replaced the fuel pump because it had the common bad check valve issue, i also put in a brand new battery with 800 cca's, i did new plugs, wires, cap and rotor. Right before i bought it the previous owner did a crank position sensor. Once its warm it runs awesome and if i shut it off then go into a store and come back out it starts on the first crank. Any ideas? Oh and It only has 112,000 miles. Ive owed a 94, 95 and 96 Cherokee 4.0 before and never have had this issue before.

 

What kind of shape is the cable from BAT+ to the STARTER?

 

What brand fuel pump did you install?

Did you replace the entire assembly or just the pump? The reason I'm asking this is that there are 2 check valves. The primary one is on the regulator, the secondary one is on the pump.

 

I would put a fuel pressure gauge on it and make sure it holds pressure after shutdown.

 

I put in a Carter and i did the entire assembly. Before i did the swap i would cycle the key on and off a couple times then it would run like crap for the first couple mins all the time even if the jeep was still warm. Now it only cranks long when its cold and then idles at 500-600 rpm until its warm and then it runs awesome. If its already warm it'll start first crank so i believe its holding pressure fine.