My 2001 XJ Sport (198k on it) has had, id say, a minor rough start when i got it back in Sept. You always have to crank it 2-3 times (figured it was fuel pump check valve or the fuel pump in general) and it would run a little rough for about 40-60 seconds and then smooth out, and get smoother as it got to temp. I FINALLY got a job thats about a 40 min drive from my house. So i have been making that trip this past Tuesday through Friday. I noticed yesterday that when i started it (2 cranks) it seemed rougher than before. it almost slowed down to a stall, but didnt and it seemed to run rough for at least 2-3 minutes, but again once close to temp, it smoothed out. I havent done any work to it since i got it aside from changing the rear wheel bearings and seals and chaging the rear EVAP line between the fuel tank and canister to a rubber line. I am an amatuer at best with fixing cars. Does this seem like a "change the plugs and clean out the throttle body" thing or something more involved? I am a little concerned about changing the plugs cuz im afraid i may damage the plug on the back of the coil pack and then not be able to get to work. *yeesh*

it has a TUPY head, id assume swapped by a previous owner. I dont smell any fuel under the hood. Everything looks dry, so i dont see any obvious fuel line leaks/issues. It has an EVAP "Large leak" code, and Running rich codes. I dont smell fuel or any strong smells when its running, so according to a mechanic freind of mine (he lives in PA im in NY so he cant just come and look at this) its likely not running rich and just needs new sensors.

In hindsight, this may have not been the best choice of vehicle to commute with lol I loved the 88 i had in 2004, so thats why i went this route. I was hoping to find work much closer, but this was a good opportunity and finances were way in the red, so i had to take this job. I ant to get this running well though and fix the EVAP and running rich codes and the pinion since it sounds like a skateboarder going down a hill and then i will likely sell the XJ and find another car. But for now i want to get this running correctly and be a reliable as an XJ could be lol

 

I have the same symptoms on start up on a 2001 XJ (takes a lot of cranking). Check valve for fuel line just arrived in the mail. Some say don't use it on 1997 and newer Cherokee or fuel line will burst. Supposedly becomes fuel system has not return line. I have my doubts about that claim. I'm going to try and install it this week.