Had this xj for over a year now as my daily driver. It is a 4.0 in-line 6 engine with 4wd.
This summer I have encountered a stalling problem: it runs well while driving, no problem, but as soon as I decelerate to a stop (in drive, foot on brake, such as a red light or stop sign), it will stall out. 75% of the time it will start right back up, and 25% it will not. The engine kicks/turns over fine, and I have full power from the battery, but I cannot get spark. I will wait 20 min or so and it will start up again. My temp gauge also reads normal, so I know the engine is not overheating.
Stall is also triggered sometimes when hitting a speed bump or train tracks, but if I punch the gas at the same time as hitting the bump, it will not stall. I have also figured out a trick for red lights: if I put it in Park and continue to give it it gas, it will not stall.
I have replaced the fuel pump and the fuel filter last week, IAC is brand new, and my engine is brand new as of last summer.
Sometimes when I haven’t been driving it, and I try to start it mid-day, it will not start up (same as before, The engine kicks/turns over fine, and I have full power from the battery, but I cannot get spark). I have pondered the possibility of “heat soak” causing my fuel injectors to seize up, because it is common in the 4.0 xj, and because it seems to worsen during peak heat (95 degrees). But, I have never heard of heat soak causing so many problems.
Any thoughts would be helpful!