My 99 XJ is an automatic trans, and for the last 2 months or so its been shutting off at idle. been able to keep it alive at stop lights by holding the rpms at about 1500 and holding the brakes. now its getting worse, its to the point where after it warms up if i shift from D to R or vise versa it likes to shut off. after it does this i have to crank it with a full throttle to get it to start, sometimes its revving rough and have to hold foot to floor for a few moments to keep it alive.

HERES WHAT IVE REPLACED (note everything ive replaced so far has been brand new)
Fuel pump and pressure regulator since it a combo for my year xj
fuel rail
injector for cylinder 1 (had one laying around from when cylinder 1 would missfire so threw it in when replacing fuel rail)
crank shaft position sensor
top O2 sensor (just today)
and my mechanic had found water/algae growing in the plugs to ecu, they cleaned it but found no other issue

when it was at the mechanic they check the distributor and cam sensor both are good, its only been a week since it was there so i dont think they have gone bad in this short amount of time

at this point im running out of things i can think of to solve my issue, any suggestions. im off of work for three days straight so im gonna be thinkering with it, planning on cleaning the IAC sensor