hi, i have a 89 xj 4.0l auto 4x4 with a start problem! it wont crank with the key but i can hook up a wire from the solinoid to the baterys and it cranks but it wont fire! one day i was driveing and it wa bads cuting out really bad well drove it home and parked it, then i went to start it the next morning it would crank but not fire!so i figured fuel pump so i checked fuel pressue and it was about 35psi! then i figured CPS and replaced it and distributor pickup, cap and rotor, plug wires, and spark plugs, coil, and the starter relay, also the ignition swich (not the key swich) now when you turn the key on the fuel pump or latch relay chaters i replaced the relays still does the same thing! but whil it chaters i get no spark at the coil, but if i pull the relay it gets spark but no fuel! also it i disconect the fuel pump it dont chater but i still get not spark! the only think i can think next it the pcm?

 

check the resistor on the driverside inner fender, its just a little bar with two wires bolted to it. Just pull the wires and conect them. If that does it replace the resistor and keep a spare, they go bad all the time.

 

Sounds like a neutral safety switch, although i don't know if your xjs have that problem try starting your truck in neutral. Mind you this would only temp fix the problem. Only if you turn the key to start and nothing happens, but you should have battery power. Try wiggling the shifter while holding the key to start.
If you know about nss problems just ignore this reply.

 

It IS the neutral safety switch

My brother JUST had the same problem with his....

 

you say your brother had the same problem! so like he was only getting fuel (not spark) but when he removed the relay he would get spark but no fuel and he was getting relay chatter out of the B+ relay?

 

Sounds like what happen to my and we found a broken ground by a sensor. Check all of your grounds.

 

crank sensor

 

ok i have out a new pcm in it still nothing and i decovered that the fuel pump relay is the one that chatters but only when the fuel pump is plugged in and it has a new cps

 

Here is a great info to fix the NSS. XJ's have alot of gunk of in them and the fix is easy. And by cleaning the contacts you can rule out a common problem that may solve your issues.
http://jeepin.com/features/nss/


This link is also good on fixing it
http://www.cherokee-jeep.com/1-2swremov.htm

Good Luck.

 

ok did the neutral safty switch and still not fixed but its the fuels pumnp relay that is chattering when the key is on! but i still get fuel pressuare just no spark but if i pull out the relay then i loose fuel pressure (duh right lol) but i get spark? wth