Hi, I have a 96zj I am working on with a 5.2 v8 that will not start, Checking the voltage on the injectors I found that I have excellent ground on all the injectors, but while cranking I am only getting 9-10v on the positive side (in my case green wire) on the injector, Is that enough voltage to operate the injector or do I have a pcm/voltage regulator problem. Thanks in advanced for any help,

 

Also The jeep has fuel to the rail, and it has spark at the plugs, but no fire.

 

It says to check for battery voltage at the voltage supply wire which is usually green and is the same color on all the injectors. The injector control wire is a different color for each injector.
It also states you should have 11.3 - 15.7 ohms resistance at 68 degrees F.
Dan

 

Ya thats what my haynes manual said, it says check for voltage at the injectors, but I am trying to figure out if 9v is a normal reading on the hot side, I am getting 12v ground on all the injectors.

Wait is the green/red wire the one that is the same on all the injectors the ground wire,

 

The schematic shows dark green/black on all the injectors. They go to a splice. Page 12-43 in the Haynes manual, fig. 6 of 6, fuel inj. wiring, '98 and earlier.
If you have a green/red wire, (instead of dkg/b) on all injectors that is the voltage supply wire.
Dan

 

okay i need to re check that, I have the green/red going to all of them, I need to see if I am getting 9 or 12 on those wire at crank,

 

Okay. Post back with results. I'm not much on electrical, but there are several here who are. Specially Willys55. He's the go-to guy on ZJ electrical problems. He's not on everyday though, but I'm sure he'll find this thread if you haven't figured it out by then.
Dan

 

Today I replaced the Crank position sensor, Still no start, I checked the fuel pump/asd/and all other relays, they are all good, does anyone know what kind of compression on a guage I should be getting while cranking the engine, and also is there anyway to check the ecu, Also I can hear my fuel pump priming for a few seconds when I turn the key, Also I rented a scan tool, No faults were found.