Hi my name is Jason im new to the forum. I recently bought a 1994 Jeep cherokee 4.0L automatic 231 transfer case. Has been sitting for 2 years and had hole in bottom of gas tank. To start I remover the tank and took the sending unit out of the tank and placed it in a bucket of gas and hooked it back up. I wanted to make sure the motor ran before I put any money into this rig. I turned the key on and pump kicked on and went off after about 3 sec. Turned key to crank and thats all it did was crank and crank, no start. Checked for spark at all 6 cyl. all were good. Checked for fuel at rail, had pressure at rail. Tried cranking again, still no start. Tried again this time sprayed ether in intake and it took right off and kept on running. Shut off and tried to start again, no start. Acts like the injectors are not working at start up cranking. How can I fix this?

 

Start by checking the fuel pressure with a pressure gauge attached to the fuel rail to make sure you have the right pressure. For a 94 it should have 39psi + or - 5psi. Just pushing the valve on the fuel rail only tells you that it's got fuel but you have to make sure you have the right pressure. Test that out and let use know what you find.

 

Does it start with ether and run still after first time ?

 

It will start on ether every time, and run fine after that till you shut it off. Then you have to use ether again to start it. Ill try to get a fuel pressure at the rail today after work.

 

If its running fine you've got fuel pressure . Does pump still run for a few second when keys first turned to run which indicates priming ?

 

Try switching out auto shut down relay yet....also there a ballast resistor bypass relay by pdc box might check into that if 94 has one.

 

Ok guys just went down and tested the fuel pressure. Cycled key and it went to around 28psi. Then I cranked it and it went to around 44psi but did not start. Took the plug of #1 injector and wile cranking it was 14.2 volts from one post to battery ground. Other post was dead figuare its the ground side. Tested between the two post will cranking- nothing. Put plug back on the injector and drained pressure tester in to intake. Cranked and started right up. fuel pressure wile running was around 34psi. Pulled injector plug back off wile running and put volt meter between the to post and i could watch it go up and down as it cycled. Im at a loss is the ECU messed up?

 

Went and checked for the auto shut down relay and ballast bypass relay my jeep doesn't have either.

 

I have been doing some searching on the internet and have a ?. Should my jeep have a relay in the ASD relay spot? There's a spot labeled for it but no relay in it.