Jeep starts but stop soon as u relaese the key

lock vehicle with either remote or use lock button on door inside car...then goto passenger side door and unlock it with key..this should reset it

i just a 87 jeep mine was doing the same as soon as the key hit the on position, it sometimes starts i replaced the ing module. this took care of mine

I don't quite understand what you mean by be held on. Normally you "hold on" to the key to start it and let it go back to the on position. If you have to hold the key on (start position) then you can might not be starting. The starter is turning the engine, but the engine not running? What happens when you give it gas?

Try locking and unlocking the drivers door using the key. Usually that will re-set the security system. Also try the rear hatch lock as sometimes that is used instead of driver door.

fuel pump relay . you should hear the fuel pump run for 5 seconds as soon as you turn the key on .after that the cranking sensor takes over when engine it turned over to start

relay?

the fuel pump runs on 2 diffierint circuts. one when the key is engaging the starter motor when you are starting the engine, and the other is to power the fuel pump after you release the key when the engine is running. there is a resistor on the drivers side on top of the inner fender that you can over ride with a jumper wire to check. if it needs to be replace its about $5.00. (its a ceramic thing about 2 inches long and bout 3/4 inches square.

either front flex hose or caliper.slack the bleed screw on caliper,if brake releases then problem is rubber flex hose,if dont relaese it is caliper

I have the same model.you must do this .put key in door turn it left and right 3 times .then when you get in put key in ignition turn it 3 times left and right .now start your nice running jeep.thanks Ed

The problem is either in the mechanism that pushes the rod that activates the ignition switch from the key lock cylinder, or the ignition switch is defective.