ok so i got a 98 jeep xj the other day and it just made it home. it would have a hard time starting once i turn it off so heres what i got. check asd relay and fuse and test out good have good spark and good fuel pressure (49psi) but no injector pulse. i clean the battery terminals and check all the grounds (body and motor) check votage drop (stays above 10 volts) and still will no turn on.. the only way to get it to turn on is if i spay sum starter fluid in the TB and then i start to get a injector pulse.

 

oh and yes i change out the crank sensor even tho it has spark just to be sure

 

May sound crazy. Do you have an Aftermarket alarm?

 

The part that controls the injector pulse is the pickup in the dizzy. That tells the ecu when to fire them. What you also need to check is for any wires resting against the exhaust. Common issue. Check for a relay called asd. Also known as the auto shut down relay. If bad it won't start.

 

no aftermarket alarm but i did check it with a scanner to see if theft or anything and it all check out good saying (fuel on).. yes i also check the hall effect in the dist and thats good too also check the asd relay with the scanner and mutimeter i have power back at the c12 pin and doesnt drop under 10.3 volts while cranking and i have good ground at c3 pin to activate the asd relay and i change the relay for good measure. could my pcm be bad ? it fires up when i spray starter fluid and stays running after with a good injector pulse. it leaves me to belive either a bad pcm or a bad starter not cranking it fast enough (rpm during cranking is 130-146rpm)

 

Try jumping it or giving it a boost.

 

Does fuel pump prime when key is just turned to run posituon for a few seconds?

 

Clean all of your grounds.
Head
Block
Dipstick bolt
PCM

Inspect and replace all ground wires as needed.

 

Camshaft position sensor/circuit, maybe?

 

Manual or auto???

 

It still sounds to me like you have a fuel delivery issue if it pops with starter fluid. The fact that it starts with starting fluid verifies that the engine management system that controls spark, etc. is most likely working properly.

Did you verify that you have 49 psi at the rail with a fuel pressure gauge? In unusual situations, you can have the correct fuel "pressure", but not correct "volume" of fuel. The factory service manual outlines testing for that.

 

Does it stay running after it's started with starting fluid?

 

thanks alot guys for the input!! ok so to answer sum questions. it is a manual trans. ive clean all the grounds the fuel pump does prime up. and yes it stays running after i spary a little bit of starter fluid then the injector pulse comes alive and i can drive it around with no problem no hesitation and good power. as for checking volume havent check that but it runs good after i spray starter fluid and stays running with out it once its on. and i check crank circuit ground and it check out good and i have good spark so i think the crank and cam sensor are out of the question.

 

So again. Have you tried jumping it? If it starts with a jump your batt is weak.

 

yes i used a charger while trying to start it. also switch battery to a 800 cranking amps (calls for a 500ca) and still same thing.