I just bought a 90 xj 2door sport 4.0 and i have replaced the battery, fuel sending unit and plugs. it turns over just fine and it has compression. it isnt getting fire to the coil or signal to the injectors. is there anybody that can tell me what might be wrong?

 

crank position sensor maybe?

 

i looked for one but cant find one. does it even have it?

 

driver side of the bell housing, It is bolted with two 7/16 inch bolts and has a cable that runs up to the engine compartment.

 

thanks. ill find out if thats good first. pcm here i come.

 

For sure its the cps same thing happened to mine not long ago

 

I replaced the cps and I got it to start. It ran about 3 seconds and cut off. Hasn't started since

 

injector pulse is controled by the cam position sensor /hall effect sensor

 

un plug it and plug it back in see what happens

 

sensor tsting info herehttp://www.lunghd.com/Tech_Articles/...iagnostics.htm

 

okay so i tried the unplug and plug thing and that didnt work. i am getting fire now and i have fuel pressure on the rail. but it still wont start. its really starting to frustrate me. what else could be wrong

 

have you looked at/checked the throttle postition sensor? or the air intake control? is the throttle body dirty/need cleaning? i just changed my map sensor after a multitude of diagnosing various electrics and that got mine running like a champ. how much fuel pressure are you getting on the rail? another thing i've noticed is that if the computer isn't getting enough voltage it won't run properly as well...good luck!

 

what about injector pulse ,you can have all the fuel pressure you need but if theres no injector pulse it wont start try squirting starting fluid in the throttle body see what happens

 

Okay guys I've been working alot lately so i havent had too much time to work on the jeep but i got the last few days off and i been trying to get it right. i have now replaced the computer and put a new battery in and it acts like it wants to fire up but it doesnt. any ideas?

 

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