Bwallace33908

Ok so I think I narrowed down my no start issue to the cps but when I pressed the valve on the fuel rail no fuel sprayed out. Could a faulty cps cause low/no fuel pressure or cause the fuel pump to not work??? Any help is appreciated its a dd and its stuck at work...

1988cherokee

what year is your jeep? Can you hear the fuel pump run?

Bwallace33908

Sorry


94 cherokee auto 4x4

I could last night but now I can't?? Don't know why

1988cherokee

to answer your question no a cps wont affect your pump delivering fuel to the fuel rail. You need to check to see if you have power at the fuel pump if you dont then you need to check the fuel pump relay and if I remember correctly the 94 should have an auto shutdown relay too you need to check that if you have power at the pump then I would suspect a bad pump hope this helps

Bwallace33908

Ok so I can hear the pump working.....somehow I was able to drive it home then I turned it off and on a few times and it started right up. Now it won't start again..ughhh

1988cherokee

if it wont start now check to see if you have spark if you dont have spark then I would check the crank sensor chrysler crank sensors have a tendacy to not want to work when hot sometimes or you could have a loose connection somewhere too

Bwallace33908

I bought the cps today the only one in stock was at autozone but it'll work for now. I just don't want to spend all that time putting it on if its not the problem...I will be changing the fuel filter tomorrow also

1988cherokee

be carefull with the autozone crank sensor I bought one from them and the bolt holes werent drilled right so when I put it on it started but it wouldnt rev and it had a real bad miss I had to slot the bolt holes to get the air gap correct

Bwallace33908

Hmmm is there a way to figure out before I try it and have to return it?

1988cherokee

im not sure when I did mine it looked the same but it was off. I would check to see if you have spark the crank sensor tells the computer that the engine is turning and to tell the coil to send spark to the dizzy so check that first.

1988cherokee

if you can scan the comuter for codes it should give a code if the crank sensor is bad or some other problem too

But here is something for you hope it helps

1988cherokee

if you need more diagnostic flow charts just let me know

Bwallace33908

Please excuse if this is a dumb question but to test for spark just pull the wire and hold it close to a metal surface correct?


Thanks for the help too man I appreciate it

1988cherokee

yup just lay it next to metal it helps if you have a helping hand

Bwallace33908

Ok thanks and if there's no spark then it'd be a problem with the distributor right? Assuming all the fuses are good. What if they all have a spark where else should I look?