Engine replacement issue

Morks

Morks

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I have swapped a 2003 engine into my 2004 sport. I have all of my electrical connections hooked up and all the pieces put back together. I am having a couple of issues. One, my voltmeter and fuel gauge aren't reading (bad cps)?. Next, it doesn't even attempt to crank (bad cps lol). 2 things I can think of is the small plastic piece that holds the crank position sensor in place fell out, but I put it back in (maybe a certain way is needed, even though it can only go one way), and my ground (107 I think) to the engine block at the dipstick tube I ended up breaking the tab off to I soldered the one with two wires together.
 
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Sorry for the million posts lol. I found a bad ground, fixed that up, and have my gauges back. The only thing is I am not getting power from the key to the starter, I wired the starter to the battery and it cranks over with no issues. Just one missing link now.
 
So, I load tested the battery and figured out it was pretty bad, have a new one now. Still, nothing to the starter and realized the fuel pump is not pumping fuel. Starting with just the starter first, the relay is getting power, and the fuse inside the glove box is good. So I went to the dash, actuator pin is good. Next looked at the ignition switch and its connections and this is what I have got:

Red - always hot
yellow - never
blue - never
black/green - never
pink/white - never
black/orange - never
pink/red - always
pink/black - always
blue/grey - always
black - never
Assuming all the ones (main color black) are grounds
and as is 0 power to the trigger wire on the starter
 
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Since fuel pump operation is dependent on a functioning crankshaft position sensor I would start there. The oem when new has a paper spacer on the face that is ground off the first time the flywheel rotates setting the proper gap and yours may be off.
 
TJ4Jim said:
Since fuel pump operation is dependent on a functioning crankshaft position sensor I would start there. The oem when new has a paper spacer on the face that is ground off the first time the flywheel rotates setting the proper gap and yours may be off.
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Ah okay, for the plastic holder on the transmission for it I had 2 pieces laying on the ground. Are there supposed to be 2 pieces holding it in (one of them could have come off the old engine crap) or just the one? I also should add the first time trying to fire up the jeep I could get power to the starter and it would want to crank but did not have enough juice with the crappy battery.
 
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Morks said:
Ah okay, for the plastic holder on the transmission for it I had 2 pieces laying on the ground. Are there supposed to be 2 pieces holding it in (one of them could have come off the old engine crap) or just the one? I also should add the first time trying to fire up the jeep I could get power to the starter and it would want to crank but did not have enough juice with the crappy battery.
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Have not come across any 2 piece CPS's, typically just a sensor and a rubber grommet weather seal so you may have damaged the sensor. Replacements should be NTK or Mopar and the Echlin from NAPA work also, all others can be a crap shoot.
 
TJ4Jim said:
Have not come across any 2 piece CPS's, typically just a sensor and a rubber grommet weather seal so you may have damaged the sensor. Replacements should be NTK or Mopar and the Echlin from NAPA work also, all others can be a crap shoot.
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Not the actual cps, the little plastic piece that it sits in that goes in the bell housing. I ordered an ntk from the local parts store said 2 hrs and it'll be there so that is nice. I am trying to figure out which wires mean what going to the ignition switch... Seeing if I can at least jump the starter from there.
 
Morks said:
Not the actual cps, the little plastic piece that it sits in that goes in the bell housing. I ordered an ntk from the local parts store said 2 hrs and it'll be there so that is nice. I am trying to figure out which wires mean what going to the ignition switch... Seeing if I can at least jump the starter from there.
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Post a pic but have never seen a cps that used a plastic piece you describe, unless you talking about the grommet for the opening.

At this point try the new one.
 
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TJ4Jim said:
Post a pic but have never seen a cps that used a plastic piece you describe, unless you talking about the grommet for the opening.

At this point try the new one.
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Yeah, the grommet for the opening! For the ignition pin with the little gold piece and the spring is there a part number for the spring just lost it in the driveway... This thing has been kicking my ass the past couple of days!

image0 (15).jpeg
 
TJ4Jim said:
Unfortunately sold as a unit.
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Headed to practice, and to pick up the cps and I am just gonna grab an ignition switch just in case. Hopefully not too dark by the time I get back, I will let you know how I make out, thanks.

edit: I just thought of this, since having the "new" engine I left its cam position sensor in it, because that wouldn't have run with my crank position sensor could that have messed it up?
 
Morks said:
Headed to practice, and to pick up the cps and I am just gonna grab an ignition switch just in case. Hopefully not too dark by the time I get back, I will let you know how I make out, thanks.

edit: I just thought of this, since having the "new" engine I left its cam position sensor in it, because that wouldn't have run with my crank position sensor could that have messed it up?
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Same sensor either year so it should not be an issue.
 
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TJ4Jim said:
Same sensor either year so it should not be an issue.
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Figured, practice ran late, will try it out tomorrow. Is it worth it to even try and test the cps? My buddy works at the store and somehow the old man on the phone took ntk as bwd and he said just return it if you don't want it after trying lol... I'll plug it in to try but skeptical about the brand haha. Just ordered an actual ntk online so if it is a bad sensor I can keep the bwd as a backup to at least get back from trail.
 
Morks said:
Figured, practice ran late, will try it out tomorrow. Is it worth it to even try and test the cps? My buddy works at the store and somehow the old man on the phone took ntk as bwd and he said just return it if you don't want it after trying lol... I'll plug it in to try but skeptical about the brand haha. Just ordered an actual ntk online so if it is a bad sensor I can keep the bwd as a backup to at least get back from trail.
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Crap shoot either way.
 
TJ4Jim said:
Crap shoot either way.
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Yeah exactly, just read a post from Blaine saying a 97-04 will not even attempt to start with a shot cps, hoping that's the case. I will let you know how I make out.

edit: just put the cps in and ignition switch and nothing.
 
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Just went back to simple, chopped the grounds, and redid them all. The engine fired right up!
 
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Morks said:
Ah okay, for the plastic holder on the transmission for it I had 2 pieces laying on the ground. Are there supposed to be 2 pieces holding it in (one of them could have come off the old engine crap) or just the one? I also should add the first time trying to fire up the jeep I could get power to the starter and it would want to crank but did not have enough juice with the crappy battery.
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I’m running into what appears to be the same issue. Can you change the cps with the engine installed? You don’t have to take it all back out do you?
 
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RAC02 said:
I’m running into what appears to be the same issue. Can you change the cps with the engine installed? You don’t have to take it all back out do you?
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Nope, try diagnosing what the issue is first, but you can change it pretty simply. Plenty of youtube videos.
 
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