4.0 wont start. Need help!!!

Possibility, so I'm gonna throw the upper arms back in it and try to drive it and see if putting a load on the motor tries to bog it out. Then i'd be lead to believe fuel could be my issue (filter or pump)
 
Nothing got done this weekend but im gonna try and mess with it more tonight. I'm at wits end with this thing!! I am completely clueless to what it could be. I'm probably going to change the fuel filter tonight and keep looking for bare wires or something.

Any way timing could be involved?
 
GreyZJ93 said:
Nothing got done this weekend but im gonna try and mess with it more tonight. I'm at wits end with this thing!! I am completely clueless to what it could be. I'm probably going to change the fuel filter tonight and keep looking for bare wires or something.

Any way timing could be involved?
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doubt timing would be involved if it ran good when it did run
 
GreyZJ93 said:
Nothing got done this weekend but im gonna try and mess with it more tonight. I'm at wits end with this thing!! I am completely clueless to what it could be. I'm probably going to change the fuel filter tonight and keep looking for bare wires or something.

Any way timing could be involved?
Click to expand...

When you going to be messing with it? I may come by to shoot the **** and bring your table back that i stole :flipoff2:
 
yeah thats what i was thinking, but i am so confused to why the hell its doing this, that i'm willing to try anything.

steve, ill be out there after work (5:45ish)
 
Have you welded to the Jeep recently with the battery cable on? I can't recall you doing anything off the top of my head. Read something on Pirate about a guy with an XJ on 40s had the same problem and he swapped his ECU and fixed it.
 
Surprisingly enough, i did all the suspension under my jeep with the battery connected. I know your not suppose to but its been kicking for the past 4 years with no problems. But no i didn't do any recently. If i could find a computer i'd swap them to check and see if it fixes it but i dont know anyone with an early zj.
 
Have you tried making up a new ground strap from engine to firewall? Maybe yours got gone when the jack leaked down...it would only take a few minutes to make sure you have proper ground...evev use jumper cables from engine to body and see if it runs then
 
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Found out how to check my codes without a scanner....throwing code 12 and 23
12-is basically saying the computer has no memory in the last 100 key strokes (expected since i did undo the battery cables to attempt to reset the computer)

23- "Air Charge or Throttle Body temperature voltage HIGH/LOW-charge air temperature sensor input is above or below the acceptable voltage limits."

I did take out the MAT sensor when i put the intake manifold into the parts washer to clean it (im pretty sure thats what the sensor is that screws into the intake manifold). Maybe something got damaged while it was sitting on the table? or some people were saying the IAC can be the culprit which i quite possible could have f"ed up when i took it out to clean it.

Could it still not start even if i "fixed" the problem because the computer hasn't been properly reset since fixing it?
 
GreyZJ93 said:
Found out how to check my codes without a scanner....throwing code 12 and 23
12-is basically saying the computer has no memory in the last 100 key strokes (expected since i did undo the battery cables to attempt to reset the computer)

23- "Air Charge or Throttle Body temperature voltage HIGH/LOW-charge air temperature sensor input is above or below the acceptable voltage limits."

I did take out the MAT sensor when i put the intake manifold into the parts washer to clean it (im pretty sure thats what the sensor is that screws into the intake manifold). Maybe something got damaged while it was sitting on the table? or some people were saying the IAC can be the culprit which i quite possible could have f"ed up when i took it out to clean it.

Could it still not start even if i "fixed" the problem because the computer hasn't been properly reset since fixing it?
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if you disconnect the battery for 10 minutes the computer is reset.
 
After it resets, load Windows 95 on it. You'll be good to go ..... 10 miles at a time ...... before a crash.
 
A fast relearn requires more than a 10min battery disconnect.

Remove neg. cable, remove pos. cable, zip tie cables together. Make sure they are contacting. Then press the brake pedal 45-50 times. That should discharge all the PCM capacitor. Then drive a little agressive.
 
She lives!!!!!!!!!!!!!!!! Knock on wood.....I put the upper arms in it and went to start it and it fired right over. Drove it around the neighborhood, came back and shut it off, and then started it back up. No problems. Drove it to work today with no problems either. Keeping my fingers crossed that its finally fixed!!

Not 100% sure if the problems is gone but i wanna thank everyone for their input and advice. Glad i can finally drive it again.
 
GreyZJ93 said:
She lives!!!!!!!!!!!!!!!! Knock on wood.....I put the upper arms in it and went to start it and it fired right over. Drove it around the neighborhood, came back and shut it off, and then started it back up. No problems. Drove it to work today with no problems either. Keeping my fingers crossed that its finally fixed!!

Not 100% sure if the problems is gone but i wanna thank everyone for their input and advice. Glad i can finally drive it again.
Click to expand...

told you putting the arms in would fix it :flipoff2:
 
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