help motor wont crank up in 1988 cherokee pioneer
09-12-2009, 01:54 AM
#1
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help motor wont crank up in 1988 cherokee pioneer
i have a 1988 jeep cherokee pioneer 4.0 the original motor started knocking and smoking so i took it out and put another 4.0 in it the old motor would still crank and run just knocked and smoked real bad but anyways i can turn the motor over and over and over it acts like it wants to crank but dosent it has spark has fire the timing is good the crank shaft position sensor worked in the old motor fine and i put the newer one back in the way i took the old one pleae help me
09-12-2009, 07:16 AM
#2
Capitalization and punctuation woul really help make your post a lot easier to understand.
Need more info.
What year is the donor engine?
Which components were swapped, which were retained?
Need more info.
What year is the donor engine?
Which components were swapped, which were retained?
09-12-2009, 07:57 AM
#4
How do you know you have spark, did you actually pull the plugs and check?
Checked for proper fuel pressure at the rail?
09-12-2009, 08:12 AM
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yes i pulled the plugs out the all have spark and im pretty sure i have all the electrical pluged up right. I went back over everything last night but i can do it again it wouldnt hurt anything
09-12-2009, 11:53 AM
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Year: 1991
Model: Cherokee
Engine: 4.0
you have a 98 you swapped in a 90 motor
now you need the TPS CPS and sensor in the distributor for the98 so the ECU will recognize the signals from then
the sensors from the 90 are not compatible with the 98 ECU
now you need the TPS CPS and sensor in the distributor for the98 so the ECU will recognize the signals from then
the sensors from the 90 are not compatible with the 98 ECU
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09-12-2009, 11:59 AM
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i swaped 1990 motor into a 1988 both 4.0 and i know the motor ran in the jeep i pulled it out of. the only thing is he left it in a mud hole over night and came back the next day and it wouldnt crank so everybody told him that the crank position sensor was bad from all the mud hitting it. wich was cause by him trying to get out of the mud hole
09-12-2009, 12:24 PM
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Year: 1991
Model: Cherokee
Engine: 4.0
i swaped 1990 motor into a 1988 both 4.0 and i know the motor ran in the jeep i pulled it out of. the only thing is he left it in a mud hole over night and came back the next day and it wouldnt crank so everybody told him that the crank position sensor was bad from all the mud hitting it. wich was cause by him trying to get out of the mud hole
with your 98 system
09-12-2009, 02:07 PM
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the motor has fire to all the plugs. i checked the timing it is in time. it is getting fuel. if i unplug the crank sensor it just turns over. if i plug the crank sensor back up it trys to crank so i dont think it is that. what do you guys think it could be
09-12-2009, 02:13 PM
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Year: 1999
Model: Cherokee
Engine: 4.0
definitely worth calling the dealership and seeing if the cps is the same for those two years. I think another important question that was raised was whether you have fuel pressure.
