I need help with my cherekee
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I have 1988 jeep cherekee, inline six cyclinder 4.0 L, its a MPI,
(multi point injection). i was having fuel delivery problems. jeep woud shut off when hot or after warming the engine the car wont start i ended up changing the pump and it worked then it started acting funny when I started the car after a couple minutes it started idling eractically and when i would try to step on the gas to bring the rpm up it would either not have any effect or start making a bucking type of sound when the accelerater pedal was pressed i then changed the fuel filter because it seemed as if the fuel wasnt getting delivered it worked for a day or 2 again and then the same thing started happening. I was told by a walk by machanic that my throttle position sensor needed to be change because the fuel air ratio was not correct or something like that so I went and got the TPS and I installed it after I started the car and it sounded kinda smooth I went upstairs because it started raining and when it stop i went downstairs to take it for a test drive and it wouldnt start it was as if it wasnt getting any fuel I believe I have a short in my fuel injector wire connectors somewhere so it may stop fuel from coming I sprayed a little MAF air flow sensor into the air intake arm positioned over the throttle body and when i tried to start the car it started but the idle or rpm was at the 3 mark when its suppose to be a little under the 1 I turned the idle down and it did nothing to the arm of the rpm it stays at the 3 as if it wants to go over not to mention the loud roaring sound as if im pressing the gas and when I put it in drive it drops down to the 2 mark on the rpm but still has that loud whine or roaring noise. please tell me what i need to do to fix my car?
(multi point injection). i was having fuel delivery problems. jeep woud shut off when hot or after warming the engine the car wont start i ended up changing the pump and it worked then it started acting funny when I started the car after a couple minutes it started idling eractically and when i would try to step on the gas to bring the rpm up it would either not have any effect or start making a bucking type of sound when the accelerater pedal was pressed i then changed the fuel filter because it seemed as if the fuel wasnt getting delivered it worked for a day or 2 again and then the same thing started happening. I was told by a walk by machanic that my throttle position sensor needed to be change because the fuel air ratio was not correct or something like that so I went and got the TPS and I installed it after I started the car and it sounded kinda smooth I went upstairs because it started raining and when it stop i went downstairs to take it for a test drive and it wouldnt start it was as if it wasnt getting any fuel I believe I have a short in my fuel injector wire connectors somewhere so it may stop fuel from coming I sprayed a little MAF air flow sensor into the air intake arm positioned over the throttle body and when i tried to start the car it started but the idle or rpm was at the 3 mark when its suppose to be a little under the 1 I turned the idle down and it did nothing to the arm of the rpm it stays at the 3 as if it wants to go over not to mention the loud roaring sound as if im pressing the gas and when I put it in drive it drops down to the 2 mark on the rpm but still has that loud whine or roaring noise. please tell me what i need to do to fix my car?
#2
sounds like you have a stuck throttle, first have you checked for any obstructions keeping the throttle from closeing properly? then you will need to get you engine codes read to see if you have any other problems that need repaired.
murphy was an optimist.
murphy was an optimist.
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88 you say????............Welcome to the "wonderful world of Renix" (Renault/Bendix)...........Sounds like you have a CLASSIC case of weak crank sensor..........There will be a 2 wire plug on the left rear of the engine........wires will be white and red.......follow them down to the top of the trans.........This was VERY common back in the day with jeep XJ's.........If you disconnect the sensor and connect a DVOM to the sensor They want to see about .5 volt A/C current while cranking.........I'll bet when you have "no start" you'll find the voltage is less than .25 volt A/C........
One other thing........Jeeps of that era had several updated ECU's for runability problems.........
One other thing........Jeeps of that era had several updated ECU's for runability problems.........
#4
Sounds like you have a CLASSIC case of weak crank sensor.
Agreed......
Not idiot proof..but to test them easily...a 2 litre soda bottle filled with cold tap water.....next time the truck acts up, pour the bottle down the "BACK" of the engine onto the transmission bellhousing. If the truck starts and runs ok till it heats up again......Replace the Crank sensor.....
Just a note.....I personally have had nothing but bad luck with aftermarket sensors......Go to your local "Chrysler/Jeep" dealer, and spend the few extra bucks for an "OE" sensor....
Welcome to the "wonderful world of Renix"

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what do you mean updated ECU's? so basiclly ur saying buy another crank sensor? I just brought 1 a couple months ago, i thought when crank sensor is faulty car wont crank? Thats why i changed it before
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OK........The crank sensor generates A/C voltage that the ECU interprets as the engine spinning.......If you had the trans out of the vehicle, you'd see on the flywheel a whole bunch of nubs 2 of which would be larger........As the engine spins the CS counts,........ and the see's the 2 bigger ones........90deg to and then TDC........If the ECU doesn't SEE voltage from the CS then as far as it knows, the engine's not turning and there's no need for spark or fuel delivery..........so it doesn't do either.
Renault (who owned jeep in that era) updated their ECU's several times........So you may be looking at a combination of 2 problems
Renault (who owned jeep in that era) updated their ECU's several times........So you may be looking at a combination of 2 problems
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jesus i thought maybe a vacuum was off somewhere or the throttle might be stuck because i got the car to start regularly after i wiggled the fuel injectors wires along the fuel rail then it started but my rpm is at like 3000 (the 3 mark) its sounds as if my foot is on the gas.
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i need help with my cherekee
i found a way to take the idle down when its idling at the 3 i unpluged the TPS the idle drops then i plug both connecters back and the idle goes back to normal. My problem is once the car is warmed up it doesnt start back up no fuel getting to the engine what can i do im still getting spark to the ignition