suddenly it doesn't work well anymore!
08-13-2022, 08:00 AM
#31
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
At least while cranking over.
08-13-2022, 08:13 AM
#33
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Turn the key to Start while testing.
08-13-2022, 08:22 AM
#34
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08-13-2022, 08:34 AM
#36
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Year: 1990
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anyway after the test the jeep started up and runs fine .... but I haven't done anything since it didn't even turn on (apart from spending some money for the fuel pressure test kit)
08-13-2022, 08:53 AM
#37
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what's the fuel pressure while running?
08-14-2022, 02:08 AM
#38
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Year: 1990
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with the engine running, accelerating, it moves between 30 and 31.
But a strange thing has happened: the jeep was off since yesterday and did not start (I wanted to move it to the shade for the test), and did not start !!! After I did the test (first with the engine off of course), the jeep started and runs normally .....
Why????
But a strange thing has happened: the jeep was off since yesterday and did not start (I wanted to move it to the shade for the test), and did not start !!! After I did the test (first with the engine off of course), the jeep started and runs normally .....
Why????
08-14-2022, 07:50 AM
#39
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What kind of electrical wires/connections could you have touched or moved to do the test?
Something to try. With the engine running, wiggle the wire harnesses in the engine bay. Especially those around the intake manifold. You have completed tip 2, correct?
30 to 31 running is okay.
Something to try. With the engine running, wiggle the wire harnesses in the engine bay. Especially those around the intake manifold. You have completed tip 2, correct?
30 to 31 running is okay.
08-14-2022, 10:00 AM
#40
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What kind of electrical wires/connections could you have touched or moved to do the test?
no cable or connector touched for the fuel pressure test, I had only unplugged and reattached the MAP sensor connector some days ago .
Something to try. With the engine running, wiggle the wire harnesses in the engine bay. Especially those around the intake manifold. You have completed tip 2, correct?
Correct
30 to 31 running is okay.
no cable or connector touched for the fuel pressure test, I had only unplugged and reattached the MAP sensor connector some days ago .
Something to try. With the engine running, wiggle the wire harnesses in the engine bay. Especially those around the intake manifold. You have completed tip 2, correct?
Correct
30 to 31 running is okay.
08-14-2022, 10:22 AM
#41
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Just for fun, unplug the CPS connector, spray it out with contact cleaner, inspect the pins, and plug it back in.
08-15-2022, 12:03 PM
#42
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Year: 1990
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i checked the cps connector, and it's okay. everything remains inexplicable, if the jeep is off for a few hours it starts with difficulty or even does not start. I do the fuel pressure test and the jeep works. (I also tried to drain a little bit of petrol from where the tester pressure gauge is connected and the jeep started).
08-15-2022, 03:25 PM
#43
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Geez, your Jeep is more finicky than my Italian cars!!
08-15-2022, 04:50 PM
#44
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I'm dating myself but remember the movie"Christine" with the possessed car?
Somehow related. When I used to do this stuff for a living some people with early VW Rabbits would go out in the morning and the car wasn't where they left it. Turned out that if you had a manual transmission, parked it in gear,didn't set the parking brake and it rained water would come in thru a badly sealed antenna wire and run down onto the board that had a starter relay on it. The starter motor would then move the car. Took them a while to figure that one out
Somehow related. When I used to do this stuff for a living some people with early VW Rabbits would go out in the morning and the car wasn't where they left it. Turned out that if you had a manual transmission, parked it in gear,didn't set the parking brake and it rained water would come in thru a badly sealed antenna wire and run down onto the board that had a starter relay on it. The starter motor would then move the car. Took them a while to figure that one out