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suddenly it doesn't work well anymore!

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Old Aug 13, 2022 | 08:00 AM
  #31  
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At least while cranking over.
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Old Aug 13, 2022 | 08:06 AM
  #32  
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Originally Posted by cruiser54
At least while cranking over.
I tried with the car off, I had only turned the key
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Old Aug 13, 2022 | 08:13 AM
  #33  
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Turn the key to Start while testing.
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Old Aug 13, 2022 | 08:22 AM
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Originally Posted by cruiser54
I'm awake now!! 1.5 mugs of coffee ingested...

Here's what Roler uses down in Australia
Morning!
A shot in my morning coffee works wonders too
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Old Aug 13, 2022 | 08:31 AM
  #35  
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Originally Posted by cruiser54
Turn the key to Start while testing.
right, but the engine was off
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Old Aug 13, 2022 | 08:34 AM
  #36  
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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)
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Old Aug 13, 2022 | 08:53 AM
  #37  
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what's the fuel pressure while running?
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Old Aug 14, 2022 | 02:08 AM
  #38  
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Originally Posted by cruiser54
what's the fuel pressure while running?
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????
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Old Aug 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.
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Old Aug 14, 2022 | 10:00 AM
  #40  
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Originally Posted by cruiser54
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.
Fine!
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Old Aug 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.
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Old Aug 15, 2022 | 12:03 PM
  #42  
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Originally Posted by cruiser54
Just for fun, unplug the CPS connector, spray it out with contact cleaner, inspect the pins, and plug it back in.
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).
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Old Aug 15, 2022 | 03:25 PM
  #43  
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Geez, your Jeep is more finicky than my Italian cars!!
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Old Aug 15, 2022 | 04:50 PM
  #44  
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Originally Posted by cruiser54
Geez, your Jeep is more finicky than my Italian cars!!
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
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Old Aug 16, 2022 | 11:28 PM
  #45  
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will the mystery remain unsolved? I do not know what to think....
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