1990 Renix 4.0 Floods/Backfires
#18
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Year: 1990
Model: Cherokee
Engine: 4.0
#20
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
How's the line from the throttle body to the MAP?
If it is clogged, melted, cracked, loose etc, the MAP gets the idea you're at full throttle and tells the eCU to signal the injectors for a long pulse width.
If it is clogged, melted, cracked, loose etc, the MAP gets the idea you're at full throttle and tells the eCU to signal the injectors for a long pulse width.
#21
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Year: 1990
Model: Cherokee
Engine: 4.0
I gave it a look, looks visually ok.. not sure how to get the one end out of the throttle body, afraid of breaking it.. I did clean the throttle body with spray cleaner, guess I could have clogged it maybe..?
#22
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Year: 1990
Model: Cherokee (XJ)
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With the engine running, unplug it from the MAP. Any change?
#23
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Year: 1990
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I cant get it to start from cold so I cant test. Seems like too much fuel to let it catch. Sputters occasionally and that its. Verified spark and seems to be getting too much fuel, plugs are wet and fuel spraying out the removed plug hole when cranked to verify spark. Is there a way to remove the vac line to the map?
#24
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Unplug it. Can you blow through it? Visually inspect it also.
#25
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I took it off an can blow through it and cleaned out the hole in the throttle body with some cleaner. I took all the plugs out and blew them out with compressed air and go the tons of extra fuel out and then it started. Noticed the oil pressure was low so shut down pretty quick. Checked the dipstick and the it was way over full and smells of fuel, so the fuel has leaked down to the crankcase and I need to change the oil before I can continue.
#26
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Year: 1990
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I took it off an can blow through it and cleaned out the hole in the throttle body with some cleaner. I took all the plugs out and blew them out with compressed air and go the tons of extra fuel out and then it started. Noticed the oil pressure was low so shut down pretty quick. Checked the dipstick and the it was way over full and smells of fuel, so the fuel has leaked down to the crankcase and I need to change the oil before I can continue.
#27
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Year: 1990
Model: Cherokee
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I change the oil and cleaned the plugs last night. Started fine. Shut it off and restarted several times cold and warm. Started this morning before work fine when it was about freezing. Came home after work it started and ran rough and died. Wouldnt restart. Pulled on plug was soaked with fuel. Pull the fuel pump relay and connector on start relay for fuel pump, and cranked it. It started and died when it ran out of fuel. Reconnected relays and it wouldnt start again. Flooding I presume. Was a buzzing sound in the fuel rail/injectors. Disconnected the relays again cranked it and it caught and died when it ran out of fuel. Have no idea what the problem is, totally baffled was great for last night and this morning now its back to acting up. Any ideas?
#28
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Year: 1990
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Pull the vacuum hose off the fuel pressure regulator on the front of the fuel rail. Make sure there's no gas in there.
#29
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Year: 1990
Model: Cherokee
Engine: 4.0
Contact Programbo here on CF for injectors. He knows which ones to get and he has them. Don't get used ones from the junkyard.
www.precisionautoinjectors.com can help you also.
www.precisionautoinjectors.com can help you also.
#30
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Year: 1990
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