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Fuel injector question

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Old 04-03-2015, 08:12 PM
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Originally Posted by Lanthanaas
Is that the one back by the 2 injectors closest to the windshield? I noticed that set of tubes kept coming apart and looked about as old and corrupted as Satan...
This
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Old 04-04-2015, 12:44 PM
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Alright so if I'm understanding correctly, the hose circled in green is the MAP sensor hose? And it should be attached to the plug circled in yellow? It had fallen down behind the large hose so I didn't realize it wasn't plugged in. I had the red-circled hose plugged into it instead. I'm not seeing anywhere else to plug the odd-hose-out into. Any direction as to which goes where?
Old 04-04-2015, 12:54 PM
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Originally Posted by Lanthanaas

Alright so if I'm understanding correctly, the hose circled in green is the MAP sensor hose? And it should be attached to the plug circled in yellow? It had fallen down behind the large hose so I didn't realize it wasn't plugged in. I had the red-circled hose plugged into it instead. I'm not seeing anywhere else to plug the odd-hose-out into. Any direction as to which goes where?
Someone has messed with your stuff.

Perhaps this will help:
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Old 04-04-2015, 01:20 PM
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Originally Posted by cruiser54
Someone has messed with your stuff.
Yeah the guy who originally had the Jeep knew what he was doing and made a bunch of great modifications. Unfortunately, there were 2 owners between him and me who screwed up a lot. I'm in contact with the original owner and he and I are undoing the messes they made little by little.
Old 04-04-2015, 01:59 PM
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Originally Posted by Lanthanaas
Yeah the guy who originally had the Jeep knew what he was doing and made a bunch of great modifications. Unfortunately, there were 2 owners between him and me who screwed up a lot. I'm in contact with the original owner and he and I are undoing the messes they made little by little.
Well, the diagram should help. No issue using another source of vacuum for the MAP as long as the throttle body vacuum source is properly plugged.
Old 04-04-2015, 02:49 PM
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Originally Posted by Lanthanaas
the hose circled in green is the MAP sensor hose? And it should be attached to the plug circled in yellow?
Yes, it will work with any manifold vacuum source. Like mentioned, make sure where it originally belonged is plugged.
Old 04-04-2015, 03:18 PM
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Originally Posted by DFlintstone
Yes, it will work with any manifold vacuum source. Like mentioned, make sure where it originally belonged is plugged.
Correct.
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Old 04-05-2015, 08:22 PM
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Alright, so the red circled hose connects to a small metal line. It runs down through the engine compartment, back along the undercarriage with a few others, and then plugs into a rubber line that disappears over the gas can. Any ideas what it is and where it should be plugged in? I have some pictures of the path if they will help.
Old 04-05-2015, 09:41 PM
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I wondered about that circled in red. The IAT, incoming air temp, goes there I think, just has two wires. The other bit reminds me of an Escher print.
Old 04-05-2015, 09:48 PM
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Originally Posted by Lanthanaas
It runs down through the engine compartment, back along the undercarriage with a few others, and then plugs into a rubber line that disappears over the gas can. Any ideas what it is and where it should be plugged in?
Yea, more pics. The vent from the tank goes to the evap canister. It just is "vented" to the incoming air, not manifold vacuum.

Did hooking up the MAP line make it run OK?
Old 04-06-2015, 10:54 PM
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Under the engine where the metal line comes down from the red hose. It's the one on the top.


Last edited by Lanthanaas; 04-06-2015 at 10:57 PM.
Old 04-06-2015, 11:03 PM
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Attached Thumbnails Fuel injector question-2-backfromengine.jpg   Fuel injector question-3-bwsidereardswheel.jpeg   Fuel injector question-4-acrossrearundercarriage.jpeg   Fuel injector question-5-upovergastank.jpeg  
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Old 04-09-2015, 08:27 PM
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Alright, with the sensor hose plugged in, I'm still having the symptoms. Running rough, idling lower and lower until it's almost sputtering out.
Old 04-09-2015, 09:22 PM
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Originally Posted by Lanthanaas
Alright, with the sensor hose plugged in, I'm still having the symptoms. Running rough, idling lower and lower until it's almost sputtering out.
Was it not plugged in previously?
Old 04-09-2015, 10:25 PM
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Originally Posted by Lanthanaas
Running rough, idling lower and lower until it's almost sputtering out.
Does it "catch it's breath", speed up for a second, then repeat, or just keep spuddering? An O2 sensor can do that, make the idle cycle. Have you looked at Cruiser's tips? The sensor ground check is amongst some great info.

Cleaning the IAC and adjusting the TPS is supper stuff also. They both are important for idle. Myself, the IAC plug it's self was stubborn to clean.

Oh, just saw Cruiser's last post. Maybe if it had been run much with the map line off, it's all carboned up.

Last edited by DFlintstone; 04-09-2015 at 10:31 PM.


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