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Help!! Fuel injector swap gone wrong!! 2000 4.0

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Old 03-04-2011, 10:32 PM
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Thumbs down Help!! Fuel injector swap gone wrong!! 2000 4.0

So I spent the afternoon swapping out my fuel injectors on my 2000 4.0L XJ. I bought a set of six rebuilt Ford #19's from one of the guy's on ebay that has all the fancy equipment to test and match and what not. I've spent hours reading the forums and thought I was ready for the big show.

Everything went pretty smooth. I reset the ECM according to the instructions on here (I think it reset anyway...) and went to start the Jeep and everything sounded great. Then I started smelling gas, a lot of gas. None of the injectors were leaking and I realized that it was from the exhaust. I literally have gas dripping out my tail pipe!!

Very discouraged and I'm hoping someone could point me in the right direction as to what could cause this. Everything was running ok before the swap. What did I do wrong? Thanks for your help!
Old 03-04-2011, 11:39 PM
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Originally Posted by Chumster
So I spent the afternoon swapping out my fuel injectors on my 2000 4.0L XJ. I bought a set of six rebuilt Ford #19's from one of the guy's on ebay that has all the fancy equipment to test and match and what not. I've spent hours reading the forums and thought I was ready for the big show.

Everything went pretty smooth. I reset the ECM according to the instructions on here (I think it reset anyway...) and went to start the Jeep and everything sounded great. Then I started smelling gas, a lot of gas. None of the injectors were leaking and I realized that it was from the exhaust. I literally have gas dripping out my tail pipe!!

Very discouraged and I'm hoping someone could point me in the right direction as to what could cause this. Everything was running ok before the swap. What did I do wrong? Thanks for your help!

Sounds like you have one or more injectors stuck in the open position, flooding you with gas.
Old 03-05-2011, 12:05 AM
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Originally Posted by desertw0lf
Sounds like you have one or more injectors stuck in the open position, flooding you with gas.
Thank you for your quick response! That would make sense. There is a ton of fuel coming out the tail pipe! Do you know of a way to test and see which one it could be?
Old 03-05-2011, 12:11 AM
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Are you sure it's gasoline not condensation !! Having just installed new injectors and resetting the computer the system will run default until it relearns.
Old 03-05-2011, 12:32 AM
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Originally Posted by radio flyer
Are you sure it's gasoline not condensation !! Having just installed new injectors and resetting the computer the system will run default until it relearns.
I'm pretty confident it's gasoline. You can smell gas SUPER strong when I fire it up and smelling the exhaust fumes it's obvious it is running crazy rich. And the engine starts struggling like it's getting flooded and about to die.

You bring up a good point though. I know the mist is strong in gas but the liquid dripping from the tail pipe could be condensation. I just assumed it was gas from the smell of the fumes but I'll check it out in the morning to see if it's just water dripping.

Thanks for ya'lls input and if anyone else has any other suggestions Please pipe in! This is my wife and mine's only vehicle so it's pretty crucial we figure out what's going on, like soon!!! I emailed they guy I bought them from so hopefully he'll have something!
Old 03-05-2011, 04:35 AM
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try tapping each injector lightly to unstick it
Old 03-05-2011, 03:19 PM
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Well i took all the injectors out and cleaned them real good again and put everything back together and was having the same issue. Tons of gas coming out the exhaust.

I called the dealership to see if I would be okay to drive it and they said yes (BTW the tech seemed appalled that I touched the two terminals together to reset the PCM. He said all you have to do is take the negative battery terminal off for at least 15 minutes and that should due.)

So I went a drove around a little bit and within the first warm up cycle the Jeep figured out it was sending too much gas through. It's running awesome now. The getupandgo was insane! Maybe my old injectors were just really dirty but these injectors increased the power significantly!!
Old 03-05-2011, 03:28 PM
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Happy endings are awesome. I want to do the same thing but the wife heard me talking about it and doesn't want me to "mess with a good thing".
Old 03-05-2011, 03:35 PM
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whats ur mpg like now since the swap?
Old 03-05-2011, 03:48 PM
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One thing you might want to do is pull the dipstick & give it the sniff test to make sure your oil isn't diluted with gas. It's amazing how fast you can get gas down in the crankcase when they're running rich. If you have gas in the oil it can ruin a lower end pretty quick & an oil change is cheap insurance.

Jim
Old 03-05-2011, 07:55 PM
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Just a tip...... if you want to check and see if some liquid is gas or has any in it all you have to do is take a coffee cup and catch a bit of the liquid.
Gas will go right thru a styro foam cup melting it almost instantly.
Old 03-05-2011, 10:58 PM
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I saw a video some where on how to clean and test the injectors. They used a syringe and carb cleaner to do this. I can't remember where, it had to be in this forum somewhere. If anybody knows this, please post so I can make better notes.
Old 03-05-2011, 11:14 PM
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Originally Posted by xjmuddigger
whats ur mpg like now since the swap?
I would also like to know this
Old 03-05-2011, 11:59 PM
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I put new ford injectors in mine. I went from 230 a tank to 245 ish... so about 1mpg. but the idle and throttle responce was where the big notice in change was.
Old 03-06-2011, 12:20 AM
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Originally Posted by Gorillaxj
I put new ford injectors in mine. I went from 230 a tank to 245 ish... so about 1mpg. but the idle and throttle responce was where the big notice in change was.
I also went from 225ish a tank to 250ish a tank after the swap. I used the "917" injectors in my 2000.


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