Is this why my TJ is running rough and very rich?

TJ Starting

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2000 4.0, after a very long conglomeration of situations I've got my TJ back together for the second time but it is just dumping fuel out the exhaust and running pretty poorly. Been trying some diagnostics on it and this seems like the most obvious thing so far.

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I know spec is supposed to be right around 40psi. Anyone think or know if this is enough over to be an issue?
 
Will also add that when you shut the engine off it immediately drops to basically zero psi.
 
Any misfires? Since you have a gauge I’d check the FSM and perform a fuel pressure leak down test. That would at least get you started on wether you have an open injector or bad check valve. After that, if you have the equipment, I’d check the fuel trims
 
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X2 on above-was typing mine when Uncle Salty’s posted. 49 psi +/- is perfect For the TJ. I assume this is taken at the fuel rail with the engine running? the pressure should not drop immediately after turning off the engine—both the regulator and the fuel pump have check valves to prevent fast bleed down. Something else is bleeding down. If you are sure it’s running rich and it’s bleeding down quickly, maybe a fuel injector is stuck open?
TJBUD
 
I don't believe it's misfiring, it's just getting flooded with fuel it seems like. No codes for misfire either. There is a code with for #1 injector circuit but that had only popped up since I was messing around with unplugging injectors. I think what I'll do is pull the fuel rail from the manifold and have a buddy crank it just to get a actual visual of what their doing. And yes that fuel pressure was at the rail.
 
Oh and my fuel pressure regulator was also shot. Easy enough to replace. Whole write up in the resources section... don't need to replace the entire assembly.

My CPS was also shot.

And oil pressure sensor.

But I was also getting random misfire codes.

-Mac
 
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Thanks for all the replys, just had a chance to check back in now. #3 injector was stuck in the open position. That side of my issues is gone now. Still have a very intermittent issue with the engine just sound kinda rough like as if it's a 4cyl or something. Not exactly sure how to describe it. Dove very deep into diagnostics this evening. Spark at all 6 spark pugs. Fuel at all injectors. Every sensor on the throttle body was change out with a known good one from my buddys tj as well as the crank position sensor. Fuel pressure still reads a consistent 48ish. Head is also a brand new from Clearwater as of about a month ago.
 
O2 sensors are one of the things I haven't changed out but I have unplugged all of them in an attempt to see if anything would change, nothing did. Seems I read somewhere that if you unplug the o2 sensors they pretty much go back to "default."
 
Good to hear you’ve sold one problem. How’s she running under load? no power? With that raw fuel being dumped into the cat I’d be concerned it’s damaged. if the power is low, check the cat.
 
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Under load I don't think I'd say it has full power but it's not missing a whole lot either. Again, kinda hard to say for sure since I've just took it on a few test drives. When it is running smoothly everything is perfectly normal but it does loose a little when it's in the rough stage. Not sure how to check the cat except visually and it looked intact when I had the Y pipe off.
 
if you suspect a clogged cat, you can check it by removing an O2S and screwing in a low scaled gauge or you can measure vacuum. There’s plenty of YouTube videos.
 
Good to hear you’ve sold one problem. How’s she running under load? no power? With that raw fuel being dumped into the cat I’d be concerned it’s damaged. if the power is low, check the cat.

I'd also be worried about all that fuel washing the cylinder and affecting valve and ring seal. Compression/leakdown tests would be on order
 
Under load I don't think I'd say it has full power but it's not missing a whole lot either. Again, kinda hard to say for sure since I've just took it on a few test drives. When it is running smoothly everything is perfectly normal but it does loose a little when it's in the rough stage. Not sure how to check the cat except visually and it looked intact when I had the Y pipe off.

You can check the cat with an infrared thermal gun. You measure the temp going into the converter and measure the temp going out...


I'd be curious about those upstream 02 sensors... I noticed I had an issue with mine because it ran smooth cold, but once it got warm it was like the computer was getting bad numbers from the sensor and caused a really strong gas smell and bad fuel economy...