90 2.5 wouldn't start, now runs rough - Jeep Wrangler Forum

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Old 11-05-2009, 10:43 PM   #1
Join Date: Nov 2009
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90 2.5 wouldn't start, now runs rough

My Mom's 90 2.5 was having intermittent starting issues. It's had new plugs, wires, cap, rotor and coil all within the last month or so. I just replaced the fuel pump along with the tank, but that didn't solve the problem. I then took the ignition control module to autozone to have it tested, and they said it was fine. I put it back in, and now it idles real rough, has no acceleration and nearly stalls coming to a stop. I however think I solved the starting issues by replacing the crank position sensor.

So, I'm wondering could the guy at autozone somehow messed up the ICM when he tested it, and that's causing it to run bad? I assume it's getting fuel because it ran fine for a couple days with the new pump, but I plan on testing the fuel pressure anyway. Also, what kind of fitting do I need for the fuel pressure test port on the 2.5 TBI?

If anyone has some other ideas I'd greatly appreciate it.

One more thing, the previous owner found this part, and thought it came off the Jeep. It's about 2" long and 1" in diameter. Any ideas what it is?

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Old 11-08-2009, 09:34 PM   #2
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Does that piece have an electrical or vacuum connection on the end of it? I sure looks like an emissions piece to me

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Old 11-08-2009, 09:46 PM   #3
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They are vacuum connections. I actually think I figured out where it's from. It looks like a piece that goes on top of the transfer case. I can't remember what it's for though.
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Old 11-09-2009, 09:46 AM   #4
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it looks like the vacuum fitting for the tcase to operate the CAD. have you done a vacuum test?
'90 YJ, ford 8.8, SOA, lincoln front, aussie rear, 4.88s, swampers.
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Old 11-09-2009, 10:25 AM   #5
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No, vacuum test yet. My main concern for now is figuring out the low fuel pressure problem.
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Old 06-06-2011, 07:35 PM   #6
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extra part

That part does go on transfer case and it is the vacuum control for engageing front axle if its been changed to manual you don't need it, but i would save it just in case.
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Old 06-17-2011, 10:32 AM   #7
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Location: stockbridge, MI
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thats the 4 wheel drive actuator on the top of the transfercase. without this, you will have no four wheel drive because the hubs lock in with vacuum. unless it has a manual actualed cable to lock in the front hubs you wont be going anywhere
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Old 06-17-2011, 11:35 AM   #8
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Have you changed the fuel filter? It's easy and inexpensive. A clogged one will cause you problems.

Hee Hee, you ass in a heap o trouble, Boy! ...Great big Georgia state cop
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Old 06-17-2011, 12:56 PM   #9
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I'd go for the fuel filter, if not a catylitic converter that's coming apart and stopping up the exhaust flow...Driller

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