89 Cherokee 4.0

Mike88se

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Okay... 3 cans of carb cleaner not seafoam :ashamed: If it's intake, you won't need carb cleaner and I don't think it's a small vac leak. I think it would need to be a big leak to cause all that. The 4.0 is a good engine and pretty easy to work on. Lots of room under the hood. My ZJ had a self diagnostics you could run using the ignition key. Not sure if the XJs had that. But then my ZJ had a problem that didn't show in the test and took me weeks to figure out the ecu had 2 fried capacitors ;) Bought new ones from Radio Shack and soldered them in and never had another problem.
Have fun ;)
Ya I did the computer relearning ill look at the egr tom if it is vac or intake I can't find it like I said I emptied 3 cans of carb cleaner looking
 

exotion

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Okay... 3 cans of carb cleaner not seafoam :ashamed: If it's intake, you won't need carb cleaner and I don't think it's a small vac leak. I think it would need to be a big leak to cause all that. The 4.0 is a good engine and pretty easy to work on. Lots of room under the hood. My ZJ had a self diagnostics you could run using the ignition key. Not sure if the XJs had that. But then my ZJ had a problem that didn't show in the test and took me weeks to figure out the ecu had 2 fried capacitors ;) Bought new ones from Radio Shack and soldered them in and never had another problem.
Have fun ;)

I have thought about and haven't pulled the ecu.. if my alt has been going out for a long time like I said the bearing whined for about a year about 7500 miles I am wondering if it put out less power while it was whining then when I put a new one on the different amperage could have friend something in the ecu

Also when it went out the bearing seized and pulley with it my wife continued to drive it squealing like a mofo for a couple mins if that extra strain on the belt threw off something. I couldn't even turn the pulley at all when I got the old alt off.

Another thought is that the transmission clunks when in drive and stopped at a stop light I think that's the torque converter but possibly flywheel and if it is flywheel could that throw my engine power for a loop
 

Mike88se

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I think your ecu is probably fine. There was a little problem with Jeep XJ and ZJ ecu's but not widespread. I don't think driving it after the bearing seized would do anything except kill the belt.
Pretty sure nothing in the transmission would cause this.
I'm still thinking its something simple... maybe not easy to find but simple ;) A plugged up cat could cause something like that too. I know you checked it a while back but if you don't have emissions testing ... :thumbsup:
In TX any vehicle over 25 years old doesn't need to pass emissions. Legally we'd still be required to have a cat and a punched out cat can be noisy.
I have thought about and haven't pulled the ecu.. if my alt has been going out for a long time like I said the bearing whined for about a year about 7500 miles I am wondering if it put out less power while it was whining then when I put a new one on the different amperage could have friend something in the ecu

Also when it went out the bearing seized and pulley with it my wife continued to drive it squealing like a mofo for a couple mins if that extra strain on the belt threw off something. I couldn't even turn the pulley at all when I got the old alt off.

Another thought is that the transmission clunks when in drive and stopped at a stop light I think that's the torque converter but possibly flywheel and if it is flywheel could that throw my engine power for a loop
 

exotion

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I think your ecu is probably fine. There was a little problem with Jeep XJ and ZJ ecu's but not widespread. I don't think driving it after the bearing seized would do anything except kill the belt.
Pretty sure nothing in the transmission would cause this.
I'm still thinking its something simple... maybe not easy to find but simple ;) A plugged up cat could cause something like that too. I know you checked it a while back but if you don't have emissions testing ... :thumbsup:
In TX any vehicle over 25 years old doesn't need to pass emissions. Legally we'd still be required to have a cat and a punched out cat can be noisy.

No the cat was my original diagnoses I took it to a muffler shop to test they pressure tested it said its good but my muffler has a hole that needs fixed tho lol it has to be something simple but I have looked and looked. I did notice that one of my injectors is kinda touchy if you put any pressure on it it leeks gas but doesn't if you don't touch it. So another thing on my list are mustang 5.0 injectors but again not investing untill its running
 

Mike88se

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Process of elimination ;) I'd skip the Ford injectors unless they have the same flow rate and are a direct fit. And unless you can reprogram the ecu and fab new fuel rail and get more air in the intake. Gotta keep that a/f ratio right.
No the cat was my original diagnoses I took it to a muffler shop to test they pressure tested it said its good but my muffler has a hole that needs fixed tho lol it has to be something simple but I have looked and looked. I did notice that one of my injectors is kinda touchy if you put any pressure on it it leeks gas but doesn't if you don't touch it. So another thing on my list are mustang 5.0 injectors but again not investing untill its running
 
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Ya been over all the electrical nothings seems unplugged, I probably emptied 3 cans of carb cleaner looking for vac leaks



But was it running good when you changed the alternator?
 

exotion

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I hate see that repair bill. Probably gonna be a $500 or more bill.

Well the guys shop is litterly a block away and I do landscape work for him and last time I needed help I bartered labor work so I only paid for the part
 
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Well the guys shop is litterly a block away and I do landscape work for him and last time I needed help I bartered labor work so I only paid for the part




Let us know what he figures out.
 
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