Renix era issues
02-12-2018, 07:41 AM
#16
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Year: 1999
Model: Cherokee(XJ)
Engine: 4.0
Originally Posted by Oswalla
I would have to agree, it is more common than a rich condition. Wonder how his temps are ? Lean can heat up the motor.
Satirical Hen, hows that exhaust look I mentioned earlier ? Rich condition will generally be excess black smoke when revved. Another rich sign is easy to check those plugs, if they look good and dry follow the lean condition. Get an extension hose for that pressure tester and run it up to windshield and drive it like Cruiser suggested.
Satirical Hen, hows that exhaust look I mentioned earlier ? Rich condition will generally be excess black smoke when revved. Another rich sign is easy to check those plugs, if they look good and dry follow the lean condition. Get an extension hose for that pressure tester and run it up to windshield and drive it like Cruiser suggested.
02-12-2018, 07:43 AM
#17
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Have you checked the tightness of the intake manifold nuts?
sprayed carb cleaner at suspected vacuum leaks with the engine running?
sprayed carb cleaner at suspected vacuum leaks with the engine running?
02-12-2018, 08:12 AM
#18
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Year: 1999
Model: Cherokee(XJ)
Engine: 4.0
Originally Posted by cruiser54
Have you checked the tightness of the intake manifold nuts?
sprayed carb cleaner at suspected vacuum leaks with the engine running?
sprayed carb cleaner at suspected vacuum leaks with the engine running?
02-12-2018, 08:14 AM
#19
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
I haven't gone and tightened the intake bolts, but there doesn't seem to be any vacuum leaks. Idles right at 750 and I haven't been able to locate any leaks. I disconnected the heater valve, but plugged the vacuum line to it. Don't know if it makes a difference, but when I'm on the brakes it idles up and I can hear an air sound and when I let off idle will drop for a second then pick back up.
02-13-2018, 08:38 PM
#21
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Year: 1990
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02-13-2018, 09:35 PM
#22
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Year: 1999
Model: Cherokee(XJ)
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Originally Posted by cruiser54
But it will be low vacuum if your booster is leaking internally. The low vacuum will tell the MAP sensor the engine needs more fuel.
02-13-2018, 09:38 PM
#23
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Year: 1990
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Do you suggest I remove the vacuum line from the booster and drive it plugged to see if it runs better? It only backfires and stumbles when driving. I can't get it to when running with no load. The brakes don't do much at all without the booster hooked up, and I'm not sure id even be able to stop it
02-13-2018, 09:56 PM
#24
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Year: 1999
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Originally Posted by cruiser54
Yes. don't drive in heavy traffic.
02-14-2018, 07:12 AM
#25
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02-14-2018, 11:40 AM
#26
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Year: 1999
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Originally Posted by cruiser54
So, you may have more than one issue contributing to the problem......
02-14-2018, 01:00 PM
#27
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Also, I looked at another thread with driving issues and they had a bad egr valve causing a large vacuum leak basically. Might look into that some.
02-14-2018, 01:01 PM
#28
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Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
I haven't gone and tightened the intake bolts, but there doesn't seem to be any vacuum leaks. Idles right at 750 and I haven't been able to locate any leaks. I disconnected the heater valve, but plugged the vacuum line to it. Don't know if it makes a difference, but when I'm on the brakes it idles up and I can hear an air sound and when I let off idle will drop for a second then pick back up.
02-14-2018, 04:16 PM
#30
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Use carb cleaner and spray it in areas you suspect a leak, with the engine running at idle.