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Old 11-15-2010, 12:36 PM   #1
Join Date: Nov 2010
Posts: 63
Failed emissions/very poor idle/O2 sensor?

Guys got a '90 wrangler Islander from the old man and tried to pass emissions last week. I passed everything except the NO (PPM) at the 25 mph test (1807 allowed score 2536). I was told the catalytic converter needed to be replaced. I bought and installed this weekend but still seems to be running really rich. When I dropped the kid off at school today I notice the Cat converter was red and hot. Obviously this concerned me so I parked it. I don't have deformities to the converter so i'm thinking it's probably okay.

I've read this means fuel is getting into the converter instead of firing off in the engine like it's supposed to. My question is could it be the O2 sensor not working causing it to pump more fuel than is needed? I've replaced and checked all the plugs but haven't replaced the cables or distributor cap.

I could really use some help since I need this vehicle to get around town. I don't have a ton of money so I don't want to take it to anyone so your help will be greatly appreciated. Thanks a ton in advance.

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Old 11-15-2010, 12:39 PM   #2
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I also forgot to mention it was idling poorly and rough and engine killing if I let RPM's drop too far. I adjusted the choke a little and it helped with the idle some but is still running a little rough. Thanks again

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Old 11-15-2010, 03:52 PM   #3
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Location: Scottsdale,az
Posts: 11
Do the nutter and you should pass with flying colors. If the carb is shot check out the 2100 kit on ebay and your jeep will be running like a champ..
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Old 11-15-2010, 07:37 PM   #4
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The 02 sensor has to be replaced at 88,500 miles anyway.
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Old 11-15-2010, 09:37 PM   #5
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Scott124 can you tell me what the nutter bypass does? I had someone suggest it to me once but they didn't explain why.
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