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Discussion Starter #1
2 weeks ago, I had a hi flow cat installed, changed my oil, o2 sensor and shocks.The mechanic didnt hook the air pump back up, either.Truck has been running like a champ. Suddenly, today, she starts running crappy like she was months ago. I have an erradic idle, sometimes around 800, like usual when in gear and on the brake, sometimes as high as 1300 in gear on the brake. When I go to take off, if I give it a small amount of gas, she jumps and jerks. If I floor it, she seems to do ok. My temp gauge has been reading a little hotter than usual, as does my voltmeter. My milage was down to like 8 2 weeks ago, and since I replaced the o2 sensor, seems to be better(like 10). I was thinking EGR valve, but 2 mechanics I talked to, said they've never seen 'em go bad. One mechanic is young, the other is very good at what he does and probably has 25-35 years experience. Any help would be greatly appreciated. I love the bronco, but a year of trying to troubleshoot these various probs is getting old.
 

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On the stock cat, if the air pump isn't hooked up, the cat will clog. Not sure on a hi-flow though.
 

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It's BTW Not AKA!
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So why did you keep cats and the pump, but not hook it up?
 

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IM FAT, YOUR UGLY!
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You should think about replacing your Plugs and Wires and Cap. That same problem was happening to my dads subaru and changing the plugs and wires fixed the problem 100%
 

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Discussion Starter #5
The mechanic that did my exhaust said the air pump was to help the second stock cat do....(?) Said it was not needed with a new cat, I think I am going to take it some where and have them plumb it back in, though. The damn hissing noise is about enough to drive me up the wall. I just did cap, wires plug and rotor, almost exactly a year ago, but that was close to 25-30K ago. I guess that'll give me a reason to go with 8mm wires, and MSD cap/rotor and coil.
 

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It's BTW Not AKA!
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If you have a cat the pump should be hooked to it.
 

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aka: kemicalburns
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the hi flow cats dont need that anymore. if you notice the 96 broncos dont even have a smog pump
 

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any one thought of the Idle air control motor? The iac can stick causing a erratic idle also the computer temp sen can cause it. if the motor thinks its colder than it is it can cause it to go back into warm up. this has nothing to do with the gauge sen on the bronco it has one for the temp gauge and one for the computer. just where I would start looking.
 

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Discussion Starter #9
I replaced the IAC 3 or 4 months ago, but new babies do die everyday. I'll take a look into that. Thanks.
 

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wow, "babies die everyday." My girlfriend would not let me get on here anymore if she read that......gotta go, I just heard her walk in.

SSSSHHHHHH.....everyone act natural!
 

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Discussion Starter #12
No codes come up with a snap on code reader. Time for the old paper clip trick. Temp is still fluctuating, idle is back to normal, and it still occasionally chugs from a slow acceleration from a stop. Also, when I am accelerating, it shifts, bogs way down, and slowly regains rpm's.
And the whole new babies dying everyday thing was from my Autoshop teacher in HS, refering to brand new parts.. just cause they're new, doesnt mean they work.
 

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No codes come up with a snap on code reader. Time for the old paper clip trick. Temp is still fluctuating, idle is back to normal, and it still occasionally chugs from a slow acceleration from a stop. Also, when I am accelerating, it shifts, bogs way down, and slowly regains rpm's.
And the whole new babies dying everyday thing was from my Autoshop teacher in HS, refering to brand new parts.. just cause they're new, doesnt mean they work.
ok did you check your computer temp with the snap on scanner? try that make sure when the trucks warm the computer knows its warm. I run a very low thermostat in my truck and a 4 core rad with 2 fans and when its cold out side I tend to trick my truck the same way making it think it need to warm up. causing the idle to rase then after a sec when it brings the truck up a deg or 2 it chills back down to normal. just a thought.
 

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Discussion Starter #14
Didnt check the temp. I notices tonight when I left work, right after I started it to let it warm up for a few, it was sputtering.. like small backfires. Sounds like a miss maybe. Gonna get the stuff and do a tune-up on it this weekend.
 

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When did you do cap rotor, plugs and wires?

The smog pump puts air into the cat to help it finish the burn better. Fire needs oxygen, so it gets air in there finish the burn in the cat and less crap comes out. This isnt needed for hi flows, IIRC.
 

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The mechanic that did my exhaust said the air pump was to help the second stock cat do....(?) Said it was not needed with a new cat, I think I am going to take it some where and have them plumb it back in, though. The damn hissing noise is about enough to drive me up the wall. I just did cap, wires plug and rotor, almost exactly a year ago, but that was close to 25-30K ago. I guess that'll give me a reason to go with 8mm wires, and MSD cap/rotor and coil.

This may sound like a real nnob question - but - why are you getting a hissing noise/sound ?
 

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Discussion Starter #17
The hissing noise was the air coming out of my air pump. It was still plumbed to the back of my motor, until I pulled the line coming from the pump. I did a tune up a year ago. But, I then pulled the motor out of my wrecked 95 and dropped it into the 92. got probably 25K on the tune-up.
 
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