As most of you know I own a 76' Jeep CJ7 with a 92' 5.0L. IT was idleing at 1200 rpm until I learned from here how to change it. Now it constantely chenges idle, it is idleing "ruff". So, do I need a tune? Yes yes yes I know I have been told to get it tuned but I am affraid of people screwing it up worse. So guide me here, I am lost.
Timing, TPS, IAC, fuel pressure, vacuum leaks, you can do yourself. The O2's need to be read by the computer. Get a timing light, that's easy. The TPS, you'll need a digital multimeter to read it. Vacuum leaks can be found using brake or carb cleaner, and spray along the edge of all the gasket mating surfaces, if the engine changes tone or sound, there's a leak. Fuel pressure, you'll need a gauge to check that and they're not hard to get or install.
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Yup, try setting your base timing to 10* for now with the spout connector to the distributor off. You can probably run more, but lets play it safe for trouble shooting.
Make sure your TPS (throttle position sensor) is readin around .9-1.0 Volts at idle. Check your fuel pressure at the rail with the vaccum line off and engine running. If you have less than 39Psi, you have a problem. Probably need a new fuel Filter or pump.
Remove yout Idle Air Control Motor and clean the area with throttle body cleaner and the needle attached to the motor itself. Re-install and then see if things have smoothed out.
If it hasn't, its time to dig deeper by inspecting all your vacuum lines for cracks or rotted connectors.
If you still find nothing, as said above, spray some carb/throttle body cleaner around your intake gaskets to look for leaks.
If you still haven't found anything, its time to suspect an exhaust leak that would be throwing off your O2 readings.
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2006 Mustang GT in Torch Red
C&L Intake, Evolution Performance Tune, Borla Axle Backs, Hurst Shifter, 4.10's, JBA Long Tubes, Prothane Engine Mounts, Steeda UDPs, FRPP Charge Motion Delete Plates
Okay thanks for the help. I will do these things. Now, he Jeep doen't have Cats, the O2s are plugged directely into the exhuast. Could that be why? I also have changed the idle on it, and it is missing some factory things from the computer. Can any of this have a play in idle?
By playing with the idle manually your only putting a bandaid on it. The idle is all controlled and if its not right, something needs to be changed, not just adjusted. Depending on whats missing from your computer system that may be a factor as well.
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Probe Racing forged and balanced 347 stroker, AFR 185's, Comp XFI stroker cam .579 lift, Parker funnel web intake, MSD Pro-billet mech adv distributor, Scorpion 1.6RR's, bbk full length headers, Canton 7 Qt pan, Flow 40's, Holley 725 Double pumper carb jetted, 125 HP nitrous shot, Full QA1 front suspenion kit, BBk subframe ties, 3.73 rear gears, Barry Grant fuel cell, and no money for a transmission... or paint..
Okay thanks for the help. I will do these things. Now, he Jeep doen't have Cats, the O2s are plugged directely into the exhuast. Could that be why? I also have changed the idle on it, and it is missing some factory things from the computer. Can any of this have a play in idle?
The 02s on a Mustang go in frotn of the cats, directly into the exhaust. So, you are fine.
Depends on what you are missing.
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2006 Mustang GT in Torch Red
C&L Intake, Evolution Performance Tune, Borla Axle Backs, Hurst Shifter, 4.10's, JBA Long Tubes, Prothane Engine Mounts, Steeda UDPs, FRPP Charge Motion Delete Plates
How do I fix my 5.0L rough idleing??? 
