Rough idle...why
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Rough idle...why
I just replaced the plugs (factory replacements @ .035 gap), new wires. I backed the fuel pressure off a little because I was running rich. Timing is at 4* advanced. What could be causing this? Every now and then the idle will dip and the car will catch it but for the most part it is quit lopey. Mods are in sig. Could this be a faulty EGR, or TPS?
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Car: yy wife, crazy.
Engine: 350, Vortecs, 650DP
Transmission: TH-350
Axle/Gears: 8.5", 3.42
Uh...... what gave you the impression you were running rich?
Did you try returning the FP to where it was? Maybe the engine's running lean now?
Did you try returning the FP to where it was? Maybe the engine's running lean now?
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
My car smells rich and when I chamged the plugs they were fuel foulled. I have a vacuum adjustable regulator on there. I may put the stock one back on and start over.
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Car: 91 Camaro RS Update: Sold Camaro, now own a "91" Corvette.
Engine: Corvette L98 TPI
Transmission: 700R4
Unplug the vacuum line going to the EGR valve and put a golf tee or screw in it and run the engine at operating temp. If the engine runs noticeably smoother the EGR valve needs replacement.
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
I am going to check my EGR. I am pretty sure I don't have any vacuum leaks (I have had them before and know what they are like). I have since drove the car around with the new plugs and wires and decreased fuel pressure and it seems to run a lot better and smoother. It will idel smooth but dip real hard and almost stall. Other than that everything seems to be getting better.
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