97 N/A vacumm?
#1
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97 N/A vacumm?
So I'm playing around with my Scan gauges that I finally made pods for. I have a question on vacuum. I'm pulling around 10.2 mm/hg (or is it in/hg) at idle. I noticed my friends SRT-4 pulls around 20. What is the normal vacumm at idle on an L36?
#2
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IIRC, you should have less than 5" at full throttle and around 20" at idle. Check your lines and PCV.
Turn on The Weather Channel, as barometric pressure does have a small effect on NA engines.
Turn on The Weather Channel, as barometric pressure does have a small effect on NA engines.
#4
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#6
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#7
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True Car Nut
Vacuum diagnositics:
- Average, steady readings between 15-22 inches Hg (normal readings for a 60° V6 engine may be lower, i.e., 12-16 inches Hg) Possible Cause: Normal
- Low but steady, between 12 and 15 inches Hg Possible Cause: Leakage around piston rings, late ignition timing, or late valve timing
- Needle fluctuates or drops between 1 and 2 inches Hg at idle Possible Cause: Burned or leaking valve or spark plug in one of the cylinders is not firing
- Irregular needle drop between 1 and 2 inches Hg Possible Cause: Sticking valve, intermittent spark plug misfire, or rich or lean air/fuel mixture
- Normal at idle speed, but excessive vibrations at higher rpm Possible Cause: Weak valve springs; valves sticking in guides
- Excessive vibrations at idle speed, but steadies at higher rpm Possible Cause: Worn valve guides
- Excessive vibrations at all rpm Possible Cause: Leaky head gasket
- Needle oscillates slowly, or drifts between 3 and 9 inches Hg lower than normal Possible Cause: Intake system leak
- Normal at idle speed, but drops to near zero and rises to lower than normal Possible Cause: Restriction in exhaust system
#8
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