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      09-28-2024, 08:33 PM   #1
ohfrnoway
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rpm bounce

my rpms started to bounce, when the ac is off and the car is idling the rpms will drop a few hundred rpm then bounce again but worse bc it bounced
for example if i have my ac on my rpms sit at about 5/600 which is normal
but if i turn the ac off it drops to 500 flat then will bounce to 450 then rise to 600 then sometimes it will be worse and drip to 400 to 650 and if i leave it the car will shut off, i replaced the vanos solenoids and sparkplugs and soon the ignition coils not sure of what it could be, if it was the opposite case and the rpms bounce with ac on it would be the ac compressor but its not, it practically relies on me to be driving or ac on to be stable
any ideas will help me brainstorm
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      09-28-2024, 11:08 PM   #2
Three_thirty_I
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Quote:
Originally Posted by ohfrnoway View Post
my rpms started to bounce, when the ac is off and the car is idling the rpms will drop a few hundred rpm then bounce again but worse bc it bounced
for example if i have my ac on my rpms sit at about 5/600 which is normal
but if i turn the ac off it drops to 500 flat then will bounce to 450 then rise to 600 then sometimes it will be worse and drip to 400 to 650 and if i leave it the car will shut off, i replaced the vanos solenoids and sparkplugs and soon the ignition coils not sure of what it could be, if it was the opposite case and the rpms bounce with ac on it would be the ac compressor but its not, it practically relies on me to be driving or ac on to be stable
any ideas will help me brainstorm
What else have you checked? Something always inspect when you have anything funky going on with rough idle is the eccentric shaft sensor. If there's oil leaking into it, which could simply be the gasket, but can also be the sensor itself that has developed a fracture where it fits inside the valve cover. MAF sensor might need a clean, injectors could need a clean. Start with the simpler things and work your way in.
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