Hello: Haven't had a chance to get my 95 F355 Spider into the shop yet and was looking for some insight. When the car is warm and idling the rpm will increase to 1500 to 2000 rpm and the drop back down to the usual 1,000 rpm; and at the same time the check engine light for cylinders 5-8 will come on. Once you're moving and above 3,500 rpm the check engine light will usually go away. On very rare occasions the car appears to idle slightly rough (probably in my mind) when both 1-4 and 5-8 check engine lights are on. Thanks in advance!
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