QuestionQUESTION: this only has 78,000 miles it misses at about 40-60 i tried something i read that you told someone to lightly applay brake and see if it still misses ,to check for a overdrive problem when i do this the rpms go up is this what you mean please help thank you
ANSWER: YES.
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QUESTION: how do i find this overdrive is this a cadillac issue or transmision shop type problem ,vaccum fuse,?iam at a loss thankyou for your help its much apprecated
AnswerWhen you lightly apply the brake pedal and feel the bump and the rpm's increase this is the over drive disengaging. Once you release the brake pedal within a second or 2 you will feel another bump and the rpm's will drop. This is the over drive re-engaging.
This is how it is supposed to work.
When the over drive is engaged any slight abnormality in the engine performance such as an intermittent spark plug or plug wire failure or EGR problem will be felt MORE when the car is in over drive and may not be noticeable or severly reduced when NOT in over drive.
Your issue is most likely NOT transmission but engine electronics as said above.
