My 90 Caddy (4.5 liter- 98K) has a slight hesitation when I accelerate from a stopped or slower speed. It is most noticeable from a stop and quickly disappears as the car picks up speed – within two or three seconds. I have no codes, and the car has no other symptoms and has been serviced regularly. This hesitation is also accompanied by a slight shake – as though the car is stumbling. Any suggestions on how to troubleshoot? Don’t want to throw money in the wrong direction. Thank you for your help!
There can be a 101 different causes for your hesitation problem. Here are a few that you can start looking for:
Possible vacuum leak - look for disconnected or broken vacuum lines
Dirty throttle body - spray with throttle body cleaner.
Malfunctioning EGR valve - remove, clean and replace gasket
Worn ignition wires / plugs / distributer cap - check and replace as needed
Low fuel presure - check filter / pressure from pump / fuel pressure regulator
Really dirty air filter - remove and replace if necessary