Vibration

buick
skylark

#1

I have a 1990 Buick Skylark GS w/ the 3-speed auto. When it shifts into 3rd It’s fine for 1-2 seconds but then the engine seems to drop RPM a bit & makes a deeper sound & starts to vibrate in a pulsating manner. It’s not violent but anything but unnoticeable,especially in the gas peddle. The body also shakes. It struggles up hills & get’s less noticeable as you gain speed. My speedometer work’s but is way off,indicating I’m going much faster but around 45-50 mph it’s very light. It has 103,000+ miles & was told it sat for some time. The engine sometimes run’s good but mostly sputters,especially in park. It would stall occasionally @ a light but that stopped w/ new wires & plugs. In park it will usually start to fluctuate in RPM from normal to near stall,then goes to sputter mode after a moment. What’s up w/ that? Anyone who knows I’m eager to hear from you. Thanks for your time-Karl


#2

With that kind of miles it should have had two or three transmission oil changes by now. Did it have any?

How about some basic maintenance. When was the last time it got new spark plugs, wires, air, and fuel filters?


#3

The previous owner I can’t speak for but I gave it a tranny fluid/filter change a few months ago,it was needed but did little. I also changed plugs/wires the same time,that stopped it from stalling,I also changed the coolant temp sensor w/ improvements as a result but otherwise behaves the same,just not as severe.I haven’t changed air/fuel filters yet. Air filter needs replacement but isn’t horrible. I forgot to mention that until you get to 45-50mph or so it will shift back from 3rd to 2nd when you let off the throttle. The service engine soon light comes on occasionally but eventually goes out,usually when it’s shut off & eventually restarted.