Expert: Sean Halliday - 12/16/2008

Question
QUESTION: why dose my 84 Monte Carlos engine shake a lot in the morning it shakes for a good 10-20 seconds and if i don't give it gas a couple times it will turn off and when i do give it gas it shakes even more so i have to tap the gas pedale

ANSWER: It could be many things.I dont know how often you service the car so it could be in need of a tune up or the result of high mileage.Best way to find out if you have a misfire is go over the complete engine,wires,plugs,cap,rotor.Check the ignition system and then look at the fuel system such as filter and fuel pressure.The engine could have worn valves which will cause low or poor compression until warmed up so a compression test will be needed.I am assuming the engine has high mileage being 1984.

---------- FOLLOW-UP ----------

QUESTION: i change my cars oil about every 2,000-3,000 miles i change the plugs,wires,cap,rotor about every 5,000 miles and when i got it the owner had bought a new block, it only had about 68,000 miles on the new block but the oil was very bad when i got it very black and thick i did a full tune up and it passed the smog

Answer
You will still need to run a diagnostic on the engine because parts do not last forever.Any one of a number of things can fail and cause this.As to which specific part,i would be guessing as there is a procedure for eliminating all good parts until the fault is found.It is too expensive to throw parts at a engine and hope to cure the problem.Possible causes,plugs,wires,cap,rotor,egr valve,fuel filter/pump,coil,distributor,vacuum leak,intake leak, and so on.Best advice is have a shop look at it or buy a haynes manual and look yourself.