rattling in my 93 teggy
- Thread starter larp
- Start date
rvasquez6089
New Member
mine does that too, i think alot of it has to do with how well tuned up you keep your car and how well it runs, such as replacing the spark plugs, making the sure the air filter is clean,and making sure the timing is right on the distributer. My dad rebuilt the top half of his toyota tercel engine recently and it almost does not shake at all, before it used to shake ALOT. He got a valve job done on it and put it back together. The engine runs strong now, it even sounds like it has its own tuned exhaust note >D. So alot has to do with how well your car can run/idle. My teg shakes ALOT too, i shift it to neutral if i get annoyed enough though but maybe one day i can get the head redone on it too, but right now i don't have a good reason for doing it. He had to do his because the cylinder wall that extends from the cylinder into the head past the head gasket lost a big chunk of metal and then 2 cylinders were leaking exhaust gas, and everything into each other (they basically lost all pressure and obviously busted the HG since the head was busted. im surprised the chunk of metal didn't scratch the cylinder wall or destroy a valve ._. it just disapeared @_@. So do the simple things that i first mentioned, and if you really think its worth it, take the head off and take it to a machine shop to be cleaned, valves reseated, and seals replaced. It will still shake a little, but hey its an old 4 cylinder car with an automatic transmission <------thats the real problem lol >D
Last edited:
rvasquez6089
New Member
now that i think about it it has to do directly with how well the valves are seated because, when you have it in drive and you have the car at a stop, the engine has to run at a low rpm (700) while turning the torque converter. this puts a load on the engine. Since the engine is at a low rpm, the pressure inside the cylinder has more time to escape if the valves are not seated correctly. Since the torque converter is putting a load on the engine, the pressure inside the cylinder is also is under more stress and it has to find the fastest way to expand (which is either pushing the cylinder down or leaving through a leaky valve) , however if the valves are not seated properly or poorly, the pressure escapes more and more through the stroke, to the point that it has probably no pressure at the bottom of the stroke. So at the beginning of each stroke there is this immediate push on the cylinder purely from the ignition of the gas, however for the rest of the stroke there is a significant drop in pressure over time through the stroke. So that happens every time the engine fires. Since the car is a 4 cylinder there is alot of time between when each cylinder fires. So in each piston you get, ignition - strong push from explosion - loss of pressure in cylinder(litte to no push at all). So you every time the engine fires you get this large spike in torque and then a sharp drop of in torque, because the torque converter is putting load on the engine and it slows it down between each time a cylinder fires enough that when it is sped back up it causes the engine to jerk.
Hopefully that was well enough explained and it makes sense. AND i hope i am right, but im pretty sure i am lol good like with your vibrating car!
Hopefully that was well enough explained and it makes sense. AND i hope i am right, but im pretty sure i am lol good like with your vibrating car!