idling rough when cold or fully warmed up, idling rough when cold or fully warmed up Options

[codybellenbaum]

So about two weeks ago i drove 800 miles because i moved to LA. i had to pull a trailer weighing about 2000 pounds all was going well until i went over the grape vine on i-5 cracked the radiator somewhere on the pass then it overheated so i pulled over in la and got towed to my destination (10 miles away) bought a new radiator put it in no problem. took it for a test drive and it ran horrible like it wasnt running on all cylinders. so while it was running i pulled off one wire at a time to see which one didnt make a difference.. i believe the car got so hot it fried all the plug wires because 2/4 litterally ripped in half while i was checking them. so i ran to a part store got new plugs wires and cap and rotor. the car ran great for a day or 2 then one morning it ran the same as it did before i gave it the tune up, but after 10 seconds it ran perfect again. now it does this every time the car is started cold. a few days after that i noticed when its fully warm it runs similar to cold... running rough at low rpms but more subtle when its warm than when its cold. Does anyone know what could be causing this kind of behavior from the engine?

PS. Also the check engine light came on when it over heated the first time when the radiator cracked. i keep forgetting to reset the light. i dont think it has anything to do with the current problem but im not sure because it did happen around the same time..

[Special_Edy]

First I'd do a cylinder balance test, easiest way to do it is to pull the spark plug wires one by one while the engine is running. Each time you pull a plug-wire the rpms should drop so if one cylinder doesnt drop the rpms like the others you know this cylinder is misfiring. If all 4 cylinders are even than we can go from there.


Also, keep in mind that the throttlebody is connected to the coolant system you yoou need to insure that all the airbubbles are out of the cooling system or it might not idle properly.