I have a 2003 Toyota corolla 4 cylinder and it has a bad engine idle shake no codes just replaced spark plugs, cleaned the throttle body, new air filter, it always had a shake at idle but now it's getting worse, all new engine mounts and transmission mounts, runs great after idle, gets great gas mileage, passes smog, any help would be appreciated. Thanks
Have you checked the fuel pressure, the fuel pump may be failing.
Or perhaps the fuel filter needs replacement.
I have a 2003 Toyota corolla 4 cylinder
Mileage?
no codes
That doesn’t mean there aren’t other potential problems. Systems on the car have to be a certain level of “abnormal” before they trip a code.
new air filter,
Did the air filter test as bad?
all new engine mounts and transmission mounts
Did they test as bad?
any help would be appreciated
Try checking live data. Anything suspicious?
A full diagnostic scan for codes and live data would be a good place to start.
does it happen in all gears?
I would test the compression on all cylinders.
