How to tune up a optra chevy engine - Optra Chevrolet Cars & Trucks

What engine ?
Engine Controls - 1.4L DOHC
Engine Controls - 1.6L (L91)
Engine Controls - 1.8L (L79)
Engine Controls - 2.0L (L34 GMDAT)

Only 2 and 3 injectors are firing on my Chevrolet optra,I checked and see that there is no injectors pulse on number 1 and 4 injector,can anyone help please

the temp sensor is located on the right side of the engine under the intake manifold on the engine block.

The engine has to be running to drive the ac compressor and the water pump. Are you saying the engine is overheating when you turn it off ?

A PCV valve's a 1 way valve that ensures evacuation of gases from inside a gasoline internal combustion engine's crankcase.------------------------------------------------------------------------------
super mb star

flashing is a severe condition, most cases it is from random multiple misfires, i would get it checked soon.

google firing order diagram for 2004 chevy optra

Fuel injector's

2005 Chevrolet Optra has four available engines: 1.4L (DOHC), 1.6L (L91), 1.8L (L79) and 2.0L (L34 GMDAT).

If you would like a belt routing diagram, it would be helpful if you would mention which of these engines your Optra is equipped with.

It is located on the left side of the engine(frt view) remove the rad hose then the 2 bolts holding the housing to the engine and you will find the thermostat.