What causes idle speed on fuel injected engine?
Idle speed on a fuel injected engine is controlled by; allowing a small amount of air to bypass the throttle. The most common failure is partial/complete jamming of the actuator (due to dirt/dust or even oil). The result is that it, cannot be smoothly controlled.
Why is my car stalling at idle speed?
Consequently, stalling problems of any kind, are always a challenge to diagnose. The problems that arise from an engine vacuum leak, can be more than annoying. Idle speed, that is way too fast is one of the difficulties, and stalling is another. Confirmation of an engine vacuum leak can be, a very loud hissing sound coming from the engine area.
What causes engine knock on a 4.3L Vortec?
Engine knock can be caused by a ton of factors, such as low-grade fuel, bad spark plugs, carbon build-up, etc. Engine knock is terrible for your engines internals and can cause serious damage to the pistons and to the cylinder walls. On the 4.3L vortec, the cause of the engine knock has not necessarily been figured out, still to this day.
Where is the idle control valve on a Chevy Vortec?
The idle control valve sits on the throttle body and is responsible for adjusting the amount of air that enters the engine at idle, ultimately controlling engine idle speeds. At idle, the valve blocks a small amount of air from entering the engine, keeping idle RPM’s low.
What happens if you have a bad idle control valve?
Since the idle air control valve is supposed to manage the idle speed of the engine, a bad valve will certainly throw that out of whack. It will cause the idle speed to randomly fluctuate to different speeds rather than stay at one constant speed. The idle speed may be too high at one moment and then too low at other moments.
Why does my engine knock when I let off the gas?
Say the clock has struck 5:00 and you make a bee-line to your truck and take off for home. When you mash the accelerator out of the parking lot, that’s when you hear an engine knocking sound. Or ping. When you let off the gas, it goes away. This is likely due to either pre-ignition or detonation.
What happens to your car when you idle?
A rough idle will result in intense vibrations forming whenever your vehicle is stopped with the engine running. Since less air will be going into the engine during its idle state, the car will react by shaking profusely.
What to do when your engine starts to knock?
But you can sometimes address pre-ignition by using a higher octane gas or by cleaning deposits from your engine with a fuel-system cleaner like AMSOIL P.i. Performance Improver. Using a higher-quality oil that flows better in cold weather and maintains its viscosity when hot can sometimes quiet a valve-train tick.