First I'm assuming that when you say the key is in the "on" position that you mean the car is running or trying to start it. I also must assume you mean you hear a loud bang when its running or your trying to start it. (Lots of assumptions, because you description is weak). Anyway...in order for the fuel to ignite in the intake side of the engine one of two conditions must exist...an intake valve must be in the open position when the spark plug fires during the compression stroke (remember there are four strokes in a 4 stroke engine; intake, compression, power and exhaust). The first way this can happen is if the engine being out of time, and hence needing to be re-timed during a standard tune up, the second way this can occur is if an intake valve is stuck open or is completely blown. A blown valve never seats properly allowing the spark to ignite fuel before it makes it to the cylinder. On older vehicles with carbuerators , when this happend , flames would shoot out of the top of the carbureator...pretty impressive show. I suppose with todays cars the cars computer designates the firing and timing of the spark plugs so that could be the cause here as well.
On the air intake filter box
Under the intake manifold
The throttle position sensor on a 1997 Chevy Venture is located next to the air intake hose on the Electronic Fuel Injector (carburetor). Follow the air intake hose from the air filter to the EFI (carburetor) and it will be on the right hand side where the air intake hose connects to the carburetor.
you have to remove the intake to get to them.
on intake manifold
No on intake, 1 for each cylinder.
To much nitrous injected into it .
It is inside the upper intake manifold. It is attached to the fuel injector poppets with a bracket. To inspect/replace you must remove the upper intake manifold.
The fuel injector would be located on the fuel rail up under the intake manifold towards the side of the engine.
It is located under the upper intake manifold. The bank of injector poppets are also known as the spider.
It is located under the upper intake manifold.
To remove the cover box to get to the fuel injector on the 2002 Envoy, first remove the intake manifold and the valve cover. You can do this by loosening the four bolts that hold the intake manifold first.Ê
Take off the upper intake, the regulator is on the backside of the fuel injector unit spider.
This is often the result , in fuel injected cars, when there is an intake manifold vacuum leak ( i.e. loose or disconnected vacuum line, intake gasket leak , injector seal leak or many other possible leaks in the air intake system ). It is also a symptom of a faulty or maladjusted throttle position sensor.
Cracked intake manifold...
inside the intake attached to the injector module
Normally from an engine backfire. The plug fires when the intake valve is partially open which will explode the fuel in the intake and carb.
It hooks up to the Injector Rail where the injectors are inserted into the Intake Manifold.
Right under the intake manifold with the raised "3400" on it
There should be 8 of them (if you have a V8) they should be attached to the Intake on top of engine.
There are six injectors. They are under the upper intake manifold.
Removing the upper intake manifold will gain access to the "spider". It is not necessary to replace the complete "spider" if there is only one bad injector. Each injector and the pressure regulator are replaceable.
Answeron the injector rail...follow the fuel hoses from the tank to the enginedThe Regulator it under the upper intake on the injector
The fuel injector is located under the air-cleaning unit in the engine. The air-cleaning unit is held in place by 3 nuts, once loosened the unit lifts off to expose the injector and air intake manifold.