Truck will not run with air cleaner installed
#1
#2
The way you describe it can't be. Your missing something else that's happening.
What, I don't know as there is not enough information to even guess.
.
At idle the throttle plate is already open a small amount via the throttle stop setting to let a 'base amount' of air into the engine.
The computer opens the IAC and modulates it's opening to regulate airflow around the base setting so the target idle RPM is attained as measured by the crank sensor.
A total block of airflow would have to exist to stop the motor.
An air filter would not present this condition unless you covered it with some material that air cannot get through like cellophane.
The mass air meter has a secondary effect on all this.
The air meter measures airflow by sampling a small amount of the total air flow at that point in the pipe.
Look and think about it again.
There are many other connections to the intake manifold that pull a vacuum for other uses such as PCV, EGR,, dash air control functions etc.
Is the EGR being opened and causing stalling etc?
What happens when you open the throttle to allow a large airflow?
Something has to show up other than a filter in place or not causing the lack of idle.
Fuel line pressure falling etc..
Good luck.
What, I don't know as there is not enough information to even guess.
.
At idle the throttle plate is already open a small amount via the throttle stop setting to let a 'base amount' of air into the engine.
The computer opens the IAC and modulates it's opening to regulate airflow around the base setting so the target idle RPM is attained as measured by the crank sensor.
A total block of airflow would have to exist to stop the motor.
An air filter would not present this condition unless you covered it with some material that air cannot get through like cellophane.
The mass air meter has a secondary effect on all this.
The air meter measures airflow by sampling a small amount of the total air flow at that point in the pipe.
Look and think about it again.
There are many other connections to the intake manifold that pull a vacuum for other uses such as PCV, EGR,, dash air control functions etc.
Is the EGR being opened and causing stalling etc?
What happens when you open the throttle to allow a large airflow?
Something has to show up other than a filter in place or not causing the lack of idle.
Fuel line pressure falling etc..
Good luck.
#3
When you say "with or without the air cleaner", do you mean the air cleaner ELEMENT? That you connect all of the plastic air tubing in its proper place and it will not run no matter if the element is there or not, but if you leave the air induction plastic open to the atmosphere were the filter goes, it runs?
If THAT is what is happening, a few ideas:
The air inlet to the filter (is in through the fender?) is plugged, like with a dead rat.
Or there is a major rip/split in the air induction tubing after the MAF, that opens up when everything is in its proper position (in other words, lets in unmetered air).
Or there is an electrical problem with MAF connector or harness, such that a wire opens up when everything is in its proper position.
Or maybe the PVC fresh-air rubber tube connected to the intake tubing near the throttle body has a hole/split in it, and the addition of all of the induction tubing and filter adds just enough restriction that the air in through the leak becomes too much, which would sound like it was just on the edge the way it was.
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