Hello,

Doing some PM to my 96' 150 with the 4.9. On other engines I have seen the accordion style plastic intake tubes split open after much age, heat and vibration. Remember, its climbing on 20 yrs here. I look at this particular one and notice it stays at a somewhat hard angle all the time into the MAF before the airbox. I feel like any time i change the air filter, i'm going to end up cracking it.

There is nothing wrong with the mounting, everything is correct, I just see it an area where eventually I'll be driving and pirate air will cause me to have to pull over or leave me stranded if I don't have duct tape.

I'd like to simply replace the intake tube with a nice molded setup. I mean, why not? Might even be smoother flow! Unfortunately I don't see any out there dedicated to the 4.9. I could rig something so I wonder what sizes might correspond. Ideas?

 

If the leak is upstream of the throttle body / MAF sensor I do not think it would cause your vehicle to stall.

 

True, it might not stall or die completely, but they'll be some big-time power loss.

Where this hole would start is upstream of the MAF but downstream of the TB. If it were AFTER the TB, say, in the manifold, the idle would race and then it would be termed a "vaccum leak" and not "pirate air." If it is a MAP system, its as if you just opened the plate and the idle just raises the respective amount, no dire problems. This is because the pressure of the manifold is monitored rather than the amount of airstream. On the "Manifold Absolute Pressure" systems, if you broke open an intake tube before the TB, the worst case would just be unfiltered air.

I've had the pirate problem it on a handful of MAF style cars if the tubes open up (which happened on my ranger of similar age, with THICKER plastic accordions) or even when I forgot to secure the clamp once on a Volvo. (this was a turbo and once the boost peaked, it would fall flat on its face, maybe a big rich condition from sudden lack of air in that scenario).

So in conclusion on my 150 if the sensor can't see all the air going toward the throttle body, the system will not fuel as much as necessary and cause a big ol' lean condition. Not good for business. And I feel it could all be avoided with a bit of cheap preventative engineering.

I have read thru another string of posts about intakes and people have alluded that the 7.5 plastic tube is the same as the 4.9. I'm sure to find a good rice rocket tube for the 460 if I can't for the I6...right?