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Discussion Starter · #1 ·
Can I assume that a CAI lets in more air through the trottle body and at higher speed. I hope I am correct.

Here is my question.

If at very light throttle the plates inside the trottle body are slightly open. Can one assume that the air comming from the CAI might force the plates inside to close a little?
 

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well it allows more air yes
abnd maybe a little faster
but a CAI is really for cold air, and straighting it out, so its nto so turbulant
no because the tilt on the plates, is more then enough to over come the 2 or 3 PSI of air.

the top part goes in the bottom resists... but it works lol
 

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Is the psi constant or does it increase relative to your speed?

it will fluxuate depending on the engines need


its not much at all
3 may be high


its actuly a vacume not pressure but same thing.
 

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Discussion Starter · #5 ·
Well that shoots a hole in my rpm's diagnosis. thanks for the info
 

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why whats up...tell me more!
 

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Discussion Starter · #7 ·
Well after a fuel filter replacement my car runs good enough for a clear description of what I have been dealing with for 4 months now.

My problem happens only when car is warmed up.

If I am flowing with traffic at a constant speed my foot is barely on the pedal. Traffic starts to increase speed so a slight increase on the pedal and my rpm drops from 2k to 1k. Not sure if its upshifting to cause this drop but its really boggy at 1k going 40mph. Once it drops any pedal position from 1/4 to 1/2 throttle produces the same extremely slow increase in speed. Only way to recover from this is to punch it.

Only way to avoid this drop from happening in the first place is hit the gas harder which at times can get tiresome. I am constantly revving high then coast, rev high and coast...over and over again.

Only thing I can deal with on my own is if it were a mechanical problem as posted above.
 

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Well after a fuel filter replacement my car runs good enough for a clear description of what I have been dealing with for 4 months now.

My problem happens only when car is warmed up.

If I am flowing with traffic at a constant speed my foot is barely on the pedal. Traffic starts to increase speed so a slight increase on the pedal and my rpm drops from 2k to 1k. Not sure if its upshifting to cause this drop but its really boggy at 1k going 40mph. Once it drops any pedal position from 1/4 to 1/2 throttle produces the same extremely slow increase in speed. Only way to recover from this is to punch it.

Only way to avoid this drop from happening in the first place is hit the gas harder which at times can get tiresome. I am constantly revving high then coast, rev high and coast...over and over again.

Only thing I can deal with on my own is if it were a mechanical problem as posted above.
Sounds to me like your TPS may be going bad or is mal-adjusted.
 

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Discussion Starter · #9 ·
Sounds to me like your TPS may be going bad or is mal-adjusted.
That is kinda what I am thinking too even though I only have 9k miles on it. But here is where I dont know what to do. When I return every thing back to stock (remove cai and tune) the problem is still their but not very noticeable. With tune and cai...forget about it.... just plain horrible. How would I go about to get this fixed under warranty which runs out Aug 31? Have read many horror stories about Fords warrantys......If the defective part doesnt kill you and 3 other passengers, a bus full of kids, and doesnt take down a couple of planes, trains and skyscrappers...they wont fix it. My first Ford so someone tell me if I am over reacting

Also wouldnt this throw a code?
 

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bight be the tune affecting the shift
 

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tell ford whats up and that you want the TPS reset
 

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Yes the CAI lets in more air. Just sitting in neutral I tripped a lean code when I installed it and didn't do the tune. This also proves the air is drawn in rather than pushed in as I do not have any forced air components. A tune resolved the lean condition.

I don't think there is any affect from driving faster. This is often referred to as ram air. Your filter blocks this effect. Yes the car will draw in more air as I go faster. But if I was going fast and then put the car in neutral so the rpms dropped it would draw in less air then when the car was in gear at the same speed.

The CAI does allow "more air" as a result of the intake of cooler (more dense) air. This was noted earlier by others.

Based on the above I can't see how any of this would affect the throttle plate.

Going to a forced air system could warrant a larger throttle body as the stock throttle body could become a bottleneck.
 

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actually, the increase in air is very slight. The reason a new tune is required is the MAF sensor housing is changed with a CAI, and therefore, the amount of air passing the MAF sensor is different when reading the same voltage. You have to change the tune to tell the computer what readings from the sensor represent what amount of air coming in, so that the computer knows how much fuel to add. If you don't re-tune, the computer sees less air coming in because of the larger housing, and drops the amount of fuel. Since more air is actually going in than the sensor reports, you lean out. You are not actually getting more air, just easing the restriction from the factory air box and filter.

Your TB, intake manifold, heads, cams, and exhaust all would have to allow for more air to really affect the amount of air coming in. Those components are all very efficient on the 3V 4.6 already, which is why most bolt on products don't affect power very much (ie tb's, tb spacers, cat-back exhaust, etc). You can't just change one thing and expect more air to flow unless the thing you replaced was the most restrictive in the system. Most power increase from a new CAI comes from the tune, which really just gives you more timing to take advantage of higher octane fuel.

As far as the OP problem, if your RPM is dropping, it is a shift issue. If the RPM is actually not dropping but you feel a huge loss in power, it could be a vacuum leak or a leak in the intake air tube after your MAF housing. When you push the gas a little, if it is leaning out, you could experience a loss of power, or worse, there might be a slight detonation from the lean condition causing the computer to pull timing, resulting in the engine "bogging" and losing power. If the leak is small, once you get into the throttle more the amount of air coming from it would be small enough to become negligible and not affect anything, restoring power. I would start there..
 

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[...] it could be a vacuum leak or a leak in the intake air tube after your MAF housing. When you push the gas a little, if it is leaning out, you could experience a loss of power, or worse, there might be a slight detonation from the lean condition causing the computer to pull timing, resulting in the engine "bogging" and losing power. If the leak is small, once you get into the throttle more the amount of air coming from it would be small enough to become negligible and not affect anything, restoring power. I would start there..
Yep, check for vacuum leaks.
 

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Don't overlook the seal around the MAF unit itself. One of my screws holding the MAF to the CAI air tube came loose. There was a huge gap and the car was running really bad. So check that as well.
 
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