Intake questions....

[anchorshot]

I recently installed a custom 3" intake onto my 2004 Ranger Edge. Instantly the engine light came on. It's just running lean is what I originally thought. Now it's stumbling alot especially right when I start it up. I have reset it by taking off the battery. Also, when I spin the RPM's to around mid 3000s the light starts to blink. I don't know what is happening.

Also I was wondering what the tube going from about the center of the intake tube to the head of the engine is for? It splits off from the intake.

Thanks in advance for all input and advice.

 

[partsguy84823]

That tube in the center of the intake is an oil breather, you either need to hook it back to the intake, or plug the hole in the intake tube, and then put a breather filter on the oil breather. That will fix your problems, you're allowing the engine to get air from after the MAF, through hole in the intake, which means that the computer doesnt know about that "extra" air. Unmeatered air will cause high idle, rough running, and a lean condition.

 

[Bob Ayers]

The problem is the reduced air velocity from the increased diameter intake. You won't get any more air, just the velocity of the air is decreased, which screws up the MAF sensor measurement.

Put the OEM setup back on, and this will solve the problem.....your performance increase will be due to your lightened wallet!

 

[ForOffRoadDriving]

if all your looking to do is run a cone style clamp on filter then you will need to make an adapter to hook the filter to the MAFsensor, or drill a hole into your 3" intake tube and install a hose barb of the appropriate size so that you can hook the breather back up. unless you have done some performance mods (NOS stickers dont count) then you wont really gain any extra power from the filter, just noise and the posibility of stranding yourself when you hit a big mud puddle and it soaks your filter.

 

[partsguy84823]

The problem is the reduced air velocity from the increased diameter intake. You won't get any more air, just the velocity of the air is decreased, which screws up the MAF sensor measurement.

Put the OEM setup back on, and this will solve the problem.....your performance increase will be due to your lightened wallet!

I agree that you won't see any increase in performance, but it will not cause the problems the OP described. An engine, and the computer atched to it don't care about velocity to run, they care about volume, and his engine is allowed to get a greater volume of air, through the hole in the intake tube, that the EUC doesn't know about. The computer is working hard to keep fuel ratios right at stoich. If the computer thinks it is getting x amount of air, it will provide y amount of fuel. If it is actually getting x+1 amount of air, but the computer still only gives y amount of fuel, you are then running lean, reguardless of velocity.

Ontop of that, any velocity gained or lost by changing the dia. of the intake tube will be negated once that air hits the intake manifold. If changing the air velocity before the intake manifold made much of a bit of difference, TB spacers would work too.

 

[ForOffRoadDriving]

I agree that you won't see any increase in performance, but it will not cause the problems the OP described. An engine, and the computer atched to it don't care about velocity to run, they care about volume, and his engine is allowed to get a greater volume of air, through the hole in the intake tube, that the EUC doesn't know about. The computer is working hard to keep fuel ratios right at stoich. If the computer thinks it is getting x amount of air, it will provide y amount of fuel. If it is actually getting x+1 amount of air, but the computer still only gives y amount of fuel, you are then running lean, reguardless of velocity.

Ontop of that, any velocity gained or lost by changing the dia. of the intake tube will be negated once that air hits the intake manifold. If changing the air velocity before the intake manifold made much of a bit of difference, TB spacers would work too.

i completely agree

 

[Bob Ayers]

I agree that you won't see any increase in performance, but it will not cause the problems the OP described. An engine, and the computer atched to it don't care about velocity to run, they care about volume, and his engine is allowed to get a greater volume of air, through the hole in the intake tube, that the EUC doesn't know about. The computer is working hard to keep fuel ratios right at stoich. If the computer thinks it is getting x amount of air, it will provide y amount of fuel. If it is actually getting x+1 amount of air, but the computer still only gives y amount of fuel, you are then running lean, reguardless of velocity.

Ontop of that, any velocity gained or lost by changing the dia. of the intake tube will be negated once that air hits the intake manifold. If changing the air velocity before the intake manifold made much of a bit of difference, TB spacers would work too.

The air velocity coming across the MAF is extremely important!

 

[anchorshot]

Will running it lean cause a rough idle?

 

[partsguy84823]

The air velocity coming across the MAF is extremely important!

Our trucks use a hot-wire MAF, it works by heating a wire, the more air (higher volume of air) that passes over the wire (no matter how fast the air is moving), the more the wire is cooled. The computer measures the current required to keep the wire at a set temperature, and thereby can measure the of air that the truck is taking in.

Now if our trucks used a vane-style, or a karmen-vortex style MAF (which rely on the velocity of the intake charge to estimate the volume of intake air, I would agree that this could be the problem.

Anyway to the OP, no, a lean condition in itself will not likely cause a rough idle, it will cause a high-idle though. However, if a truck were trying to compensate for a lean condition, or "guess" the amount of intake air, it could cause a rough idle. I know when I seafoam my truck, I pull the vacuum line off of the bottom of my TB (causing a massive vac. leak), it sounds like it is cammed.

 

[anchorshot]

Ok thanks guys, when I get home tonight I will throw back on the old unit and see if this resolves my issues.

Thanks for all of your input.

 

[Bob Ayers]

Our trucks use a hot-wire MAF, it works by heating a wire, the more air (higher volume of air) that passes over the wire (no matter how fast the air is moving), the more the wire is cooled. The computer measures the current required to keep the wire at a set temperature, and thereby can measure the of air that the truck is taking in.
.

If the velocity of the air is increased going through the MAF element orifice,
by definition, the volume of air passing over the element is increased, if the
velocity of the air is decreased, then the volume of air passing over the element is decreased!

 

[partsguy84823]

If the velocity of the air is increased going through the MAF element orifice,
by definition, the volume of air passing over the element is increased, if the
velocity of the air is decreased, then the volume of air passing over the element is decreased!

Ah, I found the problem, you have an engineering degree, I have an engineering degree too... I believe that the combination of our bullheadedness engineering minds are going to keep us from ever agreeing on this, so I think we should stop. I will say though, I understand what you are saying, and you are correct, however I do not think that his problem is MAF related. I think if he puts the stock air intake back on, and leaves the oil breather unplugged, he will have the same problem.

 

[cbxer55]

I have had a three inch MAC on my truck since I bought it. It has never given me a lick of trouble. Idles great, runs great.

Even though my truck is giving me some starting troubles, I put the stock intake back on just to see if it would solve the problem. NO DICE! Same problem, with or without the stock intake.

Oh, and where the bigger diameter pays off is when the rpms rise. Man the sucker just pulls harder and harder as the rpms rise. The stock intake SUCKS!

I would throw it away, but it occasionally comes in handy to test things when a problem does hit. So far, putting the stock intake on has not solved any of the problems I have had.

I have replaced all of the sensors, put in new plugs and a new fuel filter. My truck still persists with a starting problem. But a shot of ether in the breather hole while holding the throttle full open, it starts right up and idles perfectly.

My fuel pressure is perfect at around 62 to 64 psi, running or not. It does not make any difference how many times I turn the key on and let the pump build pressure.

But the MAC intake is not the problem, and anyone who tells you it is has not tried one. Of course, I also have a cat back dual exhaust and JET chip on the ECM.

 

[Tader82]

ok u need to pull the MAF and clean it, as a FORD TECH i have seen this time and time again and my little brother is a TOYOTA TECH and he sees it all the time the oil used in the AIR FILTER will soak the MAF sensor and cause all the probs u have listed. and to the two engineers, both r right, but For a Ford MAF its not velocity meter its AIR Density which is = to air temp, (hot air is Less Dense which = lease Volts to keep wire hot/Cooler air is More Dense which = More Volts to keep Wire hot). If u clean it and still have the prob go get and diff MAF out of junker or a friends 3.0L to test to see if the sensor is bad, u can burn them out over oiling the filler


Bad Kitty Engineering (B.K.E.)
Owner: Whitney

 

[cbxer55]

Actually I do not even use an oil type filter. I use a Spectre filter with stainless steel mesh element.
http://www.sfxperformance.com/parts/SPT9735.htm

With an AFE filter wrap over top for better filtration.
http://www.ajusa.com/details/AFE-28...33439?pq=1&vc=AFE&pn=Pre+Filter+Wrap&vq=null&

Man, you should hear the hiss at idle. Ant the full throttle song is eye-opening.