DIY: Secondary Air Filter Removal

I took out my seconary air filter last night, but I haven't noticed much difference. this is on a 08 Access Cab 4X4 I4. Maybe a little bit of quicker response at lower speeds in first and second gear, but not much else. After reading all the extremely positive feed back over here, I was disappointed that I didn't notice much of a differnce .

 

On the V6, I agree. I didn't notice a difference. However, on my 4 cylinder, I did notice the difference.

I don't think that this modification (or any intake modification) does too much of a benefit without exhaust modification and remapping of the fuel injection. I noticed more benefit out of my cold air intake after I ripped a big hole in my muffler.

 

I guess what bugs me is that alot of people were talking about the huge difference they noticed and made out to be a real big deal, so it was a let down for me when really nothing happened.

 

I guess you missed the thread where I showed the whole I punctured in the front of my muffler by hitting a wood palette in the middle of the highway, huh?

I love my URD intake, but it is mostly for the sound at wide open throttle when I am passing some numb-skull doing 45 MPH in the left lane. I noticed a bit of increase in mileage (probably ~2 MPG) when I actually drive it nicely. However, I don't think that the intake alone is enough to get some real efficiency out of the truck. If I dumped the 265 All Terrain tires, I am sure I could get some better MPG. The intake does little to help the power output for normal driving conditions.


...but damn it sounds good.

 

well, my exhaust on there there as well, doesnt hurt either.

 

From my experience, if you have a 4.0 don't bother with this mod at all. It seems to work better on the 4cyl, although I can't verify that. I did this mod and ran it for a little while. I think my MPG actually was slightly worse? I put the filter back in. It's really no need in wasting you time with this mod.

 

Well pulled it out today. Just for something to do. Typically I get about 30mpg on my drive to and from work about 130 miles aday. I'm more into seeing what I can get for mpg. 08 2.7 reg cab 2wd.

 

can someone please make a fancy guide for the secondary air filter like they did with the 2.7 in line 4 motor? or did someone make one alredy. i cant find it.

 

look at the first page. its with a 4 cyl

 

This statement is accurate. As for all combustion engines, by allowing more air to enter requires a improved flowing exhaust to evacuate it. Likewise, allowing more air leans out the current fuel mixture. For there to be any realized benefit, more air will require more fuel. This tweaking can be improved only within the limits of the power plants design. Every engine has its limitations. Lean power is often sought after, but can be harmful if too thin. Not that you could cause an excessive lean condition with this mod... even if you opened the exhaust at the header collectors and removed the air box completely. An extreme example and certainly harmful, but not from too thin a fuel delivery level.

 

Removed mine just now. Took all of 3 minutes. Un-hook the two clips holding the top of the air box on, cut a slit in the secondary filter and just rip it out. That has to be the most stupid thing I've seen for a long time. Why? You can't tell me there is a benefit for that. Emissions? It's AIR! There is no emissions GOING IN!

I'm sure the government made them do it. Just like the TPMS deal.

 

its suposed to help filter emissions after the engine is already turned off. i really didnt see the point anyways.

 

i have had a 3" lift and 33" BFGs for about 5 tanks now and it droped from ( the best...) 24 mpg to around 17mpg and thats all highway... after removing the secondary and adding a new K&N im getting at best 19 driving all highway around 60mph... around 70mph and a heavy foot its around 17... not the best but it does help... and all the driving is over the mt. hood pass US26 in OR... 4.0 6 CYL 6 spd... seems to work enough for me !

 

Thats it mine is coming out!

 

I beg to differ, removing obstruction will always help at higher engine speeds. Cruising you won't see much difference. But passing or rapid acceleration you'll have a little more top end. That's my experience.

 

I have no experience on the 6 cylinder. A dyno is better proof than anecdote. I missed that he was in a 6cyl. The only benefit I've heard of for a 6 is the supercharger.