View Full Version : air silencer

09-09-2005, 07:04 PM
I know this is a dumb question, but how do u remove the air silencer? Ausie u probably know. Thanks in advance.:D

09-09-2005, 09:03 PM
easiest way is to remove the lower part of the air cleaner assy. just act like your replacing your air filter. On the lower part there are a few bolts.. (ten MM if i remember right) take the lower part out of the car. the siliencer is rubber and you can pull if right off the lower assy. reassemble if all back together.

09-10-2005, 09:32 AM
wrenchturner is on the money. But I think the bolt is an 8mm. The easiest way is to loosen up the clamp on the intake pipe at the throttle body and pop the lever clamp on the air box (you will need to unhook the two wire harnes plugs from the air temp sensor and MAF, do not forget to reattach after assembly, and pop out the air breather line to the valve cover) You can lift out the intake pipe complete with the MAF meter still attached. All that will remain will be the air box which is bolted by a single bolt and sits on two rubber plugs at the bottom. Due to clearance issues you basically have to pull the entire assembly out anyway when replacing the filter. Best to have a cotton gause fibre filter than the paper one. Since you have a 99, if you have not changed the air filter yet, this may be a good time to do so. K&N filters ( E-0945) may fit but will be loose in the air box, Fram air hogs (PRA8039) have a better seal but a hard plastic center rim (fits 99 and 01 but not the 04 (due to larger diameter ring that extends out from the MAF mount) , I found that the GREEN high performance air filter (#2002) fit the 04 the best due to the rubber center similar to the paper filters.

The hard way (not recommended unless you are in a pinch: push down on the rubber secion of the silencer on the air box just behind the passenger head light , reach in from beneath the car and get hold of the rubber snorkle from inside the fender well (this is the hard part and will be painful but it can be done but would not recomend it).

What others have done, as well as myself, once the air silencer is out, either keep it for later or it can be modified (cut) just to extend into the fender well slightly to reduce the chance of hot engine air seeping into the air intake. Also note, you will not notice a huge difference except for the slight change in the exhaust note ( a bit more quiet for a short time). You will see a difference in ET's at the drag strip by at least 0.5 seconds. IF you plan on changing the Air filter element to a high flow type listed above it is usually a good idea to disconnect the battery for at least 1/2 hour so the ECU can relearn - remap timming and A/F parameters. At this point you may as well change the plugs too (autolight 764's gapped at 0.050, or what I found to improve throttle response in the 01 denso Irridium IT16 (for 03/04 use IT22) gapped at 0.030). Just a note, if you never changed the plugs on the 4.6 DOHC you will need to get a 12 inch extention with a spark plug socket permanatly attached to it (swivel or rigid), do not use an extention and a separate socket since the socket will remain on the plug once it is set.

At this point it would also be a good time to clean the throttle plate and MAF sensor. Electrical parts cleaner spray will work just fine on the MAF sensor (berryman's Chem-B12 will also do the job) but when cleaning the thottle plate with either a spray or special cleaning solvents designed for fuel injected motors (there are some that come in a can with a giant swab attached) always put a towel under the throttle body to prevent the cleaners from dripping onto the valve cover since they will eat into or etch the paint. Oh yeah, if you are one of those who likes to idle the engine and spray in the throttle cleaner (I am guilty of doing such) make sure the towel or rag is firmly stuffed under the throttle body or it will get sucked into the motor (one reason not to use a paper towel for this approach) and do not over do it or you will vapor lock the motor which could damage internal parts (you would have to be dumping the stuff in mass quantities to do that but it can happen).

And the last item, an oil & filter change.

Okay I took this into overtime. :rolleyes: but it takes care of 4 maintanance items all at once. Probably the best way to take advantage of the time it takes to clear the EPROM memory (1/2 hour minimum). If you have not done any one of these items before, it may be combersome for a beginner and possibly turn into a cluster-&*$%. But once you did any one of these tasks it can be scheduled into your maintanance routine. obviously you would not be changing plugs and the air filter at the same interval as every oil change. Perhaps every 30k to 40k miles or more.

09-10-2005, 05:20 PM
ausie always thorough as usual:thumbsup: I appreciate the info man. I got the idea in the first place after reading about ure drag racing expierience....:D good stuff

09-10-2005, 07:20 PM
<--- thinks assie worls for chiltons in his spare time....... LOL damn bro your like a walking breathing manual for these things.. LOL

good job though your right on the money as usual :)

09-10-2005, 10:12 PM
all you need is a few beers and a hammer:evil:

09-11-2005, 10:32 AM
ausie always thorough as usual:thumbsup: I appreciate the info man. I got the idea in the first place after reading about ure drag racing expierience....:D good stuff
Zobes, keep in mind I am only a beginner at the track so my ET's may be random and not a viable benchmark. If I could dial in numbers that remain consistant then it would be a good basis to apply the mod to the reduced time. What I may be seeing is learning curve development at the track as it seems that just about every pass is an improvement. Also putting in a full day at work on Friday and then going to the track may have an impact on how well I perform. I did have the air silencer out prior to the drag racing experience but put it back in due to the reduced noise from the exhaust. Yeah I am one of those that likes to listen to the sounds of thunder from the exhaust than listen to the radio. I am planning on going to the track this Sunday just to see where my numbers fall in. Also by removing the air silencer and leaving it out completely will allow the hot engine air to possibly enter the intake. I decided to re-install the air silencer but cut down just where it enters the fender. :thumbsup: If you do not want to cut the original snorkel down get one from a junkyard and cut that one instead, just in case you want to put it back on.

Here is where the tangent falls in: (this part can be ignored since my 4rth cup of coffee is causing me to ramble a bit) :cool:

There is an advantage of having a striaght pipe feeding the throttle body but there is also a disadvantage of having the heated air from the engine bay feeding the same especially when you have a compressor that heats the air up even further. Some of the heat will radiate from the radiator and some will radiate up from the headers. The hotter the inlet air temperature the shorter the life of the motor. Air expands when heated so at a fixed volume there will be less oxygen in heated air per unit volume than at a lower temperature at the same atmospheric pressure. In todays modern engines there are 5 basic forms of internal cooling. The obvious is the water to air cooler (radiator), second is the inlet air temperature, third is the EGR recirculation (beilive it or not), fourth is the lubricating oil, and the last is the pressure release of the fuel from the injector into the cylinder. The EGR and fuel evaporation do not provide much and the oil should not be cooled too much, so that leaves the radiator and the inlet air to be the critical means of thermal regulation.