Mtrhds94Z

A4 'performance mode' button...
http://shbox.com/1/tpbutton_diag.jpg
[from shoebox' site]

Eliminator

Has anybody done this and something bad happened that you could trace back to the resistor?

polcat1p

Yah, i would like to know how to wire it in series also?

TraceZ

If you are going with a smaller resistor in conjunction with the sensor, Just cut one of the 2 sensor wires and splice it in. It doesn't matter which wire.

Piece of cake. Dont forget to run 92-93 octane with the additional timing to avoid pinging.

I've had a 4.7K ohm resistor in mine for months with the sensor completely unplugged, it works great. It gets hot here in Wisconsin in the summer, too.

TraceZ

With your Jet power module, I dont know if this mod will help you. I think the Jet might already alter this reading to the PCM. I'm not sure, though. Can anyone back me up on this?

polcat1p

If you splice in the resistor in the wire, do you have the sensor unpluged. Isnt that the same as just putting the resistor in the end of the sensor?

ibanez6rg

Don't be stupid and do the resistor... move the IAT farther away from the engine and closer to the filter for more accurate readings. The position of the sensor stock is prone to heatsoak and can actually cause slight knock.

TraceZ

There are two ways of doing this
1) unplug the sensor completely and jump the two wires that went to it with a 4.7K ohm resistor.

2) use a small resistor ~600 ohms in line WITH the sensor. To do this, just splice the resistor into either one of the two wires going to the sensor and leave the sensor plugged in.

TraceZ

This is not a stupid mod. Simply relocating the IAT sensor will NOT accomplish the same thing. This may not be as well known of a free mod, but it is by far one of the best.

Relocating the IAT sensor further away from the engine may help insulate it from engine heat, but it will NOT fool the PCM into thinking it is 47 degrees outside and give you full timing advance for more power.

Understand?

MentalCaseOne

More acurate readings of what? the air as it enters the air duct or the air as it enters the Throttle body?

The whole purpose of this thread is to fool the PCM into believing the incoming air is colder than what it is... If you want to be acurate you must have your IAT as close to the TB as possible for speed density. For MAF usage, idealy you would want the IAT inside the MAF so your PCM knows the exact air temp as is crosses the heated filament and can more accurately measure how much energy takes to keep the filament at a given temp above incoming air temp (Z06 MAF).


If you want to Keep the PCM from retarding timing why dont you guys work on the signal from the Knock Sensor? I believe there is a post here that explains how to rig the resistors....

Another thought of mine... If the IAT gets heat soaked and the PCM thinks the air is hotter than it is ... wouldnt it retard the timing instead? someone here said It will cause the engine to knock and ping, that happens when you have too much timing...or bad gass but not when you remove total timing. I dont know how to explain the PCM removing timing and the car detonating at the same time (unless your fuel mix is too lean).
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How to conect in series... ok here it goes... you have two wires and one IAT, Imagine this picture, electricity flows from one wire all the way to the IAT, goes across the IAT and then it returns to the PCM. Now Imagine this path with a series resistor connected to it ready? electricity flows from the PCM to one wire all the way to the added resistor....then comes out of the resistor other end and flows to the IAT, then it flows through the IAT and finally goes back to the PCM using the other wire that remained untouched. got it?

One last thing... you wont feel a thing after you either replace the IAT with the 4.7k ohm resistor or connect the 500 ohm in series resistor... Only way to find out is if you can measure at what point the engine begins to pull timing and then compare one to the other.

sorry for the late reply.

Marvin

Spllouder

great info , one question what does increasing the timing do more performance? iam sort of lose with the knock sensor and retart timming ?

Also what does the A4 'performance mode' button... do ?

MentalCaseOne

I can only tell you what it feels like in my car... Normally my tranny delays the shift in gears when I press the gass pedal...even when I hammer the sucker the tranny has a slight delay before it jumps to another gear, When I activate the performance button the tranny is more eager to shift. The shift happen sooner and a bit more firmly. The car feels more eager to accelerate. Thats all.


Marvin

ibanez6rg

Yea I guess doing what I said would be stupid.

It's not like Fred (Injuneer) has a fast car and would do something silly like this.

A resistor to whack the timing sounds grand.

TraceZ

Here is a picture of the 4.7K ohm resistor installed. Note the cap for the film canister to protect it after installation

http://www.f-body.com/forum/attachme...s=&postid=8872

I've had the mod in place for several years.

The following is plagerized from a moderator on another f-bod board....
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the IAT is responsible for timing advance. Disconnect the IAT harness connector and insert a 4.7K ohm resistor into the harness (fools the computer into thinking a 57º ambient temps). You'll have to clip the resistor a little shorter and bend it into a U shape. After inserting the ends into the harness, I then insert it into a film canister and tuck it out of the way to keep everything clean and protected. This mod will quicken the rate of the timing advance, you'll have to run premium fuel and the throttle response will definately be better. It will negate the power loss experienced when the heat from the engine radiates to the IAT (especially with the SS filter setup) This is almost identical to the SLP timing tricker for substantially more money. You'll expecially like the fact that the first 1/2 of the pedal travel will have a much snappier response.

This mod is dyno tested to be good for 4 - 7 Rear wheel horsepower. FOR ALMOST FREE.

CamaroGuy22

I would like to see that dyno graph.