I posted a message similar to this one and no one replied to it. (Subject
"IAT Sensor Mod") I guess no one here knows anything about them. Some
help, huh? ;-) Anyway, the only thing I can tell you is that you don't
have to pay $4.00 or whatever it is on eBay. Go to Radio Shack and you can
buy 5 resistors for 99¢. What you need to do is look in a Haynes manual for
the "normal" resistance that comes from your IAT sensor and then get some
resistors that are slightly above and slightly below. (Because I still
don't know if increasing or decreasing resistance is what improves
performance, but for $2.00, what the hell) All you have to do bend the
resistor into a U shape, unplug the IAT socket, and put one end in each
socket of the connector. Just make sure you insert it firmly so it doesn't
fall out. Then, just secure the end in some way so that the resistor
doesn't touch any metal on the engine. You do not have to touch the actual
IAT sensor. Just leave it as it is...unplugged in its place.
Example. I have a 1990 Honda Civic LX 1.5L DPFI. "Normal" IAT resistance
is between 1k-4k Ohms. I've been using a 5.2k ohm resistor in mine, and it
seems to have beefed it up just a little. However, if you put too much on
it, the Check Engine light will come on and the computer will ignore
whatever resistor is in there and just guess, which means no performance
increase. I have yet to try a lower-than-1k-ohm resistor yet to see of that
definitely makes the fuel/air ratio leaner. My assumption is that the 5.2k
ohm is making it run a little richer. Be advised, however, that in
extremely cold areas where temp is almost always below freezing, this mod
will HURT your performance. Only use this on days where temp is at or above
32º F, or 0º C. On colder days, leave IAT sensor plugged up.
Jon