ZUKIWORLD Online | Suzuki 4x4 Editorial and Forum

ZUKIWORLD Discussion Forum => Suzuki 4x4 Forum => Topic started by: uki on October 06, 2007, 06:51:33 PM

Title: please tell me were the IAT sensor is.
Post by: uki on October 06, 2007, 06:51:33 PM
Hello everyone i just bought one of those better power and fuel chips off e-bay and i have a 1990 sidekick and i can't find the IAT sensor. can anyone please tell me were it is and or what it looks like.  Thanks.

uki  :-\
Title: Re: please tell me were the IAT sensor is.
Post by: SnoFalls on October 06, 2007, 07:41:09 PM
succa
Title: Re: please tell me were the IAT sensor is.
Post by: Carnage on October 06, 2007, 11:50:51 PM
hmmm
Title: Re: please tell me were the IAT sensor is.
Post by: mrfuelish on October 07, 2007, 12:12:24 PM
I think what they are trying to say is that you would gain more power by rolling up your windows.
Title: Re: please tell me were the IAT sensor is.
Post by: bentparts on October 07, 2007, 02:53:33 PM
It's usually located at the airbox, at least on the 16v airbox.
Title: Re: please tell me were the IAT sensor is.
Post by: 95tracker on October 08, 2007, 08:19:10 AM
On the 16v its on the air box and on the 8v it is located on the manifold right next to the coolant temp sensor by the thermostat housing.
Title: Re: please tell me were the IAT sensor is.
Post by: wezeles on October 08, 2007, 08:22:03 AM
they work for a little extra dont expect your gas millage to get better though... they might have said it would but you will loose some mpg because it just runs it richer all the time... but it helps...
Title: Re: please tell me were the IAT sensor is.
Post by: Rhinoman on October 08, 2007, 11:58:56 AM
they work for a little extra dont expect your gas millage to get better though... they might have said it would but you will loose some mpg because it just runs it richer all the time... but it helps...

It shouldn't run rich for too long. The ECU will correct the fuelling based on the readings from the O2 sensor. Then you're back where you started.
Title: Re: please tell me were the IAT sensor is.
Post by: wezeles on October 08, 2007, 12:17:58 PM
depends what type of "chip" you get... they got the cheep resistors you can get at any radio shack that will tell it to read cold all the time keeping it at the same level... eventually all the other sensors will comp it out... or they do make a real chip that doesnt eliminate the IAT it just translates the signal different inline... so if its telling the motor it needs a 14.8 ratio stock the chip will change that to 12.8 and no check engine light because of the constant signal... its not going to give you butt loads of power and you will have to pay a decent amount for a real chip 25-50 bucks but its not just a resistor... these vehicals were built around fuel economy... you can get more out of them if you change that.. but still best bet would be the basics to start intake and exhaust... then add some more fuel... otherwise your not doing much... mine a tad peppier with a chip but you really notice it on the e-way when going from 60-70 seemed to take forever now it doesnt...  but my mpg is down a couple now because of it... but worth the loss
Title: Re: please tell me were the IAT sensor is.
Post by: Rhinoman on October 09, 2007, 05:02:19 AM
The air fuel ratio is embedded in the ECU programming. The 02 sensor is used to calculate a Fuel Trim value to compensate for engine/sensor wear. The only way to reliably cheat the stock ECU is a proper piggy-back controller. However thats going to cost a lot more than $50.
Title: Re: please tell me were the IAT sensor is.
Post by: brentd27 on October 09, 2007, 08:32:25 AM
Or you could alter the O2 sensor's signal.

The air fuel ratio is embedded in the ECU programming. The 02 sensor is used to calculate a Fuel Trim value to compensate for engine/sensor wear. The only way to reliably cheat the stock ECU is a proper piggy-back controller. However thats going to cost a lot more than $50.
Title: Re: please tell me were the IAT sensor is.
Post by: Rhinoman on October 09, 2007, 11:03:49 AM
Or you could alter the O2 sensor's signal.

The air fuel ratio is embedded in the ECU programming. The 02 sensor is used to calculate a Fuel Trim value to compensate for engine/sensor wear. The only way to reliably cheat the stock ECU is a proper piggy-back controller. However thats going to cost a lot more than $50.

I have seen a 'gadget' on ebay that claims to do this but I remain sceptical. I believe that the piggy back computers do this, unfortunately I don't think its a trivial task. I have the code for the 8V but haven't worked through that part yet, I suspect the 16V uses pretty much the same algortihm. As I understand it:
Off load the ECU drives the fuelling alternately rich and lean by a fixed amount and then measures the time it takes for the o2 sensor to respond. If the fuel trim value(s) is(are) correct it should take the same time to go rich as it does to go lean. If it takes longer to go rich then the fuelling is lean and it ups the fuel trim value(s). If the measured values move too far away from expected then the O2 sensor is flagged as faulty and it reverts to open loop running using default values.
The problem is that the characteristics of the O2 sensor are extremely non-linear, hence the ECU uses it as a simple 'switch'. The aftermarket gauges you can buy average the signal to get a stable (ish) display but the response time with this method would be too slow to allow fuelling control.
Title: Re: please tell me were the IAT sensor is.
Post by: brentd27 on October 09, 2007, 03:36:27 PM
Well, an O2 sensor produces a voltage range between 0 and 1 volts with the midpoint at 0.45V.  The leaner the mix, the lower the voltage.  In normal operation the system is crossing back and forth over the .45V mark rapidly as the computer changes the mix.  If you want your car to run leaner, you could supplement the voltage coming out of the O2 sensor.  Easiest way to do that would be by paralleling in a AA battery and a couple of resistors to make a voltage divider between the ECU and the computer.  Make the resistor adjustable and you can "tune" the system.  If you wan the system to run rich, just stick an appropriately sized voltage divider resistor network in-line with the sensor wire.  If I put a little moew thought into it, I could probably make a tunable O2 offset system that would shift that .45V midpoint of the sensor range richer or leaner.  Wouldn't be all that hard except for maybe finding an appropriately sized variable resistor, but I don't know until I do some calculations.