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IAT Sensor Relocation

XJ_kevin said:
If you want more performance with taht sensor unplug the sensor and put a 9.25K ome resistor in the female ends, it makes the ECM think its 30f outside and richens your engine up.
Click to expand...

I think 30F is a little low, any idea on what the direct relation is to resistance to what the ECM thinks the temp is?
 
IF fiddling around with the sensor IMPROVES the performance, there is something wrong with the engine managment system....if you do this mod to an otherwise healthy system it will DEGRADE performance and waste fuel...there is a REASON the sensor is mounted where it is. Moving the IAT will make it run rich...rich does not promote power gains....and it can cause premature wear to the cylinders.
 
I think you'll find that most fuel management systems run lean at wide open throttle (WOT). This can be disastrous for a modified engine being pushed to its max RPM range during a drag race, so a "hot rodders" trick is to substitute a resistor for the engine temp sensor while at the strip only; otherwise, the engine will run too rich under normal driving conditions. If the ECM doesn't think the engine is warm enough, arround 140*f, it will stay in open loop; not good for mileage or the CAT.
 
MudDawg said:
IF fiddling around with the sensor IMPROVES the performance, there is something wrong with the engine managment system....if you do this mod to an otherwise healthy system it will DEGRADE performance and waste fuel...there is a REASON the sensor is mounted where it is. Moving the IAT will make it run rich...rich does not promote power gains....and it can cause premature wear to the cylinders.
Click to expand...

I tend to agree with this line of reasoning. If by moving the sensor you were actually changing the real temperature of the air then I would feel differently about it. But the air charge temp is unchanged. You are only tricking the computer to run richer than necessary and that doesn't always equate to more power, often just the opposite. If you look up the stock ohm resistance for the IAT at ambient temps vs high temps you will see a huge difference. On a highly modified engine this might be a desirable change, but on an otherwise stock engine I simply cannot see the point of it.
 
If you have a modified engine, the stock SYSTEM will work fine...if it does in fact run lean, it's because the fuel flow capabilities of the fuel delivery system
can't keep up. In that case, an adjustable MAP sensor and/or larger capacity injectors are needed.

Max RPM for a 4.0 is in the 5.2K range...beyond that you need a timing chain and gear set made from unobtainium or unknownmium. Not to mention that a stock head just happens to begin to go past sonic much higher than that.
 
joey99jb said:
Has anybody seen or tried this before?

http://www.angelfire.com/my/fan/IAT_sensor.html

Any improvements in performance?
Click to expand...

That's my write-up. This mod will only work if you've done a bunch of airflow-enhancing mods causing the engine to run too lean at >70% throttle. It might just richen up the engine enough to reduce pinging until you've either swapped in larger injectors or added a MAP adjuster.
 
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