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Old 05-09-2008, 10:41 PM   #1 (permalink)
Master EcoModder
tasdrouille's Avatar
Join Date: Jan 2008
Location: Mirabel, QC
Posts: 1,672

The Guzzler - '08 Hyundai Elantra GL
90 day: 33.12 mpg (US)

Got Soul? - '11 Kia Soul 2U
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Testing the IAT mod

So I decided to give a shot at the IAT mod on the TDI. In fact for this car, it's the FAT mod (Fuel Air Temperature) as we also have a fuel temp sensor to play with.

I used switches so I could toggle the mod on and off without too much hassle.

Here's the resistor attached to the fuel pump harness. Inline on pin 7 in my case. The other 2 wires are bridging pins 2 and 3 with a 1k pot, fooling the pump's piston movement sensor so I can dump in more fuel (hardly useful for FE...)

And finally the IAT sensor which is located post intercooler.

I did a couple of tests run.

Stock timing for the TDI is supposed to be between -3 to 4 at idle and between 8 and 12 at 3000 rpm. My car, as per my SG, was at -1 or 0 at idle and 8 at 3000 rpm, a bit on the retarded side.

With the mod on, my reported timing jumped to 2 at idle and 11 at 3000 rpm.

Here's a very boring video showing what happens when I switch the mod on and off at idle. Basically you'll see the timing switch from 0 to 2 and the temp from 85 F to -15 F when I switch the mod on.

I'll report on FE as I get some data.

__________________ - Quand chaque goutte compte...

Last edited by tasdrouille; 08-21-2008 at 08:42 PM..
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