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IAT stuck at 46*

Old 08-11-2009, 04:14 PM
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Default IAT stuck at 46*

I have a MS built by Braineck and the AIT is showing 46*F when that is blatantly wrong. I wired it up right to the stock afm harness, but just shows 46*. The sensor is mounted right before the throttle body and the car has only idled for a little.

Is this a firmware issue? I searched for this but all I found where people who's sensors were reading too high and they were fine before.
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Old 08-11-2009, 04:30 PM
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is it stuck at 46*F? is it is just off? Does it change when you unplug it?
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Old 08-11-2009, 04:31 PM
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You didn't solder those wires did you?
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Old 08-11-2009, 04:35 PM
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Originally Posted by gospeed81
You didn't solder those wires did you?
Soldering is for pussies who can't crimp hard enough. No. I need to though.
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Old 08-11-2009, 04:37 PM
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Originally Posted by Braineack
is it stuck at 46*F? is it is just off? Does it change when you unplug it?
The car is away being tuned and I think he figured it out. I will know shortly. It started and just stayed at 46*. I don't know if it changes when he unplugs it. I will have him check that.
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Old 08-11-2009, 04:40 PM
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Originally Posted by rharris19
Soldering is for pussies who can't crimp hard enough. No. I need to though.
I feel the same way...and you're actually not supposed to solder anything that goes to a thermocouple...was making sure that wasn't the problem.
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Old 08-11-2009, 04:40 PM
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the reason i ask is because the fail-safe temp is usually 60*F, but you can look at your matfactor.ini file to see what it states. I think this is a connection issue.
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Old 08-11-2009, 04:44 PM
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Great. Thanks for some direction on where to look. I appreciate the quick response.
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Old 08-11-2009, 05:05 PM
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mine kept unplugging from the hardness and read the same.
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Old 08-11-2009, 07:18 PM
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I had the wires mixed up so it was stuck at 73* for a while. Then i figured out one of the wires was wrong and swapped it and works perfectly.
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Old 08-11-2009, 07:20 PM
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Originally Posted by sbkcocker499
I had the wires mixed up so it was stuck at 73* for a while. Then i figured out one of the wires was wrong and swapped it and works perfectly.
The polarity on these don't matter right? So you connected it up to the wrong wire completely? I will check to make sure it is on the 1 and 6.
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Old 08-11-2009, 07:21 PM
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Originally Posted by hustler
mine kept unplugging from the hardness and read the same.
There is continuity at the sensor from the plug, so i am thinking this is the problem. Either the plug isn't getting a good connection at the IAT or the IAT is bad.
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Old 08-11-2009, 07:27 PM
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I had the wrong wire completely. I had the plug held the wrong direction when finding my wires. 1 sec ill go check what colors they are.
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Old 08-11-2009, 07:34 PM
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Solid black wire

Red wire with green stripe

Cheers!
Attached Thumbnails IAT stuck at 46*-p1010125.jpg  
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Old 08-11-2009, 07:44 PM
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Originally Posted by rharris19
There is continuity at the sensor from the plug, so i am thinking this is the problem. Either the plug isn't getting a good connection at the IAT or the IAT is bad.
check the orange wire on the harness, make sure the solder joint didn't somehow break off.
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Old 08-12-2009, 07:17 PM
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Problem solved. I'm an idiot and hooked the wire up to the 2 and 7, not 1 and 6 at the AFM. I didn't even pay attention to the wire colors because I was cocky and thought "I think I know how to count". I can, just counted them with the harness upside down.
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Old 08-12-2009, 07:20 PM
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Exactly what i did
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Old 08-12-2009, 09:25 PM
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glad you figured it out!
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