i need help lol..... iat and ect reading neg 38 deg
02-01-2012, 05:39 PM
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i need help lol..... iat and ect reading neg 38 deg I have a 98 ls1 and I just hooked it up to a snap on modis scanner to check some stuff out and set my tps voltage on the accu fab throttle body and I noticed my iat and coolant sensors are both reading -38 degrees I am trying to figure out if anyone has ever heard of this???
The iat sensor is brand new too...... And if u unplug the sensors the reading does not change
The iat sensor is brand new too...... And if u unplug the sensors the reading does not change
02-01-2012, 05:41 PM
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Also with the engine off and ignition on it was displaying a rpm reading of like 168,000 rpm which seems pretty crazy, I haven't checked it running because I was late for work I'll check in the morning, I do have a autometer Tach and it is acurate when its running so I'm kinda confused with that
02-01-2012, 06:22 PM
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I am pretty sure the scanner is good.... I will try to jump the plug and see if that changes the reading..... The whole reason i hooked it up is because it was running way rich and doesn't want to hot start and after finding this out it makes sense...
02-01-2012, 06:48 PM
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Those temp readings are what you get with an open circuit.
If this is really what the PCM is seeing, then it's not surprising
that swapping sensors helps none.
RPM, though, that's just whacked and says the scanner and
the car aren't speaking the same language.
It's my belief that most hot-starting problems come from a
heat-soaked IAT sensor (made worse by stuff like stock
fan settings, IAT location and so on).
If this is really what the PCM is seeing, then it's not surprising
that swapping sensors helps none.
RPM, though, that's just whacked and says the scanner and
the car aren't speaking the same language.
It's my belief that most hot-starting problems come from a
heat-soaked IAT sensor (made worse by stuff like stock
fan settings, IAT location and so on).
02-01-2012, 06:57 PM
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Thank u that's good to know its from a open circuit ..... Someone told me they were acting like they were grounded out..... And Idk y the rpm is like that because it runs great other then really rich and the Tach works just fine hopefully the scanner will read correct tomorrow when i start the motor....
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02-01-2012, 09:36 PM
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Ok I will try that first thing.... I was told if u unplug them they should change and they did not so I'll jump and check the harness... I am hoping its a loose pin out or a wire
02-01-2012, 09:47 PM
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A bad iat sensor will cause the car to sputter and choke when you give it throttle. I had a bad one I had to replace a few weeks back on my 98 formula.
Also check the coolant temperature sensor in the head on the passengers side. Oreilleys is the only place who carries them for the 98's
Also check the coolant temperature sensor in the head on the passengers side. Oreilleys is the only place who carries them for the 98's
02-03-2012, 05:44 PM
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02-03-2012, 09:28 PM
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I figured it out... The ect sensors I just had to clean the plug and tighten the pins... And for the iat there was a pinout on my ecu #24 and it calls it a (sensor ground jumper) it was not pinned, I pinned it and grounded it now the sensor works...
