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IAT #23 and hard mis at speed
Topic Started: Aug 30 2012, 07:43 PM (1,263 Views)
Larryz260
Fresh Fish
[ * ]
Hi all I'm new to this site and have found alot of info here. I'm also new to metro's. Today on my way home on the freeway it started missing real hard like it was turning on and off real fast, at that point the check engine light came on. When I slowed down it stopped but as soon as I got back on the gas it started again. When I got home I checked the code and it came up IAT#23. Would that cause all that. What do you all think :hmm
. Thanks Larry G.
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Larryz260
Fresh Fish
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I thought someone mite have an idea by now. please alittle help here
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Memphis metro


Have you checked the connector plug to the sensor? Its located in the airfilter housing.

When is the last time you did a tuneup of new spark plugs, plug wires, distributor cap and rotor?

I would consider a engine compression test as well if you never have had one done. The car is getting some age on it, if you never have had any major engine work done on it.

The tuneup and compression has a lot to do with how it runs. Make sure those are right first then proceed to locate any other causes of engine troubles.
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clarkdw


Welcome Larryz260.

What BR said and also check carefully clean all the grounds on the rear of the intake manifold.
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Memphis metro


As for testing your iat sensor. Heres how. Set your digital multimeter to ohms on the 20000 ohm scale and connect leads to the two terminals of the sensor located in the airfilter housing. Record the reading. The reading is based on degrees of current temperature. This one is tested and the current temperature is 90 degrees outside. Thus the reading of 1517 ohms on the meter is concurrent with the temperature based on the diagnostic scale of readings given. Post your reading and temperature and I can tell you if your sensor is good or not according to resistance testing results.

Posted Image
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Larryz260
Fresh Fish
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thanks for info. I just gave it a good tune up, plugs, cap, roter, wires and checked compresion it was around 132,135, 129. It acks like a pluged fuel filter. I have got a new one and put it on, the one that was in it looked like factory. I just got the car it has 151k on it, but it does run very good untill it does its thing. I will do the test on the sensor later to day and will post when I get done. I have not got to drive it since I put the fuel filter in it but will let you all know how it goes. Thanks
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clarkdw


Are your compression numbers with wide open throttle?

For comparison of numbers it is done with wide open throttle. 199 is considered normal and 156 is the minimum acceptable according to the Factory service manual.
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Memphis metro


How did the spark plugs look? Any oily? Those compression numbers are low but since you tuned it up, that should allow you to get the most out of it for awhile. Accelerator to the floor when checking compression.
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Vkhelldog
Member Avatar


blue rhino
Sep 2 2012, 01:26 PM
As for testing your iat sensor. Heres how. Set your digital multimeter to ohms on the 20000 ohm scale and connect leads to the two terminals of the sensor located in the airfilter housing. Record the reading. The reading is based on degrees of current temperature. This one is tested and the current temperature is 90 degrees outside. Thus the reading of 1517 ohms on the meter is concurrent with the temperature based on the diagnostic scale of readings given. Post your reading and temperature and I can tell you if your sensor is good or not according to resistance testing results.

Posted Image
This is my test on my iat sensor, it's 35 degrees Fahrenheit... It's bad eh? http://s1341.photobucket.com/albums/o741/Vkhelldog/?action=view&current=C57CEB2B-144C-4417-9061-C943BCAFDBC7-15771-00000C086F0AEEB2_zps3bbfae93.jpg. Ty in advance
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Memphis metro


At that temperature you should be reading between 5000 and 6000 ohms. Was your check engine light on for iat code?
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wizard 03


Imstead of plugging in a DVM, I would suggest waiting for it to freak out again, and then just unplug it. If the engine smooths back out, its the IAT sensor. If nothing changes or it get really weird and intermitten, it could be a wireing problem.
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