IAT Sensor issues? Ideas?
IAT Sensor issues? Ideas? My car (97 Z28) has been running rough while I am at stop lights, you can feel and hear it misfiring. I forgot to plug the IAT sensor in and it ran better! It was still misfiring a little but it was 95% better than it was before. Should I replace the sensor? Or is this causing it to bypass the MAF sensor? Any ideas or suggestions would be great! Thanks in advance.
TECH Veteran
Joined: Dec 2008
Posts: 4,146
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From: Little Rock, AR
Unplugging stuff is an inexact way to troubleshoot. It often leads you down the wrong path. The computer compensates in many ways when things are not working, so cause and effect is not always apparent. Monitor the IAT with a scanner to see if there are any problems with it. It can also be looked at with a meter, but a scanner is the better way, IMHO. Everyone needs a way to scan, anyway, if you are going to do your own car work.
Unplugging stuff is an inexact way to troubleshoot. It often leads you down the wrong path. The computer compensates in many ways when things are not working, so cause and effect is not always apparent. Monitor the IAT with a scanner to see if there are any problems with it. It can also be looked at with a meter, but a scanner is the better way, IMHO. Everyone needs a way to scan, anyway, if you are going to do your own car work.
So I narrowed it down a little bit after I plugged the sensor back in. When I sit at a stop light in drive it misfires a little bit, once I put it in neutral it no longer misfires. Any ideas?
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Joined: Apr 2008
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from this side of the internet we can "guess" assuming "your" interpretation of what is happening is accurate
a "misfire" would be associated with ignition, not a IAC. So if you have a misfire under "load" (idle in gear) but it seems to diminish when you put the car in neutral it "could" be a plug wire or boot arcing....but with that said it could be many things also.
on computer controlled cars you need scan software or at least a code reader to diagnose wtf is happening
IAC (idle air control) valve can get dirty so it and the TB passage needs cleaning. Typically IAC problems are idle issues relative to either a low or high RPM.....but you state "misfire"......unless you meant "erratic idle, stumble".
a "misfire" would be associated with ignition, not a IAC. So if you have a misfire under "load" (idle in gear) but it seems to diminish when you put the car in neutral it "could" be a plug wire or boot arcing....but with that said it could be many things also.
on computer controlled cars you need scan software or at least a code reader to diagnose wtf is happening
IAC (idle air control) valve can get dirty so it and the TB passage needs cleaning. Typically IAC problems are idle issues relative to either a low or high RPM.....but you state "misfire"......unless you meant "erratic idle, stumble".
