IAT sensor relocation
08-06-2009, 12:22 PM
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IAT sensor relocation Has anybody had to relocate their IAT sensor to the front bumper after doing a cam swap and tune?
My car starting running like **** after it warmed up to opperating temp. It would only run bad if i cut the engine off and restart it, but it would only run bad for 20-30seconds, then it would run fine.
My car starting running like **** after it warmed up to opperating temp. It would only run bad if i cut the engine off and restart it, but it would only run bad for 20-30seconds, then it would run fine.
08-06-2009, 04:04 PM
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I just relocated mine, but I put it up under the black
plastic trim where the climate control air (?) slots are.
100F parked in the sun, 90F rolling, 80F after clouds
came in.
Lot better than the 170-180F hot-start I used to see,
hot starts are way better.
But if you tuned for high IAT then lowering it can give
you mixture errors, same as if you tune it cool and
run it hot.
The 20-30 seconds, may mean your afterstart enrichment
is higher than (now) necessary, or just that the idle AFR
has been bent by the relocate.
Do you find the scanned IAT readings, reasonable?
plastic trim where the climate control air (?) slots are.
100F parked in the sun, 90F rolling, 80F after clouds
came in.
Lot better than the 170-180F hot-start I used to see,
hot starts are way better.
But if you tuned for high IAT then lowering it can give
you mixture errors, same as if you tune it cool and
run it hot.
The 20-30 seconds, may mean your afterstart enrichment
is higher than (now) necessary, or just that the idle AFR
has been bent by the relocate.
Do you find the scanned IAT readings, reasonable?
08-08-2009, 06:03 PM
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I moved my iat up into the nose of the car. I switched to a 85mm maf and was using the internal iat but it seemed to heat sink really bad when the weather got hot here this summer.
08-08-2009, 11:07 PM
#6
Has anybody had to relocate their IAT sensor to the front bumper after doing a cam swap and tune?
My car starting running like **** after it warmed up to opperating temp. It would only run bad if i cut the engine off and restart it, but it would only run bad for 20-30seconds, then it would run fine.
My car starting running like **** after it warmed up to opperating temp. It would only run bad if i cut the engine off and restart it, but it would only run bad for 20-30seconds, then it would run fine.
I've relocated mine, but not for the reason you ask. I'd look @ After start Coolant temp enrichment first, then After start Intake Air temp inrichment, then Spark ECT table & Spark IAT table to make sure that there hasn't been higher negative spark changes made during the tune.
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09-05-2009, 06:03 PM
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09-05-2009, 10:05 PM
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I seem to recall reading somewhere else that you wanted the IAT sensor closest to the intake so the fueling is accurate. Although I don't know how much the temp can vary over the length of the intake tract. Some were installing them in the old EGR location.
09-06-2009, 01:06 PM
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The trouble with close to the intake is, it's right in the oven
and the sensor always sees some blend of what's inside and
what's outside the tube; the lower the airflow, the more it
tells you about what's -not- in the pipe. And parked for 10
minutes, fuggedaboudit.
If you have a good cold-air setup then it's a fair approximation
to say your IAT is the outside temp (more fair than saying it
is engine bay temperature, if the setup is worth its price).
If it ain't so, I'd work on making it so, rather than take the
heat.
and the sensor always sees some blend of what's inside and
what's outside the tube; the lower the airflow, the more it
tells you about what's -not- in the pipe. And parked for 10
minutes, fuggedaboudit.
If you have a good cold-air setup then it's a fair approximation
to say your IAT is the outside temp (more fair than saying it
is engine bay temperature, if the setup is worth its price).
If it ain't so, I'd work on making it so, rather than take the
heat.
09-06-2009, 05:08 PM
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I moved mine right under the air filter where the tip is hanging over the edge into the huge hole that goes down in front of the radiator. I extended the wires a little and screwed down a clamp to hold it there and I'm getting much better readings than the one built into my 85mm maf.
09-06-2009, 09:14 PM
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Even in a SD/MAF tune (stock) and in closed-loop, hook up a wideband and you normally just get leaner and leaner as IAT climbs. My personal opinion is that there is some bias or heat soak. Usually that is corrected after a few minutes of driving. Even the 'cold-air' systems suck up a lot of hot air at idle (I have seen 160F)..they do not go ambient until you get to highway speed.
It is all in your application. If that 2 minutes of heat soak does not affect your style of driving..it is no big deal. It is not a lot of fun when drag racing though. So as always, the question is what is really representative of the air coming in the intake tract.
..WeathermanShawn..
