Sup S2KI, my s2000 was tuned yesterday via AEM EMS v2, and the tuner showed my intake air temps.... at idle i saw where it was 155+!!! My mods include ceramic coated j's racing header, passwordjdm intake, and 70mm single exhaust. Also, I live in Texas and it has been 100+ degrees everyday for the past few weeks. I've read high temps are normal, but I wanted to try to lower mine if possible. Thanks for the help!

 

If you have an ap1 I'd say that can be normal on the dyno, as you are reading the temp inside the intake manifold with all that heat trapped around all that metal - the IAT sensor is in the manifold. The engine is running around 200+ degrees. Actual temps rolling down the road would be a bit better than that as you have cooler air entering the password jdm snorkel and cooling off the manifold with open throttle. The intake manifold cools down the longer you drive with open throttle down the road. Once you close throttle the temps shoot up as heat is trapped in the intake manifold and it takes a bit of time to cool it down again.

If you are getting those temps on an ap2, that would seem a bit high to me with a password JDM intake, those temps would be more in line with a stock intake ap2.

Let us know what s2000 you have.

 

04/05 AP2's have the sensor in the same location as the AP1.

 

Sorry I didn't specify. I have 04, so these temps are normal? I have read where people are relocating the sensor, but I'm not actually losing performance or having any issues really. I just wanted to know if it's not normal and if I could do anything to prevent the high temps. Thanks for the help guys!

 

At the back of the intake manifold?

Op do you have EGR blocked off?

 

Yes, at the back of the manifold.

This car does not have an EGR.

 

I have an all stock 2002 and IAT usually reads 50-60* above ambient. Of course, I only look at my scan tool when idling or stopped - as zeroptzero pointed out intake temps will be lower after cruising for a while with open throttle. I think its normal, but it does affect performance - I don't even bother VTECing when driving in 100* conditions because the lack of power just makes me sad lol.

 

Yes, at the back of the manifold.

This car does not have an EGR.
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S2000 does have EGR.

If you have the EGR blocked off with a plate, then that's your problem right there. The function of EGR is to dilute the combustion charge at idle in order to reduce cylinder temperatures. With the EGR blocked off you no longer can dilute the intake charge to lower temperature, you have to enrichen the mixture to use extra fuel to cool your car at idle.

Try to get your A/F ratio around 13.1-12.6:1 at idle and see if that lowers IAT.

 

Okay that helps. I have an ap1 which has the same IAT sensor location as your model. Keep mind that the sensor is picking up heat from the intake manifold , it does not necessarily mean that is the temperature of the air coming into the intake air box, just by the time it gets to the intake manifold the temp is higher. I would say the temps you are seeing are normal, once you get it on the road driving in decent weather you will see more of an improvement in actual temps. I think the ap1 temp sensor setup is accurate for the temperature of the air that is entering the intake ports, the ap2 temp sensor setup is more accurate for reading the temperature of the air going through the air box. I wouldn't bother moving the IAT sensor, not worth the effort.

Probably when you are driving down the highway with open throttle you might end up seeing intake temp readings about 20 degrees over ambient with your intake snorkel'd setup, when you come to a stop and closed throttle you could see temps jump/spike to 50 degrees over ambient , then as soon as the vehicle starts moving again with open throttle you will see temps drop and continue dropping steadily as long as the throttle is open and vehicle speed is over 30 mph. The readings you see will be most dependant on the level of throttle opening and speed of the vehicle, with a snorkel'd intake the more the better.

 

Yes, at the back of the manifold.

This car does not have an EGR.
[/quote]

S2000 does have EGR.

If you have the EGR blocked off with a plate, then that's your problem right there. The function of EGR is to dilute the combustion charge at idle in order to reduce cylinder temperatures. With the EGR blocked off you no longer can dilute the intake charge to lower temperature, you have to enrichen the mixture to use extra fuel to cool your car at idle.

Try to get your A/F ratio around 13.1-12.6:1 at idle and see if that lowers IAT.
[/quote]

The S2000 does NOT have an EGR. It has an air pump, which is not remotely the same as an EGR. The air pump functions at startup when the AFR's are rich to get the catalytic converter up to functional temperatures and that is all (WBO2 will read extremely lean when it is on). There is no exhaust getting routed back into the intake (Exhaust Gas Recirculation). The air pump pulls filtered air from the intake, pre-throttle body, and then runs into the exhaust through the head, completely bypassing the intake temperature sensor.

This is nothing new as many cars these days do this.


Do not run your AFR richer at idle to cool your IAT, it will not help. Your IAT sensor is getting heat soak from being directly mounted to the intake. Richer AFR's at idle will just waste fuel and potentially wash cylinder walls.