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I have installed an IAT2 temp sensor and gauge because my L61 doesn't have an IAT2 sensor so I can monitor post charge temps. There doesn't appear to be any smoothing or manipulation to the signal, it has fast refresh rate and I hardly ever read a constant number. I'm not sure if there is any smoothing with the stock LSJ sensor or not so I can't say if it is directly comparable or not. The sensor, module, and gauge brand are all PLX. IAT2 sensor installed opposite side of the stock location because in the stock location my sensor wouldn't clear my fuel rail
Anyway onto my question. Sometimes when I am in a fairly high RPM decel I notice the temp spike to values over 200 degrees. I'm assuming the heat is back-flowing from the head somehow. Or could it be my PCV? Nothing real important I was just curious if anyone knew what could be happening.
It is not intake air that is causing the fluctuations. My regular IAT2 temp has been hovering around 60-70 degrees. Towards the end of a sustained pull I am hitting about 110-120 degrees. The high temp spike only happens during deceleration at higher RPMS and it spikes but will go away as soon as I start cruising again. It doesn't ever do it while I am on the gas. I just don't know where the hot air is coming from.
Could be hot air going back into the intake when in DFCO (Deacceleration Fuel Cut Off). There should be enough pressure to prevent the hot air from being pushed back out of the combustion chamber and into the intake during DFCO, but maybe not. I can't think of any other reason you would get a spike of hot air during decel.
12-23-2016, 09:19 AM
