p&g when cold (fix for high idle when neutral coasting?)

[chrisgerman1983]

When I am p&ging now that it is getting colder my rpm jumps pretty high when I go into neutral. Any tips on how to prevent this? Can you trick the temp sensor into thinking that the engine is warmer then it is?

[nbleak21]

If you are talking about intake temps:

WAI is your best bet.

Putting a resistor in line may also work (depending on how it reads [ie. 5-0v vs 0-5v]) but not recommended as this will change AFR and possibly timing throughout your RPMs and can cause reduced performance.

What intake temps are you seeing when this happens? If you don't have already, grill blocks and a front belly pan will help a bit with those temps.

I know that I've been seeing a 30% increase in idle fuel consumption after warmup (.37gph vs .29gph) so its time for me to do the same.


If you are talking about engine warmup, then a block heater is probably your best bet though grill block and belly pan will help it warm up faster. I've since cleared out enough room in my garage to fit the car in overnight, allowing for 2mi shorter warmup vs staying out in sub freezing temps.