Start up idle

[BANGEREXPO76]

Guys,

When I used to start my truck it would idle up to about 1100 rpm and then slowly idle down within say 15-20 secs. Now it starts and instantly idols down. I dont think that is correct. It seems to be running fine But i dont like that start up. Anybody else notice this or had this problem. Please chime in.

Thanks
Banger

 

[toms89]

There are so many variables that control idle speed I would not worry about it unless you are actually having issues.

 

[01yellerCobra]

Is the weather warming up where you're at? During the winter my vehicles have a higher start up rpm and stay there longer. When it's warmer they don't idle as high or stay there as long. I'm pretty sure my neighbors were happy I'm driving the Expy this winter.

 

[JTKustoms]

Is the weather warming up where you're at? During the winter my vehicles have a higher start up rpm and stay there longer. When it's warmer they don't idle as high or stay there as long. I'm pretty sure my neighbors were happy I'm driving the Expy this winter.

I agree on the weather having a big effect. In the summer mine will drop down below 1000 to its normal idle fairly quickly but in the winter or cold weather it hangs out around 1100-1200 for a while.

 

[BANGEREXPO76]

The rpm goes down directly after start up.
It has never done that whether summer or winter.
I thought it was designed to start up send the RPM to about 1100 then come down.
The truck is running fine but if there is a problem I want to correct it.

 

[toms89]

Has your throttle body or AIC been cleaned recently? If minimum idle air is off it may throw off your idle control.

Could be an issue with the aic valve itself or a faulty sensor if there is indeed a problem.

There is a base idle speed for both drive and neutral. From there it has air adder functions for temp, a/c, powersteering, tranny, etc. and does not target a specific rpm but does have its min and max range.

 

[BANGEREXPO76]

It was a loose hose. The bigger hose that goes to the air intake from the back of the intake manifold was loose. Retightened everything truck starting & idoling rock solid again. Thank guys.