I just got a new motor put in my 7 and I am having issue with the idle. It will fluctuate between 800 to 1600rpm. Also, on my commander, I see that my duty cycle on my injectors will be 0% to 9% at idle. It idles well when I first crank up the car when it is cold, as soon as it warms up, it starts hunting for idle and get worst and worst as the car warms up.


I have all new gaskets to the upper intake manifold. Map sensor is in, all intercooler pipings are good. I have went non-seq, so no rat's nest and no vacuum leaks. All couplers are checked for leaks and there are non.


So anyone out there that has this same situation, I need some help ASAP. Thanks in advance.

 

Disconnect the electrical cnnector to the ISC. Unplug all the hoses (including the brake booster, PCV, double throttle, etc...)except the MAP sensor hose. Plug all the exposed nipples. See if it idles normally. If it does then start reconnecting things one by one until your idle problem returns.

 

Have Phil S call Garfinkle, he will you what to do .

 

when mine was doing the same thing it was the lower intake maifold gasket, when my engine was replaced the shop used the old style paper gasket and it blew, and my engine was doing the idle hunt shuffle.............