Idle speed irregular

[GLack]

I have several questions about my 2005 Cummins engine idling and maintenance. I bought it brand new from the dealer.The truck tends to sit unused and over the years for several weeks to maybe a month at a time. It has about 70,000 miles total. It has the 6 speed manual transmission, 2 wheel drive. This issue started after about 5 years of ownership. After driving the engine for a few miles, when I take it out of gear and stop, the engine will return to idle BUT the tac show (AND you can hear the engine) 'hunt' for it's normal idle speed. It will go below and then above, then below, the factory set idle speed, repeating this for about 5 to 7 seconds. It never did this in the beginning. (In the last two years the swing while 'hunting for an rpm' is now slightly more pronounced, going a little higher and lower). It will then settle in at about 650 and idle like a swiss watch except for a slight miss every 20 seconds or so. I regularly have replaced the fuel filter myself at or close to 15000 miles. The oil is almost always been full synthetic. The only changes I have done to the motor is an AirRaid reusable intake filter set up. The 'idle hunting' is my primary question, but a secondary would be the '20 second or so' engine miss. Lastly, considering the truck is now 15 years old, what should I be looking at in the form of maintenance or maybe something going out. I did replace the coolant with distilled water and anti freeze about 6 years ago. I also bled the brakes completely and put new brake fluid in about 4 years ago. My son needs me to drive him to South Dakota in a couple weeks to pick up a used IMR plaster pump. We are driving from the last bastion of FREE CALIFORNIA, San Diego.... and I have NEVER been to SD in WINTER...…..but this pump is all he can afford to help him start his pool plastering business. So, we are gonna go get it. 'yippee'. Recommendations for winter driving, vehicle maintenance, and route would also be heeded.

 

[cerberusiam]

Start with changing the FCA (fuel control actuator), that is the electrical connected component on the back of the CP-3. It is the most common culprit in an idle hunt. Time to put together an additive package with conditioned and lube, a perennial favorite is Power Service and 2SO. Mix a quart of 2SO with 96 ozs of PS and put 10-12 ozs of mix per 1/2 tank of fuel every time you fill. Might very well cure the idle hunt also.

South Dakota is a big state, where are you going? Makes a difference in the route I would take this time of year.

 

[GLack]

Start with changing the FCA (fuel control actuator), that is the electrical connected component on the back of the CP-3. It is the most common culprit in an idle hunt. Time to put together an additive package with conditioned and lube, a perennial favorite is Power Service and 2SO. Mix a quart of 2SO with 96 ozs of PS and put 10-12 ozs of mix per 1/2 tank of fuel every time you fill. Might very well cure the idle hunt also.

South Dakota is a big state, where are you going? Makes a difference in the route I would take this time of year.

 

[GLack]

Start with changing the FCA (fuel control actuator), that is the electrical connected component on the back of the CP-3. It is the most common culprit in an idle hunt. Time to put together an additive package with conditioned and lube, a perennial favorite is Power Service and 2SO. Mix a quart of 2SO with 96 ozs of PS and put 10-12 ozs of mix per 1/2 tank of fuel every time you fill. Might very well cure the idle hunt also.

South Dakota is a big state, where are you going? Makes a difference in the route I would take this time of year.

Thank you for the advice. Sorry for the late response, I responded using my phone and I apparently didn't send it correctly. I will try the Power Service and 2SO, though I am not sure what those are. We are headed to the Sioux Falls area. As soon as my son has a new employee 'good to go' for a week on his own, we will head out. Do you recommend chains or...…? I know that is FELONY snow country, coming from San Diego you can surmise my experience on ice was limited to a trip to Biloxi after Katrina via Texas, about 3 hours west of Dallas. Nooo fun. Thanks again.

 

[GLack]

What exactly is '2SO'? Also, Power Service has a couple of winterizing products, not much difference to the untrained eye, is there one better than the other? Also, a lot of people on the net are yammering about "Howes" being manna from the gods. "Lucas" gets bandied about significantly also.

 

[cerberusiam]

Power Service is a fuel conditioner, should be in any parts store. 2SO is 2 stroke oil, not the syn stuff just the normal cheap 2 stroke oil that is commodity everywhere.

This time of the year and depending on weather east on 10/20 and take 20 where it splits in Texas then pick up 35 at DFW area, north to Salina Kansas. You can then go straight north on secondary rods to just outside Sioux Falls or head east and hit 29 either at KC or Omaha.

Cables for slick roads would be a good thing to have. Right now you have to pick your routes as these storms are throwing stuff all over. Ice, snow, rain, and a mix of all can be anywhere for DFW north.

 

[GLack]

Again, thank you for the info and advice.