I have noticed thismore recently now that weather has gotten colder out but I am having a problem with surging and wandering idle. I esp notce it at a traffic light when sitting there with foot on the brakes, it will jump forward a little almost as the computer feels the RPM drop a little and gives it a little shot which makes it lurch a little bit.

I dont notice it as much when i run fuel additive but its still there. I recently did thermo stats because it didnt seem to heat as well as it used to but still bout the same. I had a couple SES lights intermitantly but they would go out after a few times of driving and shutting off.

Any ideas? Could this be the Fuel Pressure Rail Sensor? Anybody have this happen?

one other thing. When you listen to it idle in park, you can almost tell that there is something clickin on and off almost like a drawing down and a governor kicking back in to raise it back to where it is suppost to be. No sound is really heard, just almost like a draw on the motor or something.

It sounds most like a fuel pressure regulator. Surging idle is a classic symptom when these parts start on their way out. Try running 2-stroke oil in your next batch of fuel to see if that clears it up a little. If you want to eliminate it completely, its probably best to change out the FPR. Lots of threads going on this forum regarding the same problem.

Thats what i was thinking too on just what I have read on this site before. What is involved in canging that out? I can do some jobs but not sure i should be thinking about doing that myself or not. How could i diagnose the problem?

I have this issue and I think i am going to need to do the Neutral Safety Sensor on the tranny too and that appears pretty pricy too

is it making a little bit of smoke at idle now? superpros's right 2 stroke premix will help the problem if it is the fpr going bad. check for codes too mine threw a bad fpr code

I have this issue and I think i am going to need to do the Neutral Safety Sensor on the tranny too and that appears pretty pricy too

The NSBU is pretty easy to fix. Get a heat gun to soften up the sealant that holds the switch in place. Good luck.

Wish I had a way to check codes. It has thrown a code a few times in last 2 months since it started getting cold but it will do it once and then after i start the truck a few times it goes away and doesnt come back for quite awhile.

I havent seen any smoke at all with the truck but I will keep an eye out to see if i see any.

How much premix 2 stroke oil? same stuff i have for my chainsaw? Special brand matter? I have the little premix bottles I use to treat my small gas cans. Would i just put one of those into a full tank of fuel? Whats the principal behind that?

I have been thinking of doing the NSBU switch here sometime soon but they seem to be expensive. Anyone find a way to get them more reasonable?

I used to have the surge, 1 oz perr gallon and after a tank or 2, I have not had it for over 3 years!

I used the blue jug from Wally World and I still occasionally use it!

mine surges when its cold to, but goes away when it warms up, basically after about 20 min. Its the FPR, but since the surging goes away, i'm not going to bother changing it yet. Mine also does the same thing when you talked about draw on the motor. Now when I park my truck in these winter months, I'll leave it running if I'm going to be shorter than 20 min. I'll even kick on the high idle. If I leave the heat on, every 10 or so seconds the truck kinda boggs down If you are listening for it. If I turn the heat off, it doesn't do it, so try that.