And no I am not the one stuttering

Under throttle... no problems.
Truck runs fine once up to normal operating temps up but....

If I let it warm up just a little..about 5 to 10 minutes..then for the first few miles, when sitting at a light, I can feel a small, inconsistent stutter in the idle. When I go to take off, there is a very slight skip in the accelleration, then it goes just fine. When it does "stutter" or "skip", I can hear the normal engine clatter, for a split second, get a little louder. Then it goes and all is fine again.
If I am at speed, and barely on the throttle to hold the speed, it seems to occasionally have that little stutter in there too. Until it is completely warmed up...then all is good again.

If I let it warm up 15 min or more before heading down the road... No issue at all.

Where do I start?


Thanks all!

 

If you run a cylinder contribution test you should see the stumble. I am guessing you have a grey CPS and it is the cause. #3 & #8 will most always have a higher PERDEL reading with the grey CPS. When I ran one, I could feel it like you mention.

 

x2 on the CPS. A female friend once described my truck as "intense.. like a vibrator."

 

Sheesh...If mine was that good I wouldn't be complaining!

I have a spare in the glove box which is the same as the one that is installed now. I will check it our here shortly. I don't remember of they are the grey ones or not.
But why would this start up like this? It never happened before and I have been running the same CPS for about 3yrs now.

 

Yep... it's the grey one.

 

OK So I have been a bit lazy and finally got around to working on the truck.

So the stutter is still there...just not quite as bad but still there. I did put in my other CPS but it too is a grey one.

I checked Riff Raff and they have the black International CPS but they are sold out. Where else can I get one?

Thanks all!

 

Get one of these from a dealership. Is not the black International one but much better than the grey CPS.

 

I kinda have the same issue- using either the black or newest purple one, it still runs a bit rough- all the damn time. Especially if I hold it around 14-1700 rpms in park, the truck will shake a good amount. Been doing this for a year or so and just can't figure the damn problem out...... seriously thinking about new stick and tuner. Too bad I can't afford to just throw money at it....

 

What CPS is that? Is that the best one out there right now? And what color do we call that one? Looks grey to me.

 

It is a Dark Blue actually.

 

I'm not so sure that it is the CPS. The one it is running now is one that was in there for about 2yrs. I only switched it out last year cause of another issue I had that wasn't the CPS then. It never did it before and this issue slowly started up.
What are some of the other things I can check that could cause this?

One other thing to add... with the warmer weather we have had, it only happened til the motor was up to full operating temps. Yesterday the weather got cold again... high of 40. Well it happened the whole time I was on the road. Even after running for about 45 minutes. So it seems colder air temps are adding to the problem. The air filter is about a week old.

 

I just had something similar and it was the ipr nut . It was loose. Well it actually fell off. Put it on and tightened it and all is well.

 

whats the ipr and where is it located?? i feel my truck is doing the same thing and ordered a black cps from the dealer today. I have the grey oem senser on there now. with changing out the senser there isnt any setups that need to be performed correct?? just take the old one out put the new one in and drive off?

-AJ

 

Correct remove old cps and install new one. The ipr is located on the back of the hpop. Look at the top of the fuel bowl then look below that. The ipr has a electrical connector and a nut. Search the forum for ipr and you should find pics. I am at school and on my phone so can't get pics for you.

 

Injector Pressure Regulator.

HPOP is directly below the fuel bowl.