stanadyne making truck idle rough?

[The motor guy]

After the last few tanks of my truck having a slight shake at idle, I decided to stop using the stanadyne lubricity formula I've been using since the truck was new and it pretty much went back to idling so smooth you can barely tell the engine is even running. Opinions?

I've heard low cetane diesel fuel can cause rough idle, but what are the chances of getting 3 or 4 tanks in a row?

 

[The motor guy]

I do seem to recall it doing this after buying a new batch of the additive, is it possible they've changed the formula now vs back in 2007?

 

[Nick1994]

Where do you get fuel? Is it at the same station all the time?

 

[The motor guy]

Usually it's murphys which I've never had a problem with, but nobody will change the fuel filter so I quit buying from them. I came back 3 weeks later and it was the same problem. You get idiots will sit their for 25 minutes fueling up their rigs pumping 1 gallon/minute.

 

[The motor guy]

It doesn't make any sense that the lubricity additive could cause a shake right? The last couple tanks I've filled up at Valero since walmart has clogged filters.

 

[The motor guy]

I guess the first step is to just go to a completely different station. I know their is a shell station that I fill up at when passing by that I have good luck with, but I only fill up there if I'm empty and happen to be driving by. No sense driving 5 miles away for fuel.

 

[ArcticDriver]

I have never found any claim that Stanadyne caused rough idle in anyone's diesel.

I am not casting doubt on your own personal experience but maybe ruling out other possibilities is a good idea.

The suggestion to change your diesel fuel source is a good one.

 

[bioburner]

I would checkout couple of the diesel forums for this additive issue. I know I am adding a bit of 2 stroke oil with some diesel service product for my 99 and Shaffers in the old van for decades. Since sulfur has been pretty much eliminated but my area we have at least in the summer a strong shot of biodiesel that helps with lubricity.
Diesel service had a good rebate that a member here posted.

 

[ArcticDriver]

Originally Posted By: bioburner
I would checkout couple of the diesel forums for this additive issue. I know I am adding a bit of 2 stroke oil with some diesel service product for my 99 and Shaffers in the old van for decades. Since sulfur has been pretty much eliminated but my area we have at least in the summer a strong shot of biodiesel that helps with lubricity.
Diesel service had a good rebate that a member here posted.


Are you referring to Power Service Diesel Kleen products?

I fully agree on the bio-diesel and no harm with 5% Bio (B5) although your BioD is probably made from high quality soy and I am not sure the source in TX.

 

[bioburner]

Are you referring to Power Service Diesel Kleen products?


[/quote]
Yes.

I know there is different sources of the bio oil used. I have heard of the use of rendering plant for one source. Even the use of chicken grease. Had a friend plumb a boiler for its use.

 

[The motor guy]

I always was concerned about the lubricity and not the cetane level. The diesel clean ups the cetane, but doesn't do much for lubricity.

Is this why I hear people say that the US has horrible diesel fuel? Frequently buying low cetane fuel?

 

[The motor guy]

I guess the rest now is add some stanadyne and see if the idle becomes rougher