Intermittant rough idle

[cwharding]

Like the title says, my PS idles rough from time to time. Noticed it recently. I drained the fuel filter but didn't notice any water and it still idled funny after. So last night I bought and added powerservice to the fuel. I've never added conditioner before although I add a quart of 30W non detergent every tank. I drove the truck last night and the idle was smooth but I didn't drive it very long. Any known problems like this that it needs to go to the dealership for?

Thanks,

cwh

[Greenhorn Diesel]

Originally Posted by cwharding

Like the title says, my PS idles rough from time to time. Noticed it recently. I drained the fuel filter but didn't notice any water and it still idled funny after. So last night I bought and added powerservice to the fuel. I've never added conditioner before although I add a quart of 30W non detergent every tank. I drove the truck last night and the idle was smooth but I didn't drive it very long. Any known problems like this that it needs to go to the dealership for?

Thanks,

cwh

Could be the EGR valve, or AC cycling But I doubt you have the AC on

[cwharding]

Well, took a drive this weekend for almost 300 miles. I havn't noticed the idle issue but sometimes at part throttle when cruising down the road (50 - 60 mph) it feels like its surging. Maybe it's in my head, I don't know. I did check my mpg's this week and I got 18 mpg all highway. My gauge reads dead on with the hand calculations, like less than a tenth off.

Thanks,

cwh

[Greenhorn Diesel]

Originally Posted by cwharding

Well, took a drive this weekend for almost 300 miles. I havn't noticed the idle issue but sometimes at part throttle when cruising down the road (50 - 60 mph) it feels like its surging. Maybe it's in my head, I don't know. I did check my mpg's this week and I got 18 mpg all highway. My gauge reads dead on with the hand calculations, like less than a tenth off.

Thanks,

cwh

Some trucks stock are having surging issues. Do you have the latest updates from Ford?

[cwharding]

Yeah, I had the latest flash in December I believe.

[DavidPhillips]

You add what?

Hurry up and sell it and buy another one before it is completely toasted!

You don't use motor oil in diesel fuel.

[cwharding]

Originally Posted by DavidPhillips

You add what?

Hurry up and sell it and buy another one before it is completely toasted!

You don't use motor oil in diesel fuel.

One of the local refineries was doing some research on additives when they were getting reading to start producing the new ultra low sulfur diesel. The most effective additive that they found for use with the ultra low sulfur diesel was off the shelf 30W non-detergent motor oil. I've ran it in all my diesel trucks and have never had an issue. All of the diesel guys I work with also run it and have never had an injector or pump issue. It works well and is real cheap at walmart.

[DavidPhillips]

Please read this and then do your own research.

This has been a popular misconception for years. That's why they even put it in the owners manual not to use motor oil in your diesel fuel. They did not say don't put battery acid in your diesel fuel because nobody would do it. However in the case of motor oil people have been doing it. This does not make it right. Another thing people do is add ATF. This is also not good. All you want in there is ULSD.

You are changing the viscosity of the diesel fuel. The fuel delivery system is designed for ultra low sulphur diesel fuel.

You are adding something that is not meant to burn up in a combustion engine to your diesel fuel. This means you are adding more particulate to the exhaust systems of your truck. Simply using the wrong oil in the crankcase will result in too much particulate matter for the exhaust systems. When it's actually added to the fuel it results in much higher levels.

Motor oil is not formulated to mix with your fuel. 2 cycle oil is designed to burn and mix well. Lower grade 2 cycle oil has been found to not mix well with fuel and therefore tcw3 is specified for 2 cycle engines that demand high quality. This is actually for gasoline but tcw3 will also mix well with diesel.

An acceptable ratio is normally 128 to 1. However this exhaust system does not need to have any unburned oil go through it. It sounds like you are adding a qt (32 oz) to a tank so if your adding 32 gallons of fuel then your about there but these figures are for 2 cycle oil in gas not motor oil in diesel and not necessarily good in these new trucks. I would not use 2 cycle oil in mine either. 2 cycle oil was designed for a 2 cycle and not for the high heat we have in our engines. Motor oil is way worse than any 2 cycle oil in that respect. A 2 cycle engine will be toasted almost immediately with your off the shelf oil.

What is in your fuel also makes it's way into your crankcase. This means you are also contaminating your engine oil.


You are adding a lower btu substance to the fuel. This means your lowering the cetane rating. Not what you want for your truck.


With all the negative things why would anyone do it? Well it's because they were given bad information and believed it.

There is absolutely zero positive reasons for using oil in the fuel. The engine was designed to run on ULSD and therefore needs nothing else. If you insist on using lubrication there are products made for that purpose that are ULSD compatible.


"Nobody has had a problem" is not something that should even be considered as a valid point.

This thread was started because of a problem with the way a motor runs that's using oil in the diesel.

[cwharding]

Interesting point and a good read. Thanks for your input.

[08stroker250]

could be why your truck is ideling rough....