I have a 2005 / 6.0 PSD with about 95,000 miles on it. Even since it was new it has had an occasional issue when it is hot outside. It typically happens when I have been sitting at a stoplight idling. When I go to leave the light and accelerate it will make a lot of fan noise, and the power will stay flat until about 2200 rpms, then it will quiet down and the power returns and all is good.

It will also do the same thing in the heat when pulling a heavy load at a steady rpm and throttle position for a while and you then attempt to accelerate. I have dealt with the annoyance in the same manner for years and it is to just push the throttle to the floor, and it will clear up.

Over the years I have run no tuner, sct tuner, banks tuner, replaced the turbo, deleted the EGR and the one thing that has remained consistent is this issue. My theory is that the turbo is cavitating and that is the fan noise I hear, and the reason for the loss of power. I just don't know how to prove this, or change it. I look forward to your thoughts

Jon

 

The first question is do you have a moniter to watch live data? ECT,EOT , trans temp are some things that will make the engine fan come on. For example if one of these Sensers are malfunctioning it can cause the fan to come on. There is also the possibility of wire chafing . I'm sure some of the more versed members will chime in.

 

Thanks Edogsf350,

I do not have a data log system. I have had a mechanic run the codes on the engine once or twice, and there was nothing unexpected.

I do have the factory trans temp gauge, and that does not seem to waiver much after the truck reaches operating temp. The coolant temperature is not going up either, at least not enough to make the gauge change. The cooling fan is driven by a fan clutch, so there is no wire chafing causing the fan to come on. Keep the ideas coming because I am at a loss.

Jon

 

To go any further, we would require you to purchase a Scan Gauge II or something that will read the instruments that send info to the computer to turn your fan on. Drop about 150-60 clams into purchasing one. Your factory gauges are nothing but glorified idiot lights. Most all Auto Zones carry them. They are programable and could easily switch to a new vehicle.

 

The fan clutch is controlled by the PCM (engines computer). It reacts to various sensors and will speed up and slow down as necessary. The wires are in the plug on the top drivers side of the fan shroud. In addition to the fan speeding up, part of the cool down strategy of the PCM is to limit fuel (and power) until it cools a bit. It sound to me like that's what's happening. If the truck has done this for years and hasn't sprayed coolant out of the overflow tank or tailpipe yet, I would guess it's not really overheating. The PCM looks at several of the sensors but I would guess the oil temp sensor is reading too high and needs to be replaced.
This is a guess, if you were to do it right you would need to do a test drive with some sort of diagnostic equipment and verify the oil temp is registering high and the sensor is in error.

If you have an iPhone or Droid there are some options for pretty inexpensive engine monitoring. The ScanGaugeII is available at Autozone and goes for about $160. Highly recommended to have SOMETHING to monitor your truck with.

 

Awesome info!

I had no idea the fan clutch had any thing more than viscous fluid in it. I'm going to look into the scan gauge ASAP.

Thank you!

Jon

 

Ok, I went and picked up the Scan Gauge II at Auto Zone for $159, got home to install and realized that I would need to disconnect my Banks 6 gun in order to plug this device into my OBD II port.

I found a "Y" cable for the OBD II for $25.00 at OBD diagnostics that looks like it would work so that I could use both devices at the same time. Has anyone done this?

Thanks again!

Jon

 

The Y cable is hit or miss depending on the devices you're trying to use. I don't think the cables are expensive it may be worth a shot but don't be surprised if they don't play well together.

 

You'll need to enter the XGauge codes for the EOT and some of the more useful gauges. Here's a video that may shorten the learning curve:

Entering codes on SGII

And these are the codes for Engine Oil Temp

Engine Oil Temp.
07E0221310
046245130610
3010
00090005F05F
EOT

Many more are available.

 

Thanks Rusty Axlerod,

I Installed the scan gauge 2 and drove the truck for a couple of days and it did not have the issue during that time. EOT was hovering about 210 and the water was staying 190. Since then I have been out of town, and my truck at the airport park and ride, so I've not tried out the Y cable or been able to duplicate the problem while watching. I'm sure summer is not over in Texas, so I will get another chance soon!

Jon

 

Verify in the AM before you crank that both the ECT/EOT/TFT are within a couple of degrees of each other (and should be about outside temp).

Assuming codes were entered properly that 20 degree delta is a sign of a clogged oil cooler - if your EOT gets too high the FAN WILL turn on.

Your origin scenario - stopped at a light - is EXACTLY when your oil temp would spike since less air is flowing over the engine at idle when not moving.

The SG2 is a "must have" for a 6L owner - good luck..