I have a 2002 F550 with a 7.3L diesel. Recently the dashboard emissions warning light came on and I experienced significant power loss at the same time. I checked to make sure the fuel caps on both fuel tanks were tight. I checked the fuel filter and drained some fuel off it to make sure there is no water in the fuel (there wasn't). I added some cetane booster to both fuel tanks, and drove about 30 miles. No improvement. I added an injector cleaner to the fuel tank and drove over 100 miles. No improvement. I checked the air filter and it appears to be okay. It was just changed 3000 miles ago. This may be entirely unrelated but we noticed a momentary smell like burning rubber several times in the past month. The smell disappears in a few seconds and I have not been able to find a possible source. Does anyone have any suggestions on the power loss and emissions warning light?

 

Would suggest reading any fault codes to give you a better idea on what is going on.. A code reader is a nice tool to own with these powerstokes, if you don't own one.

Welcome to the Forum...

 

I am not familiar with the emission warning light. How many miles are on your truck? With the limited info we have, I would check all of my intake system boot clamps. The most important are the CAC ones from the turbo to intercooler to the intake manifold system. 4 blue and 2 orange ones. May just have a boost leak. I suppose you don't have gauges or you would have posted about a lack of boost. Also, check the MAP sensor line from start to end looking for any leak that would keep the PCM from seeing the boost properly and putting the fuel to it.

The other required item to make power is fuel. Even though it is present in the bowl, there may not be enough pressure. Lotta things here, clogged filter, failing pump, clog in pickup system from tank.

Then there are other things like wastegate malfunction but I would get a code scan before I went too far.