langglemd Report post Posted August 7, 2011 My 400 Cummins was running smooth. Stopped for diesel at a truck stop. Had a little more than 1/4 tank in my 100 gal tank. Put in approx 25 gal. After driving about twenty miles engine burped a couple times and then smoothed out. Few more miles, same thing and noticed check engine light came on. Pulled to side of road, check engine light went off and engine was running smoothly. Only had a few miles to campground so drove on and last 3 miles check engine light stayed on and engine was missing more frequently. Opened petcock on fuel filter and drained about an ounce of clear liquid, smelled like diesel but could have been water, not sure. Anyone experience this and have a possible solution if it is water? Rig is a 2005 HR Endeavor. Share this post Link to post Share on other sites
wolfe10 Report post Posted August 7, 2011 If you got a clear liquid from your primary fuel filter/water separator, that was water. Diesel is golden in color. This is easy to see if you have a clear plastic bowl fuel filter rather than one that is all metal. Any layering that you can see in the clear bowl is a sign of a problem. Best advice that doesn't cost a lot of money is to buy a couple of extra primary filter elements. Continue to stop every 20-25 miles to check/drain water. As long as the water level does not reach the filter element (i.e. is only in the bottom of the bowl) the filter element itself has not been compromised. Once the filter element gets wet, it needs to be changed. There are some alcohol-based products that absorb water, but you are better off just removing the water from the system as some of these additives are not particularly good for the injection system. If you will be storing the coach before getting to that 100% water-free status, then an additive may be a better answer. Brett Share this post Link to post Share on other sites
langglemd Report post Posted August 9, 2011 Thanks for the info Wolfe10. Had to have a mechanic look at it today and it appears there is a problem delivering fuel from the gas tank to the water separator filter. He put a gas line down the filler tube and attached it to the water separator filter, bypassing the original gas line, and it runs great. He seems to think the pickup tube in the gas tank has separated and is sucking air along with a little diesel. When he took off the water separator filter it was only about one-third full of diesel. He said it should be full. Will post the final results tomorrow. Don't mean to ramble on but this may help someone in the future. Share this post Link to post Share on other sites
wolfe10 Report post Posted August 9, 2011 Two possibilities: 1. Problem in the tank with the fuel pickup. 2. Problem in the fuel line from tank to primary fuel filter. A loose hose clamp or too tight a hose clamp that has cut into the fuel line and allows air in the system could also be the issue. Brett Share this post Link to post Share on other sites
langglemd Report post Posted August 16, 2011 Well, after 7.5 hours of diagnosis, it was determined that the problem was the cam position sensor, a $39.00 part. Good news though, when I bought the rig the previous owners transferred their extended warranty to me. Warranty picked up everything except the service call the day before and the $100.00 deductable. Share this post Link to post Share on other sites
kenosavvy Report post Posted October 5, 2011 What is a cam position sensor, what does it do and where on the engine is it located? Share this post Link to post Share on other sites
Luke39 Report post Posted November 30, 2011 My water in diesel fuel filter warning light has been coming on briefly for the last 20,000 miles. The guy I bought the car off told me it had been happening to him for ages as well. I personally wouldn't worry about it. Think of it as a nice little reminder that you own an Alfa and smile all the way to the airport. Share this post Link to post Share on other sites
Rexi1212 Report post Posted December 2, 2011 The information above provided is really valuable. Share this post Link to post Share on other sites
wolfe10 Report post Posted December 2, 2011 My water in diesel fuel filter warning light has been coming on briefly for the last 20,000 miles. The guy I bought the car off told me it had been happening to him for ages as well. I personally wouldn't worry about it. Think of it as a nice little reminder that you own an Alfa and smile all the way to the airport. Not sure suggesting one ignore a "water in fuel" warning light is sage advice! Brett Share this post Link to post Share on other sites
ckelly10 Report post Posted April 26, 2012 Thank you soooooooo much for this post...I had a simlar problem with the diesel fuel and water but when I took it to my local garage they couldnt find the problem. Was about to give up hope but luckly found this forum on google. Share this post Link to post Share on other sites
