Check Engine Light
 

At 6,000 miles the check engine (elevated exhaust, etc) light came on on my diesel X5 while on a trip. There is no misfire and the engine is running fine. I drover the car back home, a 250 mile trip without any problems. I checked the fuel cap and it is tight. There are no check codes being generated by this warning light. The dealer will get the car tomorrow and seemed concerned as they had not had any experience with the diesel and this issue. I will post again when the dealer looks at the car. Any other thoughts or suggestions would be welcome in the meantime.

Got car back last Thursday (04/02) with diagnosis of moisture in fuel. Tech said he did not know why this was triggered and there was no way to test as they do not have a method to test for water in diesel fuel. Said car was running fine. Left next day on 250 mile trip with no problems whatsoever. The next day after I filled up with diesel to return home, warning light came on 30 minutes later. I am purchasing diesel at the same places I did for the first 6,000 miles of the car. Anyone know of a test for water in diesel and what might be triggering this warning?

> diagnosis of moisture in fuel. Tech said he did not know why this was triggered and there was no way to test


LOL!


And how does one diagnose the problem as moisture in the fuel, if one cannot test the fuel for moisture?


They should hire some real mechanics at your dealership. It sound like the "moisture in the fuel" is the catch-all reason when they can't figure it out and just hope it goes away.


Sorry to be so harsh, but having seen mechanics do this to people many times in the past (when I worked as a mechanic), it ticks me off.

FWIW, Blackstone labs can test a sample of your diesel fuel and tell you how much moisture is in it:

Blackstone Laboratories


I do not know what they would charge, but in response to an e-mail I sent them they replied, "Yes, we can tell you if and how much moisture is present in your diesel fuel."


I'm sure if you dropped them an e-mail, they could give a price and directions on sampling the fuel.

You should get your fuel where they sell a lot of diesel fuel. I get mine at a busy station where they have a lot of turn over on their diesel. Go to a truck stop, or find out where they sell a lot of diesel fuel and purchase your fuel at a different station...

Craig