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Ask Dominick Your Own Question
Dominick, Marine Mechanic
Category: Boat
Satisfied Customers: 1009
Experience:  25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified
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I have two D6 300 engines on my boat and they both have been

Customer Question

I have two D6 300 engines on my boat and they both have been running well. Now one will not get over 1500 rpm and is locked out from more rpm. We changed the fuel filters and all is good with fuel but still no power.
JA: Is the power loss consistent, or does it fluctuate?
Customer: consistent
JA: What year is your 1500?
Customer: 2007
JA: Are you fixing your 1500 yourself? What have you tried so far?
Customer: fuel filters - both changed - no issue with fuel now but we did find lots of stuff in the separator.
JA: Anything else you want the mechanic to know before I connect you?
Customer: I think the electronics have been locked out and need to be reset but I have no proof of this.
Submitted: 3 months ago.
Category: Boat
Expert:  Greg Robinson replied 3 months ago.


It sounds like the air temp sensor. It is located under the metal cover on starboard side. One torque screw mounts the sensor. You could take the known good one and temporarily install into other engine and test. Although it doesnt throw a code if you had a vodia tool you would see 300 degrees on the sensor.



Customer: replied 3 months ago.
thanks but I think it is the Boost Sensor that has failed.
Customer: replied 3 months ago.
I am ok now - thanks
Expert:  Greg Robinson replied 3 months ago.

What is a boost sensor?