Exhaust brake

[darrellr]

There probably is some effect on mileage but would be minor. Never bought this thing for economy . However I do keep track of my economy as it can be an indicator of engine health.

Why would there be a measurable effect on mileage? Just because the engine revs are up doesn't mean it is pumping fuel into the cylinders. I am not arguing, just trying to understand the why here.

 

[AH64ID]

Why would there be a measurable effect on mileage? Just because the engine revs are up doesn't mean it is pumping fuel into the cylinders. I am not arguing, just trying to understand the why here.

Becuase your coasting distance is shorter, so you use more fuel from start to stop. Some driving styles will see a decrease in economy and some won't see a change.

There is always zero fuel being injected during exhaust brake use.

 

[darrellr]

Becuase your coasting distance is shorter, so you use more fuel from start to stop. Some driving styles will see a decrease in economy and some won't see a change.

There is always zero fuel being injected during exhaust brake use.

I would be interested to see how much fuel difference there would be across a day, month, year of driving. It might be measurable, but I bet it won't be much. I get the logic here.

 

[AH64ID]

All depends on driving cycles. If you drive 40 miles to work with one stop sign you won’t see much. If you drive 10 miles to work on rural road with 5 stop signs then you’ll probably be able to see a difference if you coast as much as possible vs EB.

 

[darrellr]

All depends on driving cycles. If you drive 40 miles to work with one stop sign you won’t see much. If you drive 10 miles to work on rural road with 5 stop signs then you’ll probably be able to see a difference if you coast as much as possible vs EB.

Data will solve this. Lots of folks on here have alfa or other obd2 devices - maybe someone can run through 5 stops signs in a controlled nature using EB vs coasting and figure out what the difference in fuel usage reported is over that short period. This is another case of severely overthinking stuff that interferes with the enjoyment of life for me lol. But I do love data.

 

[Chaosh1]

So with obd jscan I can set it to be automaticly on? Did I understand the right?

 

[darrellr]

So with obd jscan I can set it to be automaticly on? Did I understand the right?

Maybe, but that is not the point I was making. It was more about the ability to monitor the fuel consumption over a short time. Having not used one on my Ram yet, I don't know if those pids are available like they are on my jeep.

 

[AH64ID]

So with obd jscan I can set it to be automaticly on? Did I understand the right?

No, remembered state is in the ECM which can’t be programmed with AlfaOBD or JScan.