Significant decrease in MPG - root cause?
#21
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^^^
No. Actually you should do that, but it does factor into total average mpg. I have always let my car warm up. My basic rule of thumb is not to let the oil pressure get over 90psi in the morning and let it idle for about 5 min. or more before driving. I actually use the oil pressure guage as my tach.
No. Actually you should do that, but it does factor into total average mpg. I have always let my car warm up. My basic rule of thumb is not to let the oil pressure get over 90psi in the morning and let it idle for about 5 min. or more before driving. I actually use the oil pressure guage as my tach.
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I thought it may be the weather! Glad you guys confirmed...
The car definitely doesn't like to start on cold mornings - my garage isn't heated. But hey, at least I have a garage, I suppose.
Still doing the preventive maintenance though as necessary... Thanks again guys.
The car definitely doesn't like to start on cold mornings - my garage isn't heated. But hey, at least I have a garage, I suppose.
Still doing the preventive maintenance though as necessary... Thanks again guys.
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Originally Posted by sno
Winter blend gas is the biggest problem, relating to overall mpg. I saw, at least, a 75 mile decrease in total miles for a full tank. That, and idling (or warming up) the car in the cold mornings burns gas without any mileage.
+1 I have been noticing that this past month. I have been going through my tank a lot more faster than ususal.
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I didn't notice a change in mpg with my Z when the temps dropped here in Western, NY but i took my Z off the road in November (wishes he was from PA, atleast they don't use materials on the road that lead to rust ie:salt).
#32
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Originally Posted by bailey bill
You will always get lower mileage in colder weather.
1) The ECU sets a richer A/F as temps drop
2) Winter blend gasolines also result in increased fuel usage.
bill
1) The ECU sets a richer A/F as temps drop
2) Winter blend gasolines also result in increased fuel usage.
bill
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Originally Posted by ZTMYDUST
(wishes he was from PA, atleast they don't use materials on the road that lead to rust ie:salt).
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On a side note, The digital gauge is actually pretty good (to my surprise). I calculated my MPG manually and it was within .1 of what the gauge said.
The speedometer on the other hand isn't as accurate. At low speeds like below 50 its almost dead on. Between 70-90 mph it reads between 2-3 mph high. Over 100 it's more than 4-5 mph high, and increases as you go faster. (All assuming that the GPS speedometer in my head unit is accurate)
The speedometer on the other hand isn't as accurate. At low speeds like below 50 its almost dead on. Between 70-90 mph it reads between 2-3 mph high. Over 100 it's more than 4-5 mph high, and increases as you go faster. (All assuming that the GPS speedometer in my head unit is accurate)
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