Low MPG and a little "hot-start" problem..
Low MPG and a little "hot-start" problem..
... what could it be??
After doing research around here, my best guess is low compression, but before I take it to the dealer for a test I thought I should ask you guys first.
Here's some more details about the car:
05 Shinka 6speed mt
69k miles
Plugs, wires and coils were just replaced about a month ago
Averaging 13.5mpg (my last two fill-ups were 14 and 13, 70% city driving)
The car still starts when warm.. but takes about 3-4 sec more of cranks than when cold
Any other theories or suggestions of what to do next?
After doing research around here, my best guess is low compression, but before I take it to the dealer for a test I thought I should ask you guys first.
Here's some more details about the car:
05 Shinka 6speed mt
69k miles
Plugs, wires and coils were just replaced about a month ago
Averaging 13.5mpg (my last two fill-ups were 14 and 13, 70% city driving)

The car still starts when warm.. but takes about 3-4 sec more of cranks than when cold
Any other theories or suggestions of what to do next?
the mpg isn't always a great indicator as it can change quite a bit based on your driving style.
Could it be a starter issue?
still running an OEM catalytic converter?
any other symptoms?
Could it be a starter issue?
still running an OEM catalytic converter?
any other symptoms?
The starter and catalytic converter haven't been changed. I'm probably wrong here, but if the starter is the problem, wouldn't the hard-start happen both when the engine is cold and hot?
No other symptoms that I know of; no loss of power (though not entirely sure, as I only had the car for 2 months). Anything in particular that I should be looking out for/pay special attention to?
No other symptoms that I know of; no loss of power (though not entirely sure, as I only had the car for 2 months). Anything in particular that I should be looking out for/pay special attention to?
The weather is getting cold where I'm at (Pittsburgh, PA), but even so I've never got 15 mpg or more even when the weather was still warm; it's been consistently 13-14.
According to fuelly.com that's way below average... but is it? If its normal then I wouldn't need to worry so much
According to fuelly.com that's way below average... but is it? If its normal then I wouldn't need to worry so much
So I just got back from a compression test at a dealer, results they gave me are:
Rotor 1:
5.1
5.0
5.0
Rotor 2:
4.9
4.8
4.9
@182rpm
Running the numbers through the calculator gives me about 6.7 and 6.5 avg @250rpm, both under Mazda's min spec for rotary engines (6.9).
I got my car back and they are filing the request to Mazda NA and will call me whether I am getting a new engine or not. The only thing that worries me is that since I only got the car ~2 months ago I only have 1 oil change receipt. Hope it goes through anyways
Rotor 1:
5.1
5.0
5.0
Rotor 2:
4.9
4.8
4.9
@182rpm
Running the numbers through the calculator gives me about 6.7 and 6.5 avg @250rpm, both under Mazda's min spec for rotary engines (6.9).
I got my car back and they are filing the request to Mazda NA and will call me whether I am getting a new engine or not. The only thing that worries me is that since I only got the car ~2 months ago I only have 1 oil change receipt. Hope it goes through anyways
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