tedo

... 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?

Jedi54

iTrader: (7)

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?

tedo

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?

fyrstormer

I've discovered that the thermometer, when set to Celsius, is a good indicator of expected gas mileage. 13.5 is pretty normal for this car in this weather.

tedo

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

tedo

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

tedo

*Update* Engine's on its way! Will be here in 3-4 weeks! =D

This is good news to all trying to get engine replacements; I got it with only 1 oil change receipt.

terch1

iTrader: (2)

Hot start issues are more times than not directly related to poor compression. Schedule yourself an appointment at your local dealer.

tedo

??.. I already did -- a new engine's on its way. Did my previous posts not show up?

terch1

iTrader: (2)

My bad! See I was right. lol.