Jonnys3

I've recently taken ownership of a WRX Hawkeye (previous car was a bugeye wagon). I've come to notice that if the car is stood for the weekend, it doesn't like to start immediately come Monday morning, and usually takes 2 or 3 attempts to fire up. It then continues to hesitate in this fashion for the next 3 or 4 times at starting and then returns to normal until it is stood unused for a couple of days again.

I was a bit concerned the first time it behaved like this, especially as it was the weekend after it had its major service - I was thinking allsorts: alternator, coolant temperature sensor or even a dodgy batch of fuel, to name but a few, but I've now observed it behaves in this manner whenever it has been stood for a couple of days and am beginning to accept this is the norm (although I never had any such issue with my bugeye wagon which could go for over a week without being started and still start first time).

After reading around, these symptopms would suggest I've got either a parasitic battery drain or a duff battery ?

My initial instinct was to go for a new battery first and rule this out since I don't really know how old the current battery is, but as I was looking at an Optima Redtop RTS 3.7 R on a website, a customer review caught my eye which suggests the 2.5 WRX 2007 has loads of additional 12v power drains?

I've noticed on mine the ignition barrel always lights up whenever I unlock the car, and that the power light on the factory fitted head unit flashes rapidly when the car is immobilised, so already that's two potential sources of additional key off drain which I didn't have on my bugeye. So my question really is this: is the Hawkeye well known for its key off battery drains ?

I've since held off purchasing a new battery as I don't want to shell out over £100 on a Redtop if it's not going to make things any better. I've tested the existing battery (albeit midweek when all is normal) and it measures at 12.5v with the engine turned off, and 14v when the engine is running (and the alternator in action ie sidelights on as well). This would suggest that the battery and alternator are both fine, although I cannot see what make or model the battery is so cannot confirm what the CCA/CA are - presumably these must be an important factor too (whilst the battery might report the correct readings of 12.5v & 14v, if it's not got suitable CCA/CA could this be an issue) ?

I'm not really sure what my next action is but I'm thinking my options are (in no particular order):

1. Purchase new Redtop battery
2. Purchase CTEK MXS5.0 Battery charger to perform a deep clean / charge of existing battery and use when the car is stood long enough to drain the battery
3. Assume all is well with existing battery and pursue the parasitic drain.

mickeymouse

Assuming you have no proof of purchase for a new battery.. Then the one you have is coming to the end of its life.. I changed the battery in my hawk about 18 months ago.. Mine just wouldn't start after not being used for a few days at first.. Then after a day or two.. Then just wouldn't hold a charge at all.. Iirc I got mine from a main dealer and was about £50 cheaper than halfords..

So a new battery would be my first job..