I recently replaced my 2004 HCH I's battery pack and 12v battery (see https://www.greenhybrid.com/forums/f...-repair-30543/) and am now looking for tips on prolonging both the life of the pack as well as of the car itself.

The car only has 68k miles, I hardly drive it...sometimes it sits for a few weeks untouched, which I'm told is one reason why the pack likely failed. I'm not up to the task of grid charging, rather I plan on simply driving it more often. I live in Denver (very hot summers, cooler winters) but don't often take it in to the mountains, my driving is mainly city, short trips. Would longer city trips say once a week be sufficient to keep the pack happy or should I really give it the business regularly by taking it up and down mountain roads? Should I have the windows tinted or always park it in the shade in the summer or is that overkill?

Apart from the IMA system, what other maintenance tips would you recommend? Meaning, beyond what it covered in the maintenance schedule in the owner's manual? Are there parts/sensors on this model that typically fail sooner than expected or from sitting?

I've never flushed the brake or (manual) transmission fluid so I plan on having them flushed during the next oil change. Would you bother with replacing plugs/coils, the drive belt, or even timing chain this soon?

As I recently invested about $2600 to keep this beast alive I'm looking to give it the best chance to give me another 70k or more of use, thanks!

 

I agree that extended sitting likely contributed to the failure of your battery.

Follow any recommendations given by the battery supplier. Additionally, ask if grid charging is recommended, or if it voids the warranty. If it doesn't void the warranty, I recommend you conduct a 24 hour grid charge at every oil change. Driving is NOT a substitute for grid charging. Normal operation produces cell imbalance due to limitations of the design. HOWEVER, regular driving is needed to keep the pack within an operational range and prevent excessive imbalance due to excessive self discharge.

I recommend you drive at least 3-4 days a week for 10-15 minutes AT operating temp with full IMA function observed (normal assist/regen). IF you let it sit for > 1 week, I recommend you disconnect the 12V battery for 30 seconds, reconnect, start and idle car. If it will charge at idle, allow it to idle until full SoC. If it stops charging, rev to between 3500 and 4000 rpm and hold until full SoC.

Since you don't know the status of the fluids, I'd do them all within a reasonable timeframe.

Plugs are replaced at 100K, but given the age, you might want to do it. Replace with ONLY the Denso or NGK spec plugs. They are expensive, but you should be able to get them from a part store for $14-15 each. There are 8. On in front and back on each cylinder.

Replace coils only if you think you have an ignition problem. I had to replace one because there was a slight stumble. Fortunately, with a second car, I had lotsa spares for testing. There are 8, and a Hitachi aftermarket option can be had for about $45 from Rockauto.com. Given their cost, I would only replace as needed

Limit heat as much as possible. Window tint is a good idea. CO isn't an extreme from a heat perspective, but interiors can get hot as hell in direct sunlight. Park in shade or park with a front window shade installed, and orient the car in such a way as the window shade will block the most sun for the longest period of time. Leave the rear windows cracked. Start driving with windows down and A/C off going very easy on the assist/regen until the interior air has equalized with outside. Use A/C as needed using the highest set temp you can tolerate for mileage considerations. Aim the center vents to direct air up and straight pack to the rear deck as the IMA fan inlet is the vent at the front of the rear deck.

Drive it like a hybrid. Keep normal accels to 1600-2000rpm and freeway type accels to 3000rpm where possible. Watch traffic and signals ahead to anticipate and avoid stops or unnecessary regen/braking. The less you use the battery, the better mileage and battery life you will get.