DIY Home Improvement Forum banner

Spark Plug recommendations

2K views 6 replies 3 participants last post by  mspiegle 
#1 ·
Another quick question.

I am going to replace the SP's and wires for my 2004 3.4L Impala.

I am looking for optimum gas mileage.

Any recommendations on plugs?

I see so many choices from reg plats to 2/4 headed plugs... any of the hype worth it?
 
#3 ·
I've had very good luck with the NGK Iridium plugs in a few different cars. I tried the Enerpulse Pulstar plugs (http://www.pulstar.com/), but am not convinced that they are worth the money. If you do try them, be aware that they are incredibly fragile and may break during installation.

If you're looking to improve your MPG, you can also look at your injectors, O2 sensor, air filter, and tire pressure. Keeping those items clean and in good working order will also help.
 
#4 ·
The air filter was just replaced to a K&N filter.

Tire pressure is always a good thing to watch I agree.

Mitchell software says that my ideal tire pressure is one thing, but then I have heard that filling tires to their max rated pressure is the best. Any opinions on that?

Also, arn't checking the injectors and O2 sensor rather difficult?
 
#5 · (Edited)
Your ideal tire pressure is based on the weight (and weight distribution) of your vehicle to provide the best balance of handling. This is the number you'll find in the door sticker, and probably in your Mitchell software.

I personally wouldn't fill my tires up to the max as it will result in poor tire wear. If I'm concerned about MPGs in my own vehicle, I will fill them up slightly over the manufacturer's recommended pressure, but still below the maximum rating for the tire.

Actually checking the O2 sensors/injectors is difficult, you are correct. Most O2 sensors last to about 60,000-75,000 miles. Some can make it as long as 100K miles. Problems such as running rich, misfires, and oil burning can significantly reduce the life of your O2 sensor. If your O2 sensor is tired, your car may not be running with an ideal fuel mixture. Depending on how dirty your injectors are, a bottle of techron could be beneficial. If your car passes smog tests with flying colors, then your O2 sensor is probably fine.

Edit: I just re-read that your car is an '04. You probably don't need to worry about your O2 sensor or injectors. Aside from proper tire pressure, your best tool for MPGs could be your own driving habits. For me, driving very conservatively saves 3 MPG.
 
#6 ·
The gas mileage seems to be pretty good, I get almost exactly 30mpgs highway on a 3.4L v6. Impalas arnt the lightest cars either, so I am not disappointed.

Speaking of cleaners, I have used Fuel Injector cleaners before and been very impressed. I cant remember the brand name, but they make a ton of stabilizers and treatment products. They always have those little gear demos at the car shops.

Would using a treatment like that be bad if the injectors are already clean? Or can they help maintain cleanliness?

PS - It would be cool if there were a web site that would give tire pressure estimates. Like one where you would tell it the car, and then describe who drives it the most and the seating distribution, and then have it tell you which tires at what pressure.
 
#7 ·
I think the cleaning product you're referring to is made by Lucas.

I don't think constant use of injector cleaner will help much. You shouldn't need to use it any more than once per year. As they say, if it ain't broke, don't fix it.

I imagine if you're looking to increase your MPGs, you're probably looking to save money where possible. You need to balance out the cost of these additives with what they will really do for you. Often times, it's very hard to gauge the actual benefit you'll receive.

There are a couple other areas where you could have guaranteed savings:

Fuel octane: If your car is rated for 87 octane (check your manual), you get no benefit out of using higher-octane gas.

Oil changes: Most people change their oil at 3K miles, but that may be too excessive for your vehicle. You can check your manual for guidelines (many vehicles have a change interval of 5,000 to 8,000), but the only way to be 100% certain is to send your oil in for an analysis (http://www.blackstone-labs.com/gas_engines.html). It isn't that expensive and could potentially save you lots of money in the long-run.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top