New spark plugs - lower mileage ? - Toyota Nation Forum : Toyota Car and Truck Forums

cam01speak · 12-02-2006, 01:50 PM

i changed spark plugs on my 2001 camry 5s-fe last month. got OEM ngk laser platinums and ngk wireset. somehow i noticed that i am not getting the mileage my factory installed used to give. did any of you had similar experiences? is there a solution to this?

ToyotaToday · 12-03-2006, 02:22 PM

Quote:

Originally Posted by cam01speak

i changed spark plugs on my 2001 camry 5s-fe last month. got OEM ngk laser platinums and ngk wireset. somehow i noticed that i am not getting the mileage my factory installed used to give. did any of you had similar experiences? is there a solution to this?

Measure the resistance of your old wireset vs your new wireset. Which one has the correct resistance?

Mike Gerber · 12-03-2006, 04:38 PM

Just a thought. Are you comparing the fuel mileage you are getting this time of the year to fuel mileage measured during the Summer months? The colder the ambient air temperature, the lower the fuel mileage will be.

Mike

cam01speak · 12-03-2006, 05:07 PM

What is the correct resistance of the spark plug wire set and how do you measure it (multimeter?) ?

Winter temperatures : i didn't think about that. definitely a factor.

cam01speak · 12-03-2006, 06:15 PM

I measured the resistance of my old and new wires. I measured the longest and the shortest. The old one (long) where it said like 10.9 (in 20K setting), the new one is 5.9. The shortest was 5.9 (old) vs. 2.9 (new). I am thinking since the resistivity of the new one is lower than original, that should help, isn't? any thoughts??

DFBonnett · 12-03-2006, 06:36 PM

Correct.
I'm of the opinion that most of your situation is related to the weather getting colder, especially if you do a lot of short trips.

***toyomoho*** · 12-04-2006, 12:06 AM

I thought Toyota stated the max ohm reading was 25K per wire. Do you still have your old plugs? If so, might swap the old parts back in, then see if your mileage changes. What kind of drop in MPG are we talking about?

ToyotaToday · 12-04-2006, 12:38 PM

Someone mentioned that readings may vary in the winter and that is a good point. Make sure you take an average before drawing any conclusions the MPG is dropping. In other words, take several readings over a period of a month or so, then you would get a better idea what your average MPG.