Hi,
I noticed MPG drop after using 86 Octane gas from 91 Octane.

I just bought Bosch Platinum+4 (4417) plugs to try out and see whether it will increase MPG and Power.

BUT dealer told me not to use it. He said that would cause adverse effect on emission, and screw up the computer system. I also heard that these plugs causes the engine to run hot, and the plug tips get some stuff deposited. Any comments ? Please comment on what this plugs might damage, not whether it will increase MPG or not

I like to try, but worried about above issues and more unknown stuff happening. ???

Tx,
BG

Hi Bgsenevi:

___There is a lot of reasons for FE drops but regular unleaded isn’t one of them that I know of.

___The plugs? Insight plugs are indexed so that the electrode points a particular way. I don’t know if the HCH’s are but the OEM plugs are good for at least 105,000 miles IIRC. Don’t change them as they won’t help FE or performance in any way, shape, or form.

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___Waynegerdes@earthlink.net

Hi,
I put the Bosch plugs in and drove around 200miles so far. But that was to a 11,000ft mountain. So, I can't tell whether MPG went up or not.

Good news is that I did not notice engine running hot, emission or computer trouble. Seems to be running smooth so far. I will keep you updated with what I find.
Tx,
BG