Any of you notice a decrease in fuel mileage when you use a front cover and travel on the highway? I once noticed approximately a 2 mpg drop in my Civic on a 300 mile trip running between 70-80 mph. But I've never repeated the exact trip in that car to double check the results. On the same trip I recently only managed 25 mpg with my 03 Protege. I'm wondering, if in addition to the normal suspects - tire pressure, alignment, fluids, A/C on or off, temperature, driving style, etc. - if the cover contributed to the poor gas mileage. Any ideas?

 

I have the front mask on my 02 P5 90% of the time, so I could not say.
But highway mileage going 65-70 mph is 30 mpg. Going 55-60, it was as high as 34.5 mpg.
I had bike racks on the roof rack, and they definitely affected mpg, so off they came.


Denny

 

Thanks for the reply. We all know gas mileage is greatly affected by speed and drag. Your figures prove this point perfectly. Only I'm surprised at how much gas mileage is affected. I guess my question is, does the front mask cause that much drag? It fits flush on the bumper and only slightly raises the profile on the hood. Anyone with any thoughts or numbers?

 

Are all of your corners secured on the bra? I see so many cars driving down the road with one (or more) of their sides flapping. Also, does the bra cover any of your openings in the bumper? A lot of them have mesh screens to cover those openings and that would create a greater resitance to flow. Don't really know how much that would increase your drag though.

 

For the record: I run 40 psi in all four tires. I use Mobil 1 5W-30, Bosch Platinum+Four spark plugs and have a K&N air filter element.

Denny

 

isn't 40 psi, kinda too high for the tires,, wouldn't that start wearing out from the middle pretty fast and quite possible loose traction when cornering?

 

The stock tires will take over 50 psi max pressure. They are not wearing in the middle. In fact, they are wearing evenly straight across. I rotate front to back every 5k miles. Ride is a bit more firm. Have not had a problem with cornering traction. But I don't drive like a maniac either.

Denny

 

Wow! 40 psi is more than I thought was needed for the highway. But it obviously works for you, and I'm sure helps contribute to your gas mileage. I usually ad 2-3 psi over the recommended pressure if I'm taking a trip or heavily loaded. Just for the record, I had 34 psi all around and 10W30 (I suspect anyway, since I just bought the car from a dealer). My car has 5500 miles on it so I know the plugs and filter are good. And I have the OEM cover and made sure it wasn't loose or flapping at all. Otherwise, I bet this would definitely hurt gas mileage, like you suggested.

I took the car into Mazda today for a few incessant interior rattles (driver's B-pillar, rear deck, and dash) and startup clatter. I aksed them to check out the alignment too. I asked about the mileage and the servcice advisor said it was low average. He says he can run a test on the car to check the mileage, and that it involves a test drive of 10-12 miles. We'll see what he comes up with, hopefully tomorrow. If anyone's interested, I'll let you know. Thanks all.

 

Yes, please let us know. BTW, the 40 psi fiqure came from a tire/alignment shop owner of many, many years. Pretty sharp guy. He co-hosts a weekly car program on the radio here on the Central Coast of California.

Startup clatter? Can you describe?

Thanks
Denny

 

are you getting a bra for your car? if i were getting a bra, i would get the new clear ones out, its like thick tape, for lack of comparison.

 

Startup clatter - worst on cold mornings, say about 30F. Will also occur after car has sat for several hours, but will last only one second vs. 2-3 seconds on a cold morning. I can't describe it any better than clatter, like when you've just changed the oil and its noisey for a second before the oil pump primes, fills up the empty filter and begins circulating the oil. I found the TSB about the siwrl (or was it tumble) valves, so I'm wondering if that's it. I brought the TSB with me to the dealer today. Otherwise, it's probable just a cheap filter without an anti-drainback valve. I just bought the car and haven't switched to the OEM Mazda filter + Mobil 1 that I plan to use.

As for the clear bras - I know 3M has a product. I've seen it on several cars and it does look inconspicuous. You could walk by and not even notice. OTOH, I see a car regularly that has this clear bra on it, and it has yellowed noticeably. The car is never washed, so maybe that contributes. Or maybe it's an older design. Something to consider. It'd be great to hear some first-hand testimony on these.

 

I just went to clean my front mask, and after only one use one of the tabs is hanging on by two threads! I'm going to call the dealer I bought it from and see what they'll do. Too bad they're 300 miles away.

 

I also use K&N oil filters because they have a handy "hex head" on the bottom making for easier install and removal. But they cost more.

Denny

 

I bought an OE front mask (looks cool) for my 02 P5 shortly after I bought the car.

The weak spot are the two bottom straps. The Velcro straps break. A cheap, but effective fix is to cut the strap, add a two inch Velcro extender and reattach the cut strap to that extender.


Denny

 

Any one else have the clear protectant on their side skirts? I have it on my 2000 pro. I wash it regularly but the owner before me didn't, so it's got a very small amount of dirt stains but not really noticeable until you get down there close.