After 76,000 miles, my wife said she heard a scraping noise coming from the underside of our 06 Civic Hybrid. I looked and sure enough, the plastic panel beneath the engine was hanging down. I went ahead and removed the remaining clips and 10mm bolts and took off the large plastic panel, exposing the engine, transmission, etc...

My question is, is this panel really necessary? I realize that the 'standard' Civic doesn't have the panels and it probably is only there to help mileage? Does it also help protect the electrical bits? We will probably try to keep the car for 3-5 more years so I wouldn't want to do anything to endanger the electric motor, but it isn't exactly a spring chicken any more either. The panel is pretty beat up so it would likely need to be replaced. I can't imagine it helps mileage that much, although with the front panel missing, will the remaining panels 'catch' the wind - should I remove the rest?

 

My 2007 had that panel taped on and it started dragging so I took it off and drove 1000 miles without it, but I replaced it with a new one when I changed the CVT fluid.

It does make the mileage a little better - I lost about 2mpg on the highway - no difference in the city.

If you drive mostly 45 mph or slower it can be left off, I believe that the Canadian civic hybrid does not have the under engine shield. So it is probably not needed except for interstate driving.

 

Hmmm... don't Canadians drive over 45 MPH?

 

2 mpg highway? Seems like if the difference was that much, every car would have them, given that they can't cost more than a few dollars for automakers to manuf. No offense, but I have trouble believing the difference would be that much without it.

My wife's commute is about 55 miles, with 30 or so on the interstate, and the remaining 25 going at slower speeds.

 

I could easily believe 2 MPG highway gain from a simple shield. Wind resistance and hills are the 'Top Two' arch-enemies of hybrid cars. You might find and compare fuel economy studies of drivers who cause added wind resistance by rolling their car windows down.

 

O.K. Steve, spoken like a person from a warmer climate, run your car in 10 degree temps, you will quickly find the #1 arch enemy of Hybrid cars is COLD, then wind resistance and hills

 

Nick, the only thing missing from your car is likely one or two of the clips. Do you get your oil changed by a third party: the dealer, or? Very likely they broke or lost a clip (or two, or three) and and said screw it. A replacement clip is $2~4. I would pick up what you need, plus a spare or two, and get the panel back in place.

Your car still is a spring chicken. I would definitely restore the underbody panels: they will improve your highway mileage, and keep the engine compartment clean, and even offer a slight bit of protection.

FYI, the Canadian model comes with all under panels, in some instances, and in other instances (the majority case I believe) it is missing 2 long narrow panels that run down the right and left midriff of the underbody.

Our car was in the latter category. I lobbied Honda Canada to supply me with those missing panels. They declined, claiming the right to change components and accessories region-by-region.

I bought and installed the missing panels myself. My full retail price was $64.71 (per panel) Canadian plus taxes. I also purchased sufficient clips for the new panels, only to find it came with clips. No matter, I now have lots of spares. Here's my thread on the subject:

http://www.cleanmpg.com/forums/showthread.php?t=18774

The only value to leaving the engine compartment under panel off is it will make access for engine oil and transmission fluid changes much easier, but all-in-all I would keep it on, for the aerodynamic improvement.

 

Hahahahaha. You think San Diego is warm??? It got down nearly to 50 degrees last night... brrrrrr!

(Nevertheless, I concede the point.)

 

Mendel, one other possible benefit might be to retain engine warmth which allows improved fuel economy... similar to a radiator blocker on the original insight. Agreed, i would definitely put them back on. Those Honda engineers are some pretty smart cookies!

 

My original shield was completly torn up. they (whoever owned it before me) duct taped the hinge area to make it one piece but that failed and the 2 clips left holding the front part gave up holding the shield on the interstate ( winds were realy strong and I think that is what caused the failure. ) all the holding holes had ripped from the plastic so I could not get it back on.

I tool off the remaining half and that did better than half with the front part missing.

I order the replacement and 8 of the push clips that hold it on from one of the mail-order Honda parts places. It was 40% cheaper than the local dealer want for the part.