The forgotten HX - Story of an '01 Civic

[darcane]

Lean burn.

The best thing since sliced bread and everyone wants it. You have your 5th gen Civic VX, 6th gen Civic HX, and your 1st gen Insight and then it was eliminated for emissions (?) reasons.

But wait, there's more! From 2001-2005 they continued making the HX. It has a 117hp 1.7L VTEC-E engine with lean burn. .gov currently rates it at 31/39mpg. And here is the one I own:


I bought it this summer and first fixed a bunch of the problems that made it quite cheap (like replacing the pass. door that the original owner's angry ex-boyfriend scribbled "B*tch" in). Started commuting in it and was getting 40mpg in warm summer temps and light traffic.

First mod, a grill block:


This is blocking too much air for summer, but I am leaving it during the winter months.

[darcane]

Next step: remove that spoiler. I have no conclusive proof that it helps or hurts, but I really don't like it. I posted an ad on CL to swap and found a kid that wanted my trunk lid. So, we swapped:


I also removed my squeaky power steering belt at this time and didn't bother replacing it.

[darcane]

Next step: air dam.

I saw on a Miata forum, that someone had used paver edging to build an air dam. It was about the right depth and is nice and rigid. I also looked at a garage door seal that is popular for doing the same thing, but I'm pretty sure it would deflect which would defeat the purpose.

I pulled off my bumper last night and got to work. Here you can see it attached, as well as an unmodified piece of the edging.

There is also a new upper grill ($20 shipped off eBay) with a coroplast grill block. It's a very poor fit, but it will do. This is also new tonight. The edging is held in place with 1/4-20 screws/nuts with fender washers. Since it is so rigid, this only works because the bottom of the bumper is flat.

There is also a lot of damage to the underside of the bumper, and this helps reconnect a lot of the pieces and stiffen it all up.

And here it is on the car:




Not bad for $30 total.

[ChazInMT]

My only concern is that you've gone too far on blocking off the air. A $1,000 to $3,500 repair bill does not offset the .5mpg you might be saving by letting in a bit more air down low.

Another "Hot" tip, form a guy who's been there, Change Your Thermostat!!! Cheap and easy to do, crazy easy, and it could save you the $1,000 to $3,500 repair bill if it overheats. Mine went out on me in Atlanta last spring and made a leak in my head gasket which is almost certain to happen when it over heats. It was due for a new timing belt anyway so I combined the 2 repairs and got away for $1,200. But in the back of my mind I always wonder if a screw wasn't tightened just right and I'm left walkin.

But I digress.....

Excellent job otherwise in all respects on you great HX!!

[Daox]

Yeah, just keep an eye on the coolant temp and make sure the e-fan isn't running too much.

The mods look good!

[darcane]

Originally Posted by Daox

Yeah, just keep an eye on the coolant temp and make sure the e-fan isn't running too much.

The mods look good!

Yes, that is a concern, but the Ultragauge is keeping tabs on my temps. On my commute in this morning, it never got over 195°F but it's about 40°F outside. I'll open up the lower block when it gets closer to summer and temps warm up.

In spite of the cold temps and heavy rain/standing water, for the highway leg of my commute: 59.6mpg.


I won't be able to keep it up that high though, I reset after the car was mostly warmed up and I had driven through the portion of my commute with more stoplights and traffic.

[ksa8907]

Curious how you can tell if it has lean burn. My dad has an '01 sitting around with a bad rod bearing that he's too busy to fix. It has the 1.7, but im not sure of its vtec. 5spd

[darcane]

Originally Posted by ksa8907

Curious how you can tell if it has lean burn. My dad has an '01 sitting around with a bad rod bearing that he's too busy to fix. It has the 1.7, but im not sure of its vtec. 5spd

Well, all the US market Civics in '01 had one of three 1.7L engines. The DX and LX have a non-VTEC engine. The EX has VTEC, and the HX has VTEC-E (E for economy). The trim level should be displayed on the rear of the car, but the emblem could have been removed.

The HX was only a coupe, so if you have a sedan, it's not an HX. The O2 sensor in the exhaust manifld should have 5 wires.

You could also run the VIN through this to determine if it is an HX:
Home : Free VIN Decoder - Vehicle Identification Number Check

[MetroMPG]

Originally Posted by darcane

and then it was eliminated for emissions (?) reasons.

That's a good question, about why they don't offer lean burn anymore.

The 5-speed Insight had an ULEV rating, even with lean burn: ULEV = "emits 50% less polluting emissions than the average for new cars released in that model year."

So I have to wonder if it was eliminated more for driveability/consumer acceptance reasons.

Originally Posted by darcane

Next step: remove that spoiler. I have no conclusive proof that it helps or hurts

I think you made the right decision - that style is more likely to hurt MPG.

For comparison, Honda did put this drag-reducing spoiler on its 2001 Civic sedan. Most OEM drag-reducing spoilers on high-MPG cars are flush mounted, and fairly subtle, like this one is:

[darcane]

Originally Posted by MetroMPG

That's a good question, about why they don't offer lean burn anymore.

The 5-speed Insight had an ULEV rating, even with lean burn: ULEV = "emits 50% less polluting emissions than the average for new cars released in that model year."

So I have to wonder if it was eliminated more for driveability/consumer acceptance reasons.

I assume the ULEV rating is during standardized tests that may not hit the very specific requirements to engage lean burn. I haven't seen any testing, but I have to assume NOx emissions are high when it's engaged and this a likely reason it was killed.

However, these are only assumptions.

Originally Posted by MetroMPG

I think you made the right decision - that style is more likely to hurt MPG.

For comparison, Honda did put this drag-reducing spoiler on its 2001 Civic sedan. Most OEM drag-reducing spoilers on high-MPG cars are flush mounted, and fairly subtle, like this one is:

Subtle indeed. I don't think I've ever noticed one on an actual car.

I figure there is a chance that the spoiler could be near the right height to reattach airflow, but I doubt it. No chance for any thorough testing, but I won't miss it either way. It was kinda ugly, and I much prefer the clean look it has now.

Upcoming plans: lowering it an inch or so and full moon discs.