CNG Accord
 

My relationship with the Honda Accord began back in 2002 when I bought my first one for $1,500. After puting more than a combined 750,000 nearly trouble free miles on three different Accords since then, I decided to experiment with Compressed Natural Gas. Yesterday I found an 05 Accord EX with a sequential injection CNG conversion already installed. At $1.50 per gas-gallon equivalent, I had to pick it up and try it out. If all goes well I should save nearly $3,000 per year in operating costs.
I'm certain I will have questions about the system as I get familiar with it, but I'm wondering if anyone else has experience with an Accord CNG conversion. Any insights to share? I'm pretty excited about this and looking forward to seeing it in action. I'm keeping my dependable 03 for awhile...just in case, but I've read and heard many great stories from satisfied CNG users. I'm hoping I can be one, too.

CNG conversion is pretty popular elsewhere in the world, where gasoline is $8 or $14 per gallon. It's been done in USA but not as popular as it is in UK or Europe.

If i remember correctly a byproduct the hydrogen sulfide can be corrosive to the engine and fuel system. So make sure you have the system checked thoroughly.

Natural gas is scrubbed of H2S. What would be the source?

Problem w/ CNG is availability of refill stations and expense of personal refill station ($5K-$10K retail).

Does this retrofit work in closed loop w/ O2 sensors or only open loop operation?

I think US could benefit from use of CNG, but extensive amount of expensive infrastructure for refueling is the problem.

good luck

There are several CNG fill stations near my house, and since it is a bi-fuel system, I don't have to worry about range anxiety.
Although the sytem is capable of working close loop w/02 sensors, the intaller opted not to hook up the O2 sensor cables; it relies solely on a mapping procedure to copy how the engine responds to idle, load, and cruise in various driving conditions and then reads the gasoline injector pulse times to deliver appropriate amounts of CNG to each cylinder. The installer did a terrible job with the conversion and I have made several changes to the mapping and hardware configuration with great results. The best result being that I am saving about 61% per week in fuel cost (about $120) with no significant loss in performance, maybe a little slower acceleration, but I have outgrown my urge to be the first off the line and now I focus more on the bottom line.

Last time I checked Houston had 2 CNG refill stations and none were helpful to my location. Personal refill looks to be too expensive w/ several years of payout to recover initial costs.

good luck

I've just had a sequential CNG system installed on my '03 accord coupe I4, two days ago. It seems to run fine except for the engine light coming on. Any ideas what could be the cause, and how serious it might be?

Ask the installer! I would suspect the injectors are disabled. This would likely cause a DTC to be set. Most kits claim to have an "emulator" to fool the ECU and prevent codes.

good luck

Certainly have someone read the DTC and tell you the actual code number (like P1234 or something like that). Not just some verbal description, get the number.

I am looking for an older cng accord from a private owner with maintenance records.
I will answer any replies, and would like input from any experienced owners.
Located in Central Arkansas.