VX California to 49state Conversion help - Fuel Economy, Hypermiling, EcoModding News and Forum

oldertech · 03-22-2009, 01:12 AM

Hello,

Yep, another California Honda Civic Vx, 1995, trying to convert to enable Lean Burn. I acquired the proper computer, 5-wire sensor, and an engine loom from a 49state car. Hooked it all up and got a flashing CEL and clicking ignition relay under the dash. Never heard the fuel pump start up, and didn't attempt a start. Any thoughts?

Scott

NiHaoMike · 03-22-2009, 09:57 AM

Use a Scangauge to find out what fault it's reporting.

NachtRitter · 03-22-2009, 04:53 PM

Presumably, you've checked all the obvious things, like connections, state of battery, etc?

SVOboy · 03-22-2009, 04:58 PM

Can you cross the jumper and tell is what code it is throwing?

Christ · 03-22-2009, 08:23 PM

No, just check your grounds. The main fuel relay clicks uncontrollably when there is an intermittent ground circuit somewhere, usually the one that connects to the water neck housing (thermostat housing).

Check/clean/replace every ground you have, clean them all, then go do try to start it again. It's a pretty common problem, honestly.

Christ · 03-22-2009, 08:23 PM

Oh - you could also have a bad battery.

oldertech · 03-22-2009, 08:47 PM

Success!!! Much has happened since the first post.

I didn't make it clear that the flashing was not normal code flashing, it was a fast flashing, like something was very wrong, along with the clicking of the ignition relay. Turned out I had indeed missed the ground wire that goes from the engine loom to above the thermostat housing. Hooked that up, had a momentary panic when it tried to start, and revved rapidly. Close! I had switched two of the sensor connectors, the one to the IAC with the vacuum solenoid. Then it started and NO CEL!! Yeah!!!

For the road test and I was hoping that I'd have a Shift Indicator light. No light. And nothing really felt different. I did the paperclip in the engine diagonstic connector and the CEL didn't act right when turning on the ignition.

Fortunately I had another 49state P07 ECU. Hooked that one up, took it for a drive and lo and behold, the CEL passed the paperclip test and on the road, Leanburn!!! It's amazing that 14 years after the car is made, and over 220000 miles, the engine can now can do what it was supposed to do in 1995, staying true to it's design.

OK, back to the SIL. I took our "replacement" instrument cluster out. We had had a speedometer failure when we got the car, and the junk yard sold us a true 49state speedo cluster with the white box surrounding the SIL, unlike our old speedo. I pulled out speedo out and saw that there is a socket that had nothing to connect to. Reading the wiring diagram I see that there is a 5-pin connector that we are missing on the California-spec loom. I'm sure that I can run a wire from the light to the ECU and get the SIL to work, but I'm wondering, did the VX and CX have a separate wiring loom to the 5-pin connector that I'm missing? Or was there a 5-wire connector in the instrument cluster loom that they just left out. Amazing that a car designed for a single state would have a different dashboard loom AND engine loom from the 49state car.

Wrapping up, it seems that the 49-state engine loom will indeed mate with the california body and give you 5-wire a and leanburn. Very exciting! The rewiring of a secondary loom with junkyard connectors project just seemed too cumbersome for me.

Now that I'm experiencing leanburn for the first time, I'm detecting that it works in all gears when the car is warm? What are the parameters for it's operation? Fully warm cat? When driving around town I can be moving along with a light throttle and give it a slight bit more gas and feel a gentle increase in power. It's brilliant. Does anyone ever wire up a light to show you when leanburn is engaged?

That's about it for today. Haven't done any mileage checks yet because we just were driving around town.

Scott

SVOboy · 03-22-2009, 08:51 PM

I think the parameters are just a warm o2 and low load.

Good job getting it working

turbothrush · 03-23-2009, 11:55 AM

To monitor leadburn in the Vx I installed the Autospeed Voltage Monitor kit which is 10 LEDs that indicate AFR by measuring the voltage of pin D14 on the ecu. I guess a single light would work almost as well but I found it easier for me to just get the kit . And yes the leanburn seems to work in all gears even accelerating ( engine warm ) if you do it veeerrry slowly. Not sure yet if it is better to accelerate briskly and cruise in leanburn or acelerate very slowly in leanburn. I plan to test this as I also have the MPGuino Kit which gives instant feedback

oldertech · 03-25-2009, 02:21 AM

Thanks for the leanburn tips! Our first tank, combined city highway yielded 48.54 MPG. Learning how to drive with a totally brand new car!! Learning the ins and out of Leanburn. We have lots of road trips this week so we can get more data. It's amazing! That's about 10mpg higher for an average than we were doing with the California spec engine. Course that was one tank. Our mileage will vary

I'm going to RadioShack tomorrow and shop for a green LED. If the new Insight can have fancy lights indicating an economy mode, so can I!!

Scott