lca13's 93 California VX Thread

[lca13]

D8 to chassis ground is 5.6 V. About 2x what it should be according to some other posts.

I just called Honda to see if I could purchase a ecu test harness (plugs between the ecu and the existing wires allowing you to inspect each pin while the whole thing is plugged in). He laughed ... before he quoted the price.... $800.

[lca13]

OK I think I have the wires right (heater ground simply had to go to A23).

Now the test voltages appear consistent with all the data in the forums.

So I think it is right but it seems extremely aggressive going into lean burn and the engine then misses.

What is interesting about this is that I have experienced three different lean mode bahaviors depending on changing one wire:

heater G to chassis ground: agressive lean burn and missing but driveable
heater G to D22: milder lean burn, some missing but quite driveable
heater G to A23: very agressive lean burn... not as driveable.

The latter, heater G to A23 is the spec location. With this I get the desired reference voltages listed elsewhere in this forum. But obviously something is still wrong... continue to think grounding obviously. time to recheck the wires for the 11-teenth time and I also plan on doing all the Helms troubleshooting to see if anything stands out there.

[GasSavers_TomO]

I'm pretty sure of this but you have fresh OEM plug wires and the correct NGK spark plugs and correct Gap right?

[lca13]

I did check the plugs... they are correct based on your's and other posts.

Here's the thing... it is all basically working and I have gone through "all" the Helms troubleshooting procedures and all the voltages and resitances are correct.

But, the D14 to D16 voltage.... the stuff that should indicate rich, stoich, lean... is correct when cold (-0.78), then varies like expected during warmup... but under speed down the road it keeps leaning up to 1.2 volts or so..... the engine runs ok about to, say, about 0.9 v... but the higher the worse ir runs.... Also, complete deceleration with no throttle reads 1.45 which I take is the zero fuel case.

Again, it is behaving sort of right and the readouts are. for example, after the rough running at 1.2 v... when the speed slowly drops, it then drops out of lean burn (you can feel it power up) and the voltage readings drop to, say -0.4 to -0.1 or so, indicating now rich.

Tell me about the 5 wire O2 resistor? Mine is reading 7.5K ohms.... how is this used?

Basically it is working but the ECU is just pushing the lean condition too far.

[lca13]

also thinking about why three of the leads are shielded in the harness to engine section.

Tonight on the way home I had a long throttle closed deceleration and the volt reading went as high as 1.9V (almost never higher than 1.5V prior)... and then at the bottom of the hill the CEL came on..... shutdown and restart... no CEL.

So I've got a calibration thing going on. Whether grounding, shielding, or maybe the O2 is also near the end of life... who knows but I sure am having fun. Consumed maybe a better word :-)

[GasSavers_TomO]

The Calibration resistor is jut that, a calibration that the ECU sees to compensate for variances in production of the L1H1.

There was another VX owner that was getting some high/lean readings like yours and found out the O2 was coming to the end of the line. It would suck for you if this was the case since I just sold you that O2 and it did work fine in my car.

I'm glad that you are having fun being the pioneer in the swap to lean burn though.

[GasSavers_TomO]

Oh, hey, forgot to add....Try cleaning your EGR and EGR ports in the intake manifold. There is an EGR cleaning kit for The accords, and I'm going to check if there is one for the Civics as well. I clean mine by taking off the EGR valve and the spraying CARB/Choke cleaner into the ports with the little red straw. The symptoms of clogged ports are stumbling under light load and highway speeds.

[lca13]

>> It would suck for you if this was the case

Too funny.... but if I just hooked it up and it worked, what fun would that be? What amazes me is how anybody has figured this out. For example, each of the interesting O2 sensor connections is referred to by up to 4 different names in the vaious materials I have looked at.

VS+, VS, VNB sense
IP+. Pump current
IP-, VS-, VS/IP, common

At least I will have all this info wirtten down and correlated for other adventurous souls soon :-)

[GasSavers_TomO]

Be sure to check the condition of the 3 grounds for the engine Bay:
The negative cable of the battery to the passenger shock tower
The transmission case to the chassis on the passenger side
The driver's side of the valve cover to the chassis behind the driver's side headlight.

There is an additional ground point on the thermostat housing towards the firewall below the Distributor. This ground point is for the Distributor sensors and Fuel injectors IIRC.

Make sure there are no frayed wires or corrosion on them as well as making sure that they are tight.

[lca13]

Actually I super-enhanced those ground wires a while ago after the local performance parts shop (one of those "big on the web" small store in front places) to me about this.

Get this: I went in there to maybe buy an intake... a header... ready to spend some money and the guy told me to get the Sun ignition ground thing... $100 and nothing else and I would notice a big performance improvement. The web research indicated a lot of positive results as well, so a couple of weeks later I supplimented each of these three grounds with two strands of 10 gauge copper, cleaned all the connections, got a heavier battery to chassis cable... I noticed an immediate responsiveness improvement just like he said I would. More than I would have expected but it was clearly there.