Hello all! I am stumped. I have a 1995 Honda Civic VX. It has a feature that makes it go into "Lean Burn" It has the VETC-E engine. It was not going into lean burn when I got it. The check engine light was on for a Code 48:Lean Air Fuel Ratio. I replaced the upstream O2 sensor. This shut the light off. The car then went into lean burn. However, here it the problem... when it goes into lean burn, it starts to skip or sputter like it has a miss. As soon as I step on it, out of lean burn, it goes away. Or if I unplug the O2 it runs good... but no lean burn. I thought it was not getting enough spark. I put in Hotter pluggs.. Bosch Plat 2. I replaced the wires, dist cap, rotor button and fuel filter.

This did not help.

I disconnected The EGR, and ran it.. same result... cleaned EGR anyway.

This did not help.

I used seafoam on the intake... and in the fuel.

also tried Lucas FI cleaner

Did not help.

Can't figure it out.. No codes.. could it be a faulty o2

It's a 95 Civic. New air filter too by the way 190k miles. T-belt done around 150. Cat appears to be fine, no red glow or anything. Any suggestions would be greatly appreciated.

Thanks,
Ken

 

Fuel pressure could be wrong. Check with a gauge. Make sure you have the right O2 sensor, I don't know about the VX but the later HX models used a different (and expensive) sensor vs. the same years DX or EX. You could remove the injectors and clean them manually, potentially a lot more effective than magic in a can in the tank.

 

How long have you owned the vehicle? Is this a recent problem (assuming that you have had it for awhile)?

The VX uses the 5 wire o2, just like the 96-00 HX models. I assume you replaced the sensor with the correct replacement?

 

It is the right o2... very expensive. I've had the car for only a few months. the check engine light was on from day one. I figured it wasnt a big deal. I was getting like 36mpg. then I found out about it could get like 45+... just replace the o2.... Compression is outstanding and even. I'm leaning towards fuel injectors leaking... any thoughts?

 

Hello, just picked up a 93 VX last week. It runs great when cold, but as soon as it warms up and gets into open loop, it starts to sputter just like yours does. As soon as I give it some gas, it seems to get out of lean burn and runs fine. It looks like the first o2 sensor was replaced. Could these problems be from cheap o2 sensors?

 

Most likely. How many wires are on your current o2 sensor? Can you unplug the sensor and see if it drives any differently? You will get a check engine light for the o2 not being plugged in, but if it runs fine without, it is almost always the 5 wire o2 sensor at fault. I was lucky and found someone on a different forum selling a barely used one for like $175.

No one says it is cheap to keep these lean burn vehicles sipping fuel!

 

I'm having problems with a '92 VX that I picked up for my kid. When accelerating it runs fine, but when you get into a steady throttle situation ie: on the freeway at a consistant speed it acts like it's leaning out and dying then if you press the throttle it picks up with a jerk and runs fine. I can't get it to pass the Ca. smog tests 25 mph test because they can't hold it at a steady speed. Anyone figured this problem out yet?

Take Care
Troy

 

Does anything change when you unplug the O2 sensor? A CEL will come on, but my issues (when I had the VX last year) went away once this was unplugged. I will post in your other thread.

 

I have found out, this is the EGR ports. If you unplug the O2 it will run fine, but the CEL stays on. It will NOT go into lean burn. I need to have the egr ports cleaned, but it appears to be above my skill set. Let me know if this works and or helps. Thanks

 

So I've delt with it for a while, but I'm going to take some time and fix it. When I unplugged it, it ran fine with a CEL but I don't think it was going into lean burn mode due to no o2 sensor signal. I'm planing on cleaning my EGR ports either way, so I'll let you know if that helps. I have had a CEL for codes 41 and 48. I took a quick look at my wiring and it seems to be good, but I would like to test it to make sure. I'm not sure what o2 sensor I have either. It says l1h1 japan with 1624 on the socket part. I don't think it's OEM but can any one identify what o2 sensor it is?
Also, does anyone have a known good o2 sensor around the lancaster, PA area I could try!?