$100 Civic VX 5 wire O2 / LAF sensor. will it work?

[slownugly]

Well I had it up on the lift and someone installed new struts in it. ( autopart international) so I ordered cheap eBay springs and I'm going to use them with the struts that are on it. 1.75 drop in the front 1.5 rear non adjustable

[greasemonkee]

About 10 years ago I bought some local parts house struts and it actually raised the car on my Integra, they were garbage, then I went to a couple different aftermarket springs to achieve a mild drop. Without coilovers of adjustable shocks (height-wise) you're taking a wild guess. The Koni Yellows do have adjustable perches which is a non-coilover solution. I would recommend being careful with Ebay parts, the quality of some no-name parts is questionable.

[slownugly]

Yea eBay cheapies don't have the best reputation. But I figured I would give them a whirl. I work at a shop so labor is free and if they don't sit right or perform right I'll invest in some good ones. But I'll include pics and what not when I start a project thread

[Superfuelgero]

Originally Posted by slownugly

i just joined the forum a little while ago hello everyone. i wanted to wait til i fixed my vx til i joined so i could help others out with this terrible stumbling problem. anyhow im not going to get into the past repairs i did because they are irrelevant. when i got the car previous owner was trying to fix the stumble and could not. It had a new oxygen sensor ntk with the matching part number so i figured it was not the problem. it ran fine cold, when it got hot it had the common stumble and when o2 was unplugged it ran fine.

luckily i have a spare vx laying around to compare some stuff with. the factory calls for the A09 part number oxygen sensor. the one i am working on had an A08 number but my spare one had the A09 which that previous owner replaced with new. On top of that he had the old one in the glove box and that was also an A09 number. sooo i switched the A09 to the one i was having the stumble with and voila stumble was gone (after i reset the ecu first) On a tank of gas with the A08 i got 44mpg but that was affected by the low power problem and me having to increase the throttle position to gain power. i should be over 50mpg now with a smooth transition into and out of lean burn

in my first experience with the vx stumble i would go ahead and get the honda factory sensor/ or A09 ntk sensor. fix it right the first time as many would say.

The reason is the A08 has a pump current of 4mA where the L1H1 and A09 have a pump current of 6mA.

[jlk16188]

So i decided to waste $400 to test this whole theory out for the sake of argument.

I have a functional, Bosch i believe, 5 wire O2 sensor that i bought and installed roughly 33,000 miles ago. The senor works fine. I average 47.7 MPG per tank for the last 10 tanks in a row. I would compare more but I have had other mechanical issues causing my last 30,000 miles to be troubleshooting mileage. The car operates fine. Stumbles a little at idle when hot and seems to misfire or jerk at high loads in lean burn. It is noticeable when entering or exiting lean burn but you really have to be expecting it to transition in order to feel it.

So, I bought the OEM Honda O2 sensor from Majestic Honda in RI for $425.25 shipped. I removed the known working and good condition aftermarket O2 sensor and replaced it with the OEM honda one. First thoughts were the sensors look IDENTICAL minus the numbers on them are different.

I have only driven 60 miles on the new sensor so far but here are my first impressions. Exactly the same MPG's maybe even 1 MPG worse than my normal commute. Lean burn transitions are not noticeable at all unless under heavier load when I can feel a torque drop but no shudder or slight hesitation when going lean as before. No more shudder or rough idle when hot. Weight reduction due to the $425 less in my wallet

Overall, was it worth it? That has yet to be determined. My old sensor would give me good days and bad days by which I mean some days it was effortless to average over 50 MPG on my daily commute while others for no particular reason I would struggle to get 45 ish MPG on the Same route, same gas, same pump, relatively same weather conditions, The car just felt like it didnt want to run optimal that day. I am hoping the OEM sensor will cure this so I have all "good" days averaging over 50 MPG on my daily commute.

I will keep everyone posted. I did fill up my gas tank just for the purpose of tracking data after the sensor swap. I am really hoping I didnt just wast $425 after already spending $100 something on an aftermarket one that still functions well.

Keep in mind, my results will be slightly off due to my geographical location...central and western Pennsylvania, I drive up or down hills constantly, there really is no flat ground here and I have a 96 civic CX hatchback transmission rather than the stock VX trans.

[jlk16188]

First tank looks promising. I drove from Pittsburgh to Baltimore without stopping and averaged 52.7 on the tank for 410 miles. Keep in mind this is with a 96 civic cx transmission rather than the stock Vx transmission.

Overall the car seems to perform about the same as with the aftermarket sensor. I am still feeling some misfiring like jerking at heavy load in lean burn as before with the aftermarket sensor and still have some hiccups at idle when hot.

The only benefits I have seen so far is the oem sensor transitions in and out of lean burn so smoothly I can't feel it and have to watch my mpguino to know if it has happened. It also seems to run more consistently than before


I still cannot determine if it is worth spending $425 on vs the $100 sensor. I'll keep updating as I log fill ups.

[mbolton1990]

Wow so so far the consensus is the OEM transitions smoother in and out of lean burn yet achieves the same MPG as the $125 one?It's gonna take alot of gas saving to recoup that $300..Great study though,I'll be watching this.

[jlk16188]

Originally Posted by mbolton1990

Wow so so far the consensus is the OEM transitions smoother in and out of lean burn yet achieves the same MPG as the $125 one?It's gonna take alot of gas saving to recoup that $300..Great study though,I'll be watching this.

There seem to be two major differences that I have noticed between the two sensors:

1. perfectly smooth and undetectable lean burn transitions with the new sensor
2. no more good vs bad MPG days. I previously had ups and downs days of 50+ MPG's vs days that i struggled just to get 45 MPG and I truly mean struggled. I didnt want to allude to this yet but I do believe I have all "good" days now.

[jlk16188]

Results from the OEM O2 sensor are looking good. The weather is changing and getting much colder now than the last few weeks but I have managed to pull 5 tanks in a row over 50 MPG average. I have never been able to achieve this before