pantdino

Someone took off the CA cat and headpipe and put on a header (no cat) and 49-state headpipe with the secondary sensor in the headpipe.

I see the wires and connector to the secondary but not the primary

here's photos of where the secondary wires arise from--

is this where the primaries arise also?

Can anyone take a photo of where their primary wires arise from and post it?

The white wire from the secondary sensor has been overwrapped with black shrink coating, so it is black exiting the harness-- a little confusing

Thank you

ezone

Well THAT looks hacked.


I'll try to get back on later and look up some wire harness colors....Gotta run now

ezone

Ok...

Got pics of that header mess and the sensors?
The connector shell I can see looks like it's for the secondary sensor.

On an LX car, both O2 sensor pigtails should come out of the main harness at the same area, because both sensors are (WERE) located right out front on the manifold/cat assembly.

===========

The primary O2 sensor is an A/F sensor. (It's NOT a regular O2 sensor. It looks the same, smells the same, and does about the same job..... but is very different internally and the computer is different.)


Primary AF sensor: Engine harness wire colors are
White
red
green
red/yellow

The colors of the wires on the sensor do not correspond with any of the engine harness colors. They are supposed to be mismatched.

============

The secondary sensor is a regular O2 sensor. It's supposed to be located in the exhaust stream post-cat.
Engine harness wire colors are

Black/yellow
black/white
white/red
green/yellow

Again, sensor wire colors do not correspond to the engine harness wire colors.

Your pics look like the secondary sensor wiring has been pulled out of the original harness and probably was extended to get the sensor relocated further downstream (post-cat)....Well, if it had been done the right way it would.

Your wiring harness for the primary sensor is probably still right there, just hidden. Try checking all those other harness branches, maybe it's tucked up under that big airbox or something.


And
There's some FAT spots in that bundle, like there are butt connectors (splices) taped over and hidden in the black tape. (pics 1 and 2)...Your primary sensor wiring might be in there, unwrap the tape and see what the original harness wire colors are.

pantdino

I removed the air box and cut off the plastic wiring loom stuff back to the previous Y-- still no wires to the primary.

Here are photos--

two black and 2 brown/yellow wires which go to the ground,

a green (or green/black?) and black going to the thermostat fan switch

a black/yellow, black/white, green/yellow, and the thicker black one which leads to the white wire on the secondary connector

What color wires are supposed to go to the thermostat fan switch?

Anyway, even if the green going to my fan switch is supposed to be going to the primary I'm still missing 4 wires.

I guess I'll have to cut back further into the wiring loom.

One thing that confuses me, though.
In your initial response to my question about the car being a 49-stater, you said it had a 49 state emissions system by code, which would correspond to what I am seeing. Is that right or is the code ambiguous and can be 50 or 49 state?

Thanks again
Jim

pantdino

I googled Honda KA emissions code and there are a number of hits--KA is definitely the "except California" code, so it seems to me I am looking for wires that were never there.

I don't know why the record says it was sold in CA, but it seems to be a non-CA car.

I might have to go to one of the emissions program referees to sort this out.

Or maybe I'll call Honda World in Downey to see if anyone remembers having some kind of exemption that allowed them to sell non-CA cars at one point???

I tried to call the Honda Customer Service line and got on long hold, but I'll try again.

ezone

The plastic covers on the harness looked original.
It didn't look like that area had been messed with. Maybe it has, it's hard to tell from a pic.

Here's what I saw:


(Bow to my mad MS PAINT skillz!)


#1 is where I thought it looked like butt connectors have been taped over.
#2 I thought might have been the wiring for the primary sensor.

#3, I just wondered WTF that is because it isn't original to the car.







I'm guessing not relevant to the current problem.

The first 3 sound right....not the last.
Plain green wire and plain black wire.

What are you calling a "code" here?


In the first response I only had info from a parts catalog lookup. The later response was info from a VIN report through Honda.

The differences between the exhaust (cat) and sensor wiring is only in the EX or LX/HX/DX trim levels, not Calif or 49 state.

On an EX trim the cat is located under the car...
The other trim levels have the cat built in to the exhaust manifold as one piece.

According to the emissions sticker wording, and for all practical purposes right now, there is no difference.

ezone

Does your engine say VTEC on the valve cover trim, or just Honda?

pantdino

It just says Honda

#1 is I think some butt connectors, but it only goes to the thermo switch and only 2 wires enter it

#2 is just the 4 ground wires

#3 is the connector to the battery maintainer I have on the car because it was sitting for a week w/o use.

I seem to have trouble keeping below the 100kb limit but I'm going to try to post a pic of the current wiring situation

ezone

Man, if I had a car to look at I would....but 7th gens are getting scarce at work these days. I only had an image in the wiring diagrams to look at.


I use a pic hosting site, then click the image icon ( at the top of the reply text box) and paste the URL link into the popup..

pantdino

I have now removed the sheath from that part of the harness 4" back from where the wires to the secondary come out

the wires on the right are "newly found" and do contain some white, red, and green, but I need to see a wiring diagram to see what other wires are there with those colors.

(The red butt connector is where I repaired a wire I cut in dissecting the sheath off-- oops.)

ezone

Hard to find diagrams on google images.... It's also hard to find a diagram that shows everything at once. The factory diagrams are normally drawn in small sections and take several pages to cover a complete system.

Found what looks like the right diagram for the o2 sensors

ezone

Get in the old ladys sewing basket, steal the seam ripper. It works great LOL

pantdino

update-- I give up. Took the car to a Honda independent specialist who will try to find the wires but will replace the wiring harness if he can't. He can't start on the car until next Monday.

Thanks for all your help

Jim

pantdino

UPDATE-- Well, I took the car to the local Honda Independent shop and he told me he would have to replace the engine wiring harness and install a cat.
But then he discovered that someone had swapped in an EX engine and harness-- hence no second set of wires to the secondary sensor, since the EX has the cat UNDER the car.

I'm a little displeased because I would think as a Honda specialist he would know an EX engine at first sight rather than ordering a bunch of parts (some of which can't be returned), removing the exhaust manifold and harness and THEN discovering they were of no use because they were for the wrong engine.

Anyway, that's where we stand. His suggestion was to pull the EX engine and put in a used LX engine, harness, cat, etc for $4K. I said no because we have no idea how many miles are on the engine.

I think next step is go to the smog Gold Shield station to see if we can get a one-time 2 yr exemption while we sue the seller for the funds to pay for this.

Thanks for all your help.

ezone

Don't knock the guy, the engines look damn near the same at first glance. (See pics below)

If you went in and told him the same thing you posted in the OP, he's probably thinking you knew what you were talking about: "Someone took off the CA cat and headpipe and put on a header (no cat) and 49-state headpipe with the secondary sensor in the headpipe."

There's one main difference between LX and EX engines that you can almost see from above, that's the VTEC.
You said the valve cover trim doesn't say VTEC, and you weren't able to ID it as an EX either.



Swap the black trim on the valve covers and you cannot tell any difference (until you dig deeper).






I know exactly where to look, and I can't see the VTEC valve in either of these pics at all.

pantdino

I have been looking at pics of the LX and EX engines and agree with you-- they look the same externally. The PO even changed over the plastic cover to remove the VTEC lettering.

Thanks again for all your help