I have a question...

I purchased a 95 Accord LX 2.2 from a buddy of mine. He said he replaced the main engine wiring harness in it, and I tend to believe him as it now has ABS pigtails to hook up, but this car does not have an ABS brain or modulator on it.
Long story short, I have the dreaded CEL on so i jumped the blue 2-wire plug and got a 65. Got it, it is the downstream HO2S...

The funny thing is, I cant find any 95 Accord 4 cyl out there that has a 2nd O2 sensor when I do a parts search....

Is it possible that he put in a harness from a 96 as I know they have 2 sensors?

If that is the case, should i put a 96 cat in so i get the O2 port and wire one in? Can i replace the ECM with one out of a 95 and be good? Will the plugs match up? Shoudl i change the harness?

Ideas? I know that O2 sensors can be bypassed... And I read that I can do that with a 30ohm 6W resistor and am comfrotable doing that, just could use some heading as to which wires... I have wiring schematics for a 95, but not sure if it changed going to 96..

Any help would be greatly appreciated.

 

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well i ordered a 5w 27ohm resistor from radioshack... gonna give that a whirl. i will keep everyone posted for those that care.

 

That O2 sensor is near the catalytic converter. There's one on the exhaust manifold and one by the cat.

Which for an EX is here:



http://www.hondaautomotiveparts.com/...T+PIPE+%281%29

#31

What ECU is in the car?

 

im not sure which ECU is in there... I should have checked when i replaced the carpet...

I will pull the carpet back and look... I do know that it looked pretty rough on the outside (corrosion/rust).

I also noticed I have another short now... With the car running, the dome light and right door courtesy light along with the door ajar idicator partially light up... so another thing to research.

 

You may need to adjust the striker plate on the car , my '97 had an issue where it would get out of spec and think the door was open. Try moving the striker a bit closer to the vehicle. Should have just two phillips head screws on it holding it in place.

 

Most likely scenario is the harness/ECU are from a 96. That would have required various other changes to the engine as well. Call up your buddy and ask if he had to change the dist, front cover, etc.

 

Ok, well no downstream o2 sensor on this 95 LX... Just the one on the manifold...
Pulled back the carpet and was very upset...
Here is the ECU



The date reads Apr 1997, so clearly not a 95 ECU....

OH and look what is just plain missing...

Do I need to have a TCU?

 

That is a 96-97 Accord LX Auto ECU.

The OBD1 (94-95) CD Accords only used 1 O2 sensor. That is probably why you could not find the second one.

That OBD2 ECU has the tcu integrated into it. That is the blue connector on the OBD2 wire harness/ECU.

Now you can ether try your O2 bypass or you will have to add/find the secondary O2 wire harness/connector and add the sensor. That will be hard if you are still running OBD1 exhaust setup. There will be no bung for the second O2 and it will have to be added.

 

Thanks for the info Ghost...

I think I will just try the 5w 27ohm resistor and see if that takes care of it... I am so glad I don't need to get a TCU ...

On a side note... I think I figured out the passenger door courtesy light issue... It's only on when the radio is on, so I think there is a short between the power antenna wire and that circuit... Gonna have to do some tracing

 

Ah good old electrical gremlins! Patience is the key with tracking them down.

That is some pretty wicked corrosion on that ECU. What does the rest of your under dash wiring look like? Was this thing in a flood? If it was, I would drop it like a bad habit.

Best of luck!

 

The ECU came from a different vehicle... But this car did sit in a field for a it with no back window, hence the reason I replaced the carpet...

It's a project car to say the least

 

I don't suppose anyone knows where I can get a pin out for that ECU?

 

Never mind, just found one that you posted Ghost...

Looks like
A5 is for secondary o2 sensor
D13 is the secondary o2 sensor ground
D14 is for the secondary as well...

I know this is a heated o2 sensor, but I don't care about that... I think the d14 is for the heater, so I would place the resistor between a5 and d13?

 

A5 - Secondary O2 sensor heater circuit
D13 - Secondary O2 sensor ground
D14 - Secondary O2 sensor signal

I have never done the O2 bypass, however I would assume that you are looking to tap into D13 & D14.

 

Ok so tried a 27 ohm and a 30 ohm 5 watt resistor on d13 to d14 and a5 to a10....
Nothing....
Went to junk yard and bought a new/used ECU to replace it out of a 97...
Still got the darn cel and still pulling 65.

Could really use some help from anyone that has done a successful secondary o2 sensor bypass.
I would need to do the bypass at the ECU as the harness for the secondary o2 sensor doesn't exist on this car...

Any help is greatly appreciated.

 

So found out about an obd2 simulator at http://www.ubertechnics.com/o2_simulator_2.5.aspx.

Only $30, so I figured I would give it a try... I read a success story on here for a 96 civic, so we shall see.

I'll keep everyone posted.

 

Well good news, the simulator is working like a charm, and very easy to hook up.

So no more cel!!!!
But I can't win for losing, driving the car today I noticed some clicking from the drive train when turning... So I got online at rock auto and ordered new half shafts along with some lower ball joints. Figured I might as well replace those while I am at it.

So looks like next weekend is booked up now.
Just wanted to say thanks for all the help everyone has given.