I installed a set of hooker super comps about a week ago. When doing so I extended my engine harness for the oxygen sensor connectors myself instead of paying whatever it is for peices of wire that do the same thing. I bought the headers for 250$ and they are ceramic coated. I didn't want to ruin the headers so I bought a set of reducers and but the o2 bungs in them. I'm having a problem with my car getting into closed loop and staying their now. When it goes into closed loop, and I let off the throttle it goes back into open loop. Then I have to give it a lot of throttle to bring it back into closed. My Bank 1 o2 sensor seems to be working properly. When the car eventually goes into closed loop it switches between .3 and .8 mV. Bank 2 on the other hand is staying at ~.47 V. To me it seems like something isn't right only because bank 1 is being read in mV and bank 2 is being read in Volts, according to my scanner. Can anything other than wiring cause this issue? I will be sure to triple check my wire again, also. Any other ideas would be appreciated, thanks!

 

Switch the suspected O2 sensor to the other side. If the problem follows the sensor it's the sensor; if it doesn't it's the wiring.

O2s are finicky. When you make your own extensions you run the risk of altering the resistance of the signal wires, which the PCM will freak out about. For every person who has tried it successfully there are two who tried it only to have O2 issues and end up getting the extensions.

 

Ok, I will try that and repost. I didn't extend the o2 sensors themselves, I extended the o2 pigtails on the engine harness.

 

Bank 1 still read in mV and Bank 2 is still reading in volts. Which one should it actually be reading the o2s in Volts or mV?

 

Pudding, mmmmmmm.

 

if there is a connection before the O2 as you say, could it be leaking? I think that an air leak could goof up the sensor...

Other problem might be that the 'burn-off' from the new coated headers fouled the one...

 

I can double check that the reducer and gaskets are not leaking in the morning.

Is there a way to test the the o2 harness that I extended? If so which wire should I check and how many volts should it/they show?

 

Had a buddy come over and we knocked out rewiring both extensions I previously made. I guess I did a horrible job for extending the o2 harnesses. Anyways, took the car for a drive, through a code 13 - bank 1 low voltage. Came back swapped o2s side to side. Took it back out and threw code 63 bank 2 low voltage, replaced the failing o2. I'm a little strapped for cash, especially throwing down 100+ $ on o2 sensors so I only bought 1. The car is now going into closed loop, but it's still bucking when I give it more gas when I'm cruising. It also idles like complete garbage. Any more ideas would be appreciated. I'm kind of leaning towards the other o2 being "lazy", but unsure of the symptoms it would cause.

 

Bucking sounds like a missfire. Burned plug wires are common on freshly intalled headers. Also make sure they are all plugged in correctly.

 

If it was misfiring would it throw a code on an obd1 car?

 

And last night I popped my hood and saw the metal boot protector arcing off the number 7 spark plug. I pulled it off, and checked for anything else arcing and didn't see anything.

 

Neeeeeewp. No crank position sensor on OBDI so it will not show SES light.

 

I agree with this, the headers need a few heat cycles on your old o2's so that the coating burns off and then your switch to new o2 sensors.

$100 on new sensors is ridiculous. I sincerely hope you didnt buy Bosch. You can get Denso's all day long for $35/piece.

 

When it comes to O2s, AC Delco's are definitely worth it, IMO.

 

did you solider the harness? Did you clean all your wires with flux, if you have a plug boot arcing that will cause the buck ....

 

I can't disagree with that, I will only run those or the Denso's.

 

I bought a denso. 48$ at local parts store with my dealership account. Taking the metal boot off the spark plug wire made it stop arcing but didn't fix the problem. And I ran the car for the last 3 weeks with old o2 sensors which I would imagine would be long enough for the ceramic coating to burn off. Is it possible that the car running rich could have fouled a plug/plugs out? Wong have time to really check for anything until Saturday night since I work 3 14 hr shifts.

 

sparkplugs.com has the Denso's $34/piece