So my coils have been trying to go out (hesitating every now and then) for the past 6 or so months, it has been fairly sporatic and was not a big enough issue for me to justify buying new coils. Well, about a two months ago my car threw a rear 02 sensor code, and within a few days another rear 02 sensor code... well, about a month ago my coils decided they were gonna die out almost completely, so the car was parked until I gathered up the money to buy new coils. What I'm wondering is could the bad coil packs cause the unburned fuel to clog the cat and cause the rear 02 sensors to fail?


cliff notes: Bad coils + unburned fuel = clogged cat and rear 02 sensor codes?

 

It would be my guess that maybe the unburnt fuel caused the o2 sensor to 'flip out' per se...due to high irregular levels of your a/f ration. Take that as it is though, only a guess.


How many miles are on your rear o2 sensor? Mine went out at 50k. ('99 Max)


o2 sensors go out though...whether it is related or not it probably doesn't matter.

 

they're atleast 54,000 miles old... Same ones I bought the car with @ 52k, now @ 96k

 

I assume you got the 'voltage' code for the rear o2 as well as another code?

I would just replace it if the light bothers you. I ran my car for around 5k before I could afford a new o2 sensor. It affects nothing on the car besides the constant CEL light being on.

 

Rear 02 sensor defective on my 97 SE.
Just purchased all 3 even though only the rear is required.
Paid $168.00 at sparkplugs.com with shipping included to N.Y.C.
They are all oem fit/replacement( no wire cutting) and is manufactured by Denso.

This max really flies,only problem is I bel. the ECU has a program informing it that gas is free. If I stay at 70-75 on the highway I can get 375-420 miles from a full tank. Over 75 and I'll be pushing it!

Based on user's exp. I've read here, I'm hoping my gas mileage will improve after the replacement of the 02's.

(97 Black auto SE with VLSD(or something like that) fully loaded with digital climate control, home link leather etc etc. This whip drops undies without me saying a word in the BX!)