95 blazer, how many 02 sensors?

Young Savag3 · 08-15-2006, 08:12 AM

ok i have a 95 blazer, and its getting roughly about 10-13mpg. Needless to say, that isn't good. I want to check all the o2 sensors, even tho none are showing up bad on the computer. Anybody know how many o2 sensors a 95 blazer 4.3L 4wd has, and where they're located?? the only thing that showed up on the scanner was an engine knock sensor but i've replaced the driver's side one with a new one and it still says it, so i'm guessing there's 2, anybody know where the other one is located? does a 95 have a MAF sensor??? any help would be appreciated

juddspaintballs · 08-15-2006, 11:58 AM

on my 96 there are 3. should be the same for you. one on each side of the Y and one behind the cat. you might wanna check and see if your cat is plugged up some or dying. you lose gas mileage fast if it is.

Young Savag3 · 08-15-2006, 01:44 PM

thanks for the reply judds, well on autozone website it says i only have 2, but that thing is stupid sometimes. I have noticed tho that while my truck is running my exhaust is pretty rich, no black smoke tho.

blazerbob91 · 08-16-2006, 10:52 AM

Did you check your CPI unit. I had bad gas mileage and it seemed to be running rich. The spider lines wer bad along with the regulator. I replace it all and it got better but I must have been running it to long with the rich condition because my CAT went out not long after the CPI repair.

Young Savag3 · 08-17-2006, 12:14 AM

i was gonna check those this weekend. How do you know exactly when they're bad???

madme · 08-22-2006, 07:29 PM

usualy wen they go they through a code but how many miles are on them? also a 95 blaz will have 2 O2's one forward and one aft of the kat

jetsetjoe · 09-19-2006, 04:21 PM

I replaced both my O2 sensors on my 95 Jimmy last summer (at the same time I replaced the Catalytic Converter that were rattling like hell with loose ceramics, as well as installed an aftermarket muffler).

I remember that my Jimmy had 2 O2 sensors (one pre-cat and one post-cat). The funny part was, all the auto parts stores and the GM dealersship swore that I should only have a pre-cat O2 on that car. So I told them to look underneath for themselves.

Anyhow, I ended up getting 2 Bosch and the fuel economy seemed to improve, but they may have been to the better cat and muffler.

It was hard to remove the old O2 sensors, I ended up taking it to a local shop to have them removed, and even then, they had to clean (via re-tap) the threads repeatedly to get the new O2 sensor installed. But they got it done.

08-15-2006, 08:12 AM	#1
Young Savag3 Registered User Join Date: Aug 2006 Posts: 19 Location: User is: OffLine	95 blazer, how many 02 sensors? ok i have a 95 blazer, and its getting roughly about 10-13mpg. Needless to say, that isn't good. I want to check all the o2 sensors, even tho none are showing up bad on the computer. Anybody know how many o2 sensors a 95 blazer 4.3L 4wd has, and where they're located?? the only thing that showed up on the scanner was an engine knock sensor but i've replaced the driver's side one with a new one and it still says it, so i'm guessing there's 2, anybody know where the other one is located? does a 95 have a MAF sensor??? any help would be appreciated
	[Reply w/Quote]

08-15-2006, 11:58 AM	#2
juddspaintballs I pee standing Age: 24 Join Date: Dec 2004 Posts: 6,282 Location: Union Bridge, MD User is: OffLine	Re: 95 blazer, how many 02 sensors? on my 96 there are 3. should be the same for you. one on each side of the Y and one behind the cat. you might wanna check and see if your cat is plugged up some or dying. you lose gas mileage fast if it is.
	[Reply w/Quote]

08-15-2006, 01:44 PM	#3
Young Savag3 Registered User Join Date: Aug 2006 Posts: 19 Location: User is: OffLine	Re: 95 blazer, how many 02 sensors? thanks for the reply judds, well on autozone website it says i only have 2, but that thing is stupid sometimes. I have noticed tho that while my truck is running my exhaust is pretty rich, no black smoke tho.
	[Reply w/Quote]

08-16-2006, 10:52 AM	#4
blazerbob91 Registered User Age: 60 Join Date: Jan 2005 Posts: 62 Location: User is: OffLine	Re: 95 blazer, how many 02 sensors? Did you check your CPI unit. I had bad gas mileage and it seemed to be running rich. The spider lines wer bad along with the regulator. I replace it all and it got better but I must have been running it to long with the rich condition because my CAT went out not long after the CPI repair.
	[Reply w/Quote]

08-17-2006, 12:14 AM	#5
Young Savag3 Registered User Join Date: Aug 2006 Posts: 19 Location: User is: OffLine	Re: 95 blazer, how many 02 sensors? i was gonna check those this weekend. How do you know exactly when they're bad???
	[Reply w/Quote]

08-22-2006, 07:29 PM	#6
madme Registered User Age: 24 Join Date: Apr 2004 Posts: 322 Location: Oshawa User is: OffLine	Re: 95 blazer, how many 02 sensors? usualy wen they go they through a code but how many miles are on them? also a 95 blaz will have 2 O2's one forward and one aft of the kat
	[Reply w/Quote]

09-19-2006, 04:21 PM	#7
jetsetjoe Registered User Age: 44 Join Date: Jul 2004 Posts: 5 Location: User is: OffLine	Re: 95 blazer, how many 02 sensors? I replaced both my O2 sensors on my 95 Jimmy last summer (at the same time I replaced the Catalytic Converter that were rattling like hell with loose ceramics, as well as installed an aftermarket muffler). I remember that my Jimmy had 2 O2 sensors (one pre-cat and one post-cat). The funny part was, all the auto parts stores and the GM dealersship swore that I should only have a pre-cat O2 on that car. So I told them to look underneath for themselves. Anyhow, I ended up getting 2 Bosch and the fuel economy seemed to improve, but they may have been to the better cat and muffler. It was hard to remove the old O2 sensors, I ended up taking it to a local shop to have them removed, and even then, they had to clean (via re-tap) the threads repeatedly to get the new O2 sensor installed. But they got it done.
	[Reply w/Quote]