My 1991 s10 blazer is 4wheel drive 4.3 six cyl automatic and I need to replace the map sensor and O2 sensor. I know where the map sensor is but not the O2 sensor. I am wondering if I will be able to change that one myself. I have degenerative disk disease, carple tunnel and ....lol wow I'm a wreck! So anyway, yeah if you have a minute to let me know where it is that would be great.

THANKS!

 

The O2 Sensor is on the exhuast pipe just past the passenger side exhaust manifold and before the CAT. The hard part with the O2 Sensor is getting the connector unpluged and pluging in the new one. The connector is on the right side side of the transmission and can be a real bear to get at. The actual Sender is not that hard to remove itself. For both you will be laying on your side so you will have to decide if that is something you are able to do.

 

Thank you so much for answering back so quickly, I've just been hangin out waitin to see if someone would because if I can change it at the parts store and ^_^ it solves the problem, then I will be able to make the drive back to the outer limits of civilization where we currently have exiled ourselves without having to wait for an hour or so at each random spot my truck decides it has had enough of the little tricks I use to keep it from stalling and wont start period! Sigh, my Sis said she would help me if I would trade the truck in on a little economy car.......T-T
I'm starting to think I'd have to be a moron not to take her up on her offer.


BUT I REALLY <3 MY LIL CHEVY BLAZER


[quote]mr.vls/1989 S15 Jimmy (DD) with 415K Miles, GM Factory Rebuilt Engine/Trans. New Paint, Headliner, New Suspension Bushings, Eddlebrock Waterpump/Shocks, Adj. Fuel Pressure Regulator and in line Fuel Gage, Injector Spacer, K&N Air Filter, Stock Exhaust, Michalin X-Radial Tires (215/70) Stock Rally Rims, Pioneer Head Unit, IPOD Adapter, Pioneer 4X6 Plates in the front, Pioneer 6X9 5 way sp Rear, 8" Clarion enclosed amp & supwoofer, 10 Disk CD Player. ABS Headliner, Original Owner. [quote]

Nice!!!!

Maybe having over 200,000 on mine doesn't have to mean it's ready for the scrap heap.

just means I'd better learn more about fixin stuff on it!! ><

 

You need a wrench that will fit the O2 Sensor or a O2 Sensor socket. (I do not remember the wrench size) You can always size it up at the parts counter. The wire is a single wire coming off of the O2 Sensor to the connector by the side of the Transmission. To disconnect you need you be able to lift the retainer on the connector to unplug the pigtail. You might want to spray the base of the existing O2 sensor with PB Blaster and let it soak for a while prior to putting a wrench on the sending unit. Unpug the O2 sender, remove the O2 sensor from the exhaust pipe. Install the new O2 Sensor and plug the pigtail into the connector by the side of the transmission.

 

If you drive to the parts store the hard part is going to be the hot exhaust. You might have to hang around a while for the exhaust to cool off before you will be able to reach up and unplug the connector. You could probally wrench off the old O2 Sending unit before the exhaust is cooled off.

 

does anybody know if its in the same location on 2.8 87?

 

My factory service manual for 1989 indicates that the O2 sensor for the 2.8L engine is in the same location as the 4.3L engine. (Could be the same for a 1987)