O2 sensors plug into the exhaust transaction of most vehicles. Vehicles manufactured after 1999 annex multiple O2 sensors plugged into the exhaust action. These sensors detector the fuel to air ratio and figure the size of harmful emissions going terminated the exhaust system and mail this material to the leading sensor, succeeding to the engine belief. Then the leading sensor sends the confidence to the vehicle's personal computer.
Maybe the "research engine" bright flicked on in your Blazer. Use a creeper if you have one. Once you've found the sensor you're looking for, follow the wire coming out of it and trace it with your hands to feel where the plug is for it. It won't be more than 8 or 9 inches away.
1. Halt which O2 sensor needs to be replaced. This can be done with a principle reader and there are many repair shops that Testament analysis your codes for no charge. The statute reader should demonstrate which O2 sensor is giving the bad news rule. Determining which sensor is damaging Testament be the most challenging cut of this work. On Blazers manufactured after 1999, there Testament be multiple banks and sensors. The bank succeeding to cylinder one is bank one, so finding where the unit one Glimmer plug in the engine could benefit you figure which side. The higher the cipher the sensor, there very back in the exhaust process it is placed. For instance Bank One/Sensor One would be the next sensor to the manifold on the cylinder one side. After the front Y-pipe on the exhaust method for the Blazer, it channels into a unmarried exhaust before it streams terminated the catalytic converter. Some parts stores Testament posses decree readers and whether you obtain the O2 sensor from them, then they Testament hold a vested excitement in helping you treasure absent the facts you essential and sell you the Correct sensor for replacement. Extremely, test the sensor before you concession to be decided there is a little proportions of anti-seize compound on the threads. Whether not, pay for a slender tube of it at the parts store further. Most condition sensors come with there expert bigness already coated on the threads of the different sensor.
2. Stand the front of the vehicle on a Apartment lodgings, equable surface. It is recommended to advantage van ramps for this, on the other hand you could bag a floor jack and two jack stands to raise the front. Just be sure the vehicle is secure and safe because you're going to be underneath it. Place the Blazer in park or gear and apply the parking brake. Turn off the ignition and remove the keys so no one turns it on by accident while you're underneath. Place a wheel chock behind one rear tire.
3. Crawl under the vehicle keeping the remaining hand tools handy so you can reach them as needed, including the replacement sensor. and examine the exhaust system. The town mechanic scanned the decree and told you it was the O2 sensor. On account of the replacement sensors are generally added than $100 to shop for over the counter, there's no thought paying the mechanic labour charges to assign it in if you retain some local mechanical skills and a infrequent tools.
Instructions
Stare at the new sensor to determine the length. Once you've located the plug, use the small straight edged screwdriver to press in the lock and at the same time, pull the sensor plug apart.4. Spray a small amount of WD-40 on the threads of the sensor where screws into the exhaust system. The check engine light may take a few days and a few cycles to reset. It is recommended that you go back to the parts store and have them reset the check engine code for you and then run the Blazer under normal conditions for a few monitor cycles (may take up to 70 miles or so) to see if it comes back on. You can also try disconnected the battery, but this will erase other data stored in the computer. Try loosening the sensor using the 22 millimeter wrench or the oxygen sensor socket and a ratchet. Give it a good tug, but do not force it off. Usually, if its going to come off, a good tug will loosen it and you'll be able to unscrew it by hand almost immediately. If it does not, apply a little heat with the hand torch to the exhaust pipe around the circumference of the sensor. Do not heat the sensor and the pipe. That would swell both metallic components and you'd be defeating the purpose. You want to make the pipe swell and loosen the sensor. Just a little heat should be enough. Allow to cool once you've broken the sensor loose if you had to use the torch.
5. Remove the sensor and compare it to the new one. If the new sensor did not have a small amount of anti-seize compound on the threads, apply some now. Just a small amount and only on the threads. Do not get any on the sensor head. Screw into the sensor hole and tighten with the hand wrench. You want it tight, but as you've noticed, the sensor only have 4 to 5 threads, so you do not want to over-tighten and strip the threads or you're going to have to buy another sensor.
6. Plug the sensor in until you hear and feel it click. There's only one way it will fit into the plug. Remove the tools and lower the vehicle. Not too much because if it doesn't feel like it wants to loosen, you may have to heat it up with the hand torch a little bit and WD-40 is obviously flammable. The key here is not to damage the threads on the exhaust pipe. If that occurs, you will not be able to rethread the new sensor in tightly.
