oxygen sensor?

Question

I’m in the process of replacing a bad oxygen sensor in my galant. I had some trouble removing the old one but finally got it out after letting the car warm up. Now I’m having trouble inserting the new one. For some reason I can’t get it to twist in. Am I supposed to let the car cool down?

Answer 1

Inspect the threads of the old unit very closely. If they are not clean and uniform, chances are that some of the thread from the exhaust pipe came out with the old sensor. If that is the case, go to the local parts store and purchase a 18mm spark-plug thread chaser (they are manufactured by K-D Tools, Lisle, Cal-Van, etc. Perhaps you can get one at Sears.
Go here----->

http://www.toolsource.com/ost/product.asp?sourceid=NO+SOURCE&dept_id=500&pf_id=67798&mscssid=C1P9CNGTXRV19P961N9AP4V02K0V9NF9

…for both a picture and an on-line source.
Use it to clean up the threads in the exhaust pipe, and be careful. If you aren't careful, you can cause some pretty bad damage.
After you clean the threads, use a bit of Anti-seize on the threads of the sensor. Use it sparingly, and do NOT contaminate the sensor nose with the compound. It will ruin the sensor, and you will need to replace it again.

Happy Motoring

Answer 2

Try spraying the threads with WD-40, that will help. Just keep trying, you'll eventually get it. I had the same problem with mine, until I realized I was not lining it up EXACTLY correct. Make sure you have it aligned properly. Work from the top of the car, as under the car, looks can be deceiving.

Answer 3

Why did you start the car with the sensor out? Let the car cool down and hope you can get it in there.....

Answer 4

You might have to re thread the hole. Take the new one to a tool store and get the correct thread pattern.

Answer 5

It should be easier to install when the engine is hot (metal expands when hot). It may be the wrong one. If it has the same thread size, it should go right in.