I just changed the entire exhaust from the header pipe to tailpipe on my 1990 240dl using all bosal parts. Everything went great until I went to screw in the o2 sensor. The cat pipe had a bung welded in and a plug in the bung so I took the plug out and installed the o2 sensor where it came out of. Then I went to put the same plug in the bung which was welded in to the header pipe and guess what it was a smaller size. First why did bosal send the pipe without a plug and then second does anyone know the size of the threads so I can plug it up. Thank You for your help.
Sal

Where did you buy the Borsal pipes? FCP carries that one and also includes the seperate part# for the small threaded hole. Contact Nick or Scott and get one and be sure to use anti-sieze on the O2 sensor and any plugs.

The small plug may be for the CA market with recirc.

Borsal did not make a mistake they use the same pipe for serval models.

Hope that helps as the plug from FCP Groton is cheap.

Al

I used a plug on my 87 240 for the cat hole,O2 sensor is on the head pipe, and it blew out within a year.
Good luck

Thank you for all the good advice but I am still stumped. On my 1990 240dl the factory put the o2 sensor in the cat. The hole in the header pipe is smaller than an o2 sensor? I have tried the spark plug and it is too big for the hole in the header pipe. What was bosal thinking???

They may have sent the wrong pipe or one size fits several models? Call FCP. Dan

Try an old spark plug, that approach has worked for me in the past.

jorrell
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92 245 250K miles, IPD'd to the hilt, 06 XC70, 00 Eclipse custom Turbo setup...currently taking names and kicking reputations!

The same thing happened to me with my Bosal cat ( the picture on the website I ordred from clearly shows the recessed hex plug in place). Anyhow, I went to napa and they had a cat plug instock (looks and probably is an oil drain plug). It cost $9.50 w/ tax and the threads were correct. That spark-plug trick would have worked great-looks like there is enough room for it to fit.

Where else but on this list could you get a tip like that? You only have to read that one once to know that if the situation ever pops up, you'll remember what to do! Thanks, jorrell.

Wiglaf

No, what he is looking at is not a second sensor bung, but a test port. The test port is smaller. A sensor (and a Ford spark plug) have M18-1.50 threads. The test port is M12-1.25. The pipe should have come with the plug installed.

If it is easier to get one locally, look in the Dorman products section. They offer a range of standard and metric plugs.

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Art Benstein near Baltimore

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