Overlength Oxygen Sensor

I have just replaced the exhaust manifold on my 1992 Dodge Colt, 1.5 liter engine. The new manifold’s oxygen sensor hole is 1/2 inch shorter than the stock one, so that the oxygen sensor is now too long. I’ve checked two different manufacturers’ replacement manifolds and each has a hole 1/2 inch shorter than stock; and I’ve checked two manufacturer’s replacement sensors, and each is 1/2 inch too long. The manifold’s hole depth is limited by a cross-piece short metal cross-piece that I assume is there to prevent the sensor from falling into the exhaust system if it breaks. I’ve not known one to break, so my question is: can I drill the cross-piece out to accomodate the sensor length, or should I put shims between the base of the sensor and the maniford to make the sensor fit?

[b]A metal bar across the bottom of the O2 sensor hole? Never seen that!

Is this exhaust manifold cast iron or a welded assembly? If it’s a welded assembly, that bar might be a positioning fixture for when the bung was welded to the pipe. Only it wasn’t removed after the bung was welded on.

Try taking a punch and hammer and see if you can knock that bar out of the opening. Or if you have to, drill it out. You want the O2 sensor tip as far into the exhaust stream as possible.


Thanks for the post. The manifold is cast-iron, and the original had the cross-piece and so did two replacement ones from two different manufacturers. The cross-piece is very narrow, about 3/8 of an inch wide. I’ll try the punch on the original first (it is already cracked) and then, if that doesn’t work, switch to the drill. I’d never heard of this either, but then I’d never had a manifold in the position where I could see directly into the hole before.