I'm researching putting the 4.0L head on my 4.2L engine. On the 4.2L, the O2 sensor is in the exhaust manifold. When I researched the exhaust manifold for the 4.0L Head I didn't see a location for the O2 sensor.
So my question is, where is the O2 Sensor located on engines with a 4.0L Head and Exhaust manifold?
If I put a 4.0L head and exhaust manifold on my 4.2L engine, where will the O2 sensor go?
tia,
bill
There are two O2 sensors on the exhaust on a 4.0. The first one is on the down tube after the exhaust manifold. It is easily seen when under the Jeep behind the driver side front wheel. The second it on the cat converter.
Curt
So for me to put the 4.0L head on my jeep with EFI I would need both the
4.0L manifold plus a section of exhaust pipe for the O2 sensor.bill
Maybe the newer 4.0L (TJ) has two O2 sensors, but there is only a single O2 sensor on my 92YJ 4.0L on the exhaust pipe before the cat. None on the cat.
Terry.
I thought the 4.2 manifolds will fit on the 4.0. I do believe the other way works and can dig up a link on that.
Why not just stay stock or get a header with an O2 port or just kill the stupid computer and get a sweet 25% boost in power without touching anything?
That Ford emissions computer is a bag of dirt when the Jeeps get older. A manually set up machine runs way better and passes emissions.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT'sWilliam Oliveri wrote:
This is a Mopar MPI Mike, not the old computer you're talking about.
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