What up everyone this is my first build. 1989 Jeep Cherokee limited. I'm slowly getting everything fixed and noticed that there was a broken sensor on the left side of the block above the oil pan.I bought a new sensor and it looks nothing like it. Is it possible they have made upgrades? Also would a bad nox sensor cause my yeep to back fire and die? I took it to a shop and not a single code came up not even the broken sensor. To be honest I'm kinda lost what to do next any input would be awesome

 

1989s have no stored codes.
On the driver's side of the engine just above the oil pan is a KNOCK sensor. It will not affect backfiring or any other driveability issues.
Above that is a CTS, coolant temp sensor, which tells the computer the engine temperature.

 

What does the knock sensor do? And would you know what would cause that

 

Is it backfiring out the exhaust or the intake?

 

What does the knock sensor do? And would you know what would cause that

 

I'm pretty sure its out the exhaust

 

I did also put on an aftermarket muffler

 

The knock sensor detects pinging and sends a signal to the ECU to retard the timing a little as needed.

There are MANY different things that can cause the backfiring.

When's the last time the Jeep had new plugs, wires, cap, and rotor?
Have you ever checked fuel pressure with a gauge?
What's the conditon of all the vacuum lines on the engine?
Have you ever snugged up the intake manifold bolts?

 

The cap and wires are brand new and I cleaned the rotor up cause there was a little corrison I'm replace the bplugs this week. I will check the bolts and the only vacuum line I'm worried about is the hose from the top of the valves had a crazy bend in it been have trouble finding a new one

 

If the line from the valve cover to the intake manifold is kinked, cracked or anyway messed up, your idle will be affected.