So I recently purchased my very first Cherokee! It's a 2001 Cherokee Classic. This thing is sweet, and very clean - but there's a few things that need to be addressed.



I replaced all (6) of my fuel injectors today with one-hole replacements I bought on Rock Auto. I'd love to do the 4-hole upgrade but I'm trying to get this thing to pass smog soon. Anyway, replacement went well and I'm already noticing a tremendous improvement in idle and overall performance. I reset my ECU and so it's still relearning the injectors, and I've noticed substantial amounts of carbon/soot/crud that was getting pushed out my exhaust initially within the first 10 miles or so I tested. It has gone down a lot and I'm sure this is due to my ECU just learning how it needs to behave.

However, since then my check engine light has come on once again. Previously I had a P0174 code (system too lean) and now this code has shown up again, along with P0300, P0305, P0306 and P1196 (02 sensor, Bank 2, sensor 1) I'm fairly certain that some of these codes may have been assessed preemptively, as I haven't gone through the typical 100 miles or so of use after an ECU reset to see what's really going on. But I went ahead and bought a new B2S1 o2 sensor that I'll be replacing soon, as well as some new spark plugs (some of the codes I have were for misfires?! My engine behaves heaps better now..).

OK enough rambling. Just wanted to share what I accomplished today with y'all and see if anyone had comments to make on my codes and where I should go from here. I just bought a Bosch 02 sensor, heard mixed things about them but I figured it wouldn't really hurt to replace it.

 

Steam clean your engine. There are plenty of write ups on how to do this.
https://www.cherokeeforum.com/f30/st...-4-0-a-226299/

Basically take off the elbow connecting the air filter box to throttle body.
warm up engine to operating temp.
Hold revs to 2000rpm and slowly spray or pour water into the throttle body. Yep water.
Go slow. If rpm's drop too much, slow down the water pour.
Do about a quart of water, a Super Big Gulp size.
Drive and smoke it all out.

Then change your spark plugs and O2 sensors.

 

Sounds good Marty, I'll look into that

Thanks!