iWare

So this is sort of a continuation of a post i made a while back, this is the link to the original post
https://www.cherokeeforum.com/f2/run...33/#post933818
A brief synopsis is that after I ran a compression check on my engine a while back it started running really rough between idle and about 2k rpm. It sounds a lot like it isn't firing correctly, or it's running soo rich it's causing the engine to not run properly. I checked all the spark plugs seem to be good, and they're definitely in the right firing order.
I just replaced my O2 sensor and reset the ECU with no change at all.

If anyone has any ideas on what it could be: timing, bad sensors, etc. I'm completely stumped.
Heres a link to a quick video I took so you can hear what it sounds like.

VTJeep

both o2's?

VTJeep

all the things i can think of:

-battery
-cap/rotor
-plugs/wires
-TPS
-IAC valve
-CPS
-coil pack
(these last 4 are kinda dependent on year)
-cat.
-o2's
-power/ground wire condition- both the wires and the connectors
-try some sea foam directly into the intake. get a friend to keep the throttle up as you pour in the whole container SLOWLY...

iWare

I already checked the TPS which is good as well as the plug wires.
Why would the IAC cause problems one the throttle is open?
Also wouldn't the CPS just cause the engine to shut off instead of just run badly?
I checked the rotor/cap and it doesn't look new but it doesn't look like it's nearly bad enough to cause problems.

Madrabbett

I have the same issue.
Replaced the cps coilpack and plugs. Still doing it. My mr fixit says the computer. Not that this is ur issue but worth a check

krew

i watched the video and my jeep seemed to run the same way i was messing around one day pulling every plug it turns out to be a injector try pulling the plug on top of the injector one at a time and lisen for the that doesnt make a differents in the way it runs

iWare

I tried what you suggested about pulling the injector connectors. It looks like a bad injector on #1. I pulled the plug on it and didn't make a difference, it did make a difference on # 2. I tried switching the wiring on one and two to make sure it wasn't the wiring.

Are there any other checks/diagnostics I should do while i'm replacing that injector?