Hey I recently got conned when I bought a 2004 jeep grand cherokee laredo off craigslist. Anyway I really love it and its my first jeep so I really want to keep it. but it seems to be turning into a can of worms thats costing mucho dinero.

I have the code p0505 - I have replaced the Idle air control valve and the tps as well as cleaned the throttle body.It has a bit off a rough idle but i just want to clear the code. Do I have to buy an ECU or PCM? its the same unit right?

As for the other three codes, p0031, p0051, p0136.
I have replaced all four o2 sensors. I was still getting the code. I checked the o2 sensor fuse and it was blown so I replaced it and it gets blown right away. Is there a short somewhere in the wiring? I have been reading some problems occur when the wire hits the exhaust and shorts out. I will see if I can find a short but am i on the right track or is it something completely different.

Off topic but also in the fuse box for the 20A OSS module seems to be loose and wont get a solid fit. any suggestions or just get a new fuse box?

Appreciate any help i can get. Thank you

 

ok so all the wiring looks good.

I put another fuse in and plugged in scanner.

*No Codes*(0xygen sensor codes, still p0505....)

Turn off car. Check fuse. Fuse is good. run scan again. *No Codes* again

turn key to start ignition.

fuse blows and above oxygen codes appear again....

code scanner suggests new PCM among wire damage(which i checked) I am going to get a multimeter and check the 02 connectors.

so here is my plan.

Replace PCM
Replace Throttle body
Replace TPS
Replace IAC Valve

will doing that at least clear the p0505 code??

Would fuel injectors trip any of this?

It is a 2004. inline 6 4.0 jeep laredo. with about 135000 miles on it and ZERO maintenence done to it... So needless to say the fuel injectors need replacing. but would it make any codes appear?