Merging threads.

 

Perhaps it's just me, but I found this post to lack certain key facts. While there's quite a bit of information in there, it would help to know if the OP is the original owner of this G and what the service history of this car was? In general, Infinitis and Nissans don't usually exhibit the kind of problems listed unless there was a reason(s). Second, with the large number of electronic failures, I doubt any of us behind a keyboard can accurately diagnose where a short, failed component or defective relay might be. This is a job for an experienced tech to work on.

 

Probably all or mostly due to water intrusion in the box, make absolutely sure it’s dry in there, and remains dry…that’s the main power distribution block, so if it’s wet, you will have circuitry issues no doubt. Also, replacing a blown fuse doesn’t “solve” anything, fuses don’t blow for no reason, if all circuits are operational, without any faults or wiring issues your fuses will outlast the car.

 

Let me restate my thoughts- is it possible this G has been in another owner's hands and exposed to things like flooding or other hazards that could compromise its electronic systems? What do you know about the car's service/repair history?

 

Can someone merge his multiple threads

 

I have owned the vehicle since ~20k. The car has over 100k miles now. The car is well maintained and has been running healthy until this past month.

As an update, I replaced the IPDM with a used part and got the car to start up again. The battery is tested good and all four cam sensors are original Hitachi.

I definitely do have some electrical gremlins. There is a short somewhere since the positive and negative terminals are showing continuity at times. I have an aftermarket stereo with an amp installed so I unhooked the amp power wire which helped but seems like there is a short somewhere. I need to take this to an electrical shop. Any recommendations in the South Bay area in Los Angeles, CA?

The car was running fine, and I drove the car about 10 miles on the freeway trying to get it back home. A CEL came on eventually which I was not able to check. Then things started to get bad. I felt a big jolt and the CEL was blinking with a bad misfire. I got off the freeway and shut it off by a nearby parking lot. The rear engine near the firewall was smoking really bad. I let it cool down for a bit and restarted again, and it was misfiring bad. I checked all the spark plugs (they are NGK Iridium with about 8k miles), and they are in good shape. I pulled the following codes:

P0223 - Throttle/Pedal /Switch "B" Circuit High Input
P0123 - Throttle/Pedal /Switch "A" Circuit High Input
P0113 - Intake Air Temp Circuit High Input

After checking the plugs, I tried to restart. The engine is cranking now but does not restart. When I turn the ignition switch ON and OFF, I do hear the fan running at times like the ECU is not communicating. All the fuses in the IPDM is good. I cannot connect to Torque to read any codes now. Any thoughts?

I am looking to tackle the throttle body and the ignition coils next.