Hey guys so I just recently bought my 2003 g35 coupe that’s a manual. I took it to autozone to get scanned and a few sensors had to be replaced. I replaced those sensors and took it back to autozone and the same sensors are showing up and the ECU won’t reset. How can I solve this issue because I just spent all this money on sensors and they’re still showing up. Also the VDC off, slip, and abs lights are on. My brake pads are basically done and need to be replaced. Could that be the reason why those lights are on? When I first start the car the lights are off but as soon as I shift gears the car makes this grinding noise from the back and the lights come on. I spoke with a tech from the Infiniti dealership and they said that it’s possible if the car has been sitting for a while that the fluid could get dirty and cause those lights to come on. I really need your input. The sensors I replaced were both cam shaft position sensors, VVT solenoids, knock sensor (still shows up after replacing it) and the 02 sensors. Also getting random misfires and abs malfunction. The abs light and radio blinks and rpm starts to fluctuate.

 

EXACTLY WHAT codes is your car throwing?

It's widely known that these engines DO NOT play nice with the aftermarket sensors so use only OEM Genuine Nissan sensors or Hitachi (the OEM supplier) sensors.

If you still have cam sensor codes then start by getting new Hitachi cam sensors, part numbers CPS0005 and CPS0008.

The knock sensor isn't usually the sensor itself but rather that sub harness it plugs into, here's a link to a new sub harness.

https://www.z1motorsports.com/z1-pro...4ir8q5p21m1c31

As for the brakes, typically it's low brake fluid level that causes the VDC/SLIP/ABS lights to turn on, check your brake fluid level, there is a level sensor inside it at the top and when the brakes wear it takes fluid from the reservoir to expand the caliper. Most people don't ever check their brake fluid for some reason so eventually the level drops low enough that it turns those lights on. If you don't know how to change brakes on an ABS controlled system I strongly recommend you just pay a reputable shop to do the work including replacing all the fluid. Otherwise you risk damaging the ABS controller.

The "grinding" sound you are hearing is almost definitely the ABS self-test. Every time the vehicle is turned ON and reaches 10mph for the first time it self-tests the system and actuates the ABS motor mounted on the ABS solenoid block, you will hear and feel it inside the vehicle because it's right on the other side of the firewall in front of the driver in LHD / US and Canada V35 cars. If any part of the self-check fails it disables all the systems and turns all those lights on.

Leave the VVT solenoids, they probably weren't bad to begin with but nothing wrong with putting on new ones.

O2 sensors, check them with a real-time OBD2 scanner and if the voltage is fluctuating properly then they're fine, again EXACTLY WHAT CODES.

Random misfires is probably a combination of all the other engine problems, particularly the cam phase sensors but you should pull and inspect ALL the spark plugs, if they have more than 50k on them or if you don't know when they were replaced last then put in new NGK PLFR5A-11 plugs. Inspect all the coil packs for any damage to the epoxy resin encapulation (black shiny part on top), any scorching of the spark plug well tube boot, any corrosion or damage to the contact spring INSIDE the well tube boot, and don't be shocked if you end up finding a bunch of oil down inside the well tubes.

A common cause of random misfires is the valve cover spark plug well tube seals failing and leaking oil down into the spark plug well. Eventually it reaches the top of the plug and contaminates the contact point which causes the plugs to randomly misfire. There are a few ways to fix the tube seals. Buy new valve covers, drill out the existing seals in the valve covers are replace with aftermarket, put Permatex Ultra Grey sealant on the existing tube seals and reinstall the VC's and hope it seals up enough to stop leaking.

I have no clue why your radio is blinking, that's not part of the engine controls. Disconnect both sides of each battery cable, hit the contact points on the cable and termination good with a wire brush, apply a thin layer of electrical anti-oxidation grease to the connection point and reassemble. There are 3 contact points on the positive wire, battery, fusible link (both sides of it) and the starter wire. If the radio is malfunctioning I think you have an electrical problem. Negative wire connects to the chassis right next to the battery, then from the front right side of the timing chain cover it goes beneath the coolant reservoir.

All these things are easy to fix fortunately except for that knock sensor harness but you already know that if you replaced the knock sensor. Gotta take off the upper/lower plenum, the lower intake, THEN you can get to the sub-harness and knock sensor.

Be sure to to the system recalibrations for throttle closed position, idle air volume, and an ECM reset when you're done with everything.

And post the EXACT codes you are pulling from the car.

https://www.nicoclub.com/archives/g3...procedure.html

 

VDC, SLIP and ABS has to do with the wheel speed and steering angle sensor. Replace the clock wheel spring and follow the directions on how to align the clock wheel spring when putting the steering wheel back on. I scored a clock wheel spring today for my car at the LKQ junkyard for 6 bucks. The only issue was, it was the wrong a year off.

If it is misfiring do a tune-up on it.

 

I have a 2006 G35 sedan and so far I changed the catalytic converters,A/T FR/B solenoid,Transmission Temperature sensor, fresh transmission fluid and filter, MAF , APPS ( whole assembly changed), new battery, and new brake pads, plus fresh oil change and filter.

My car symptoms are slip & vdc lights are on at the same time as the check engine light, late gear shifts, hesitant to accelerate from complete stop, RPMs are hesitant when pedal is fully depressed (very sluggish rev ups), reduced power, delayed response when stepping on gas pedal, the RPMs struggles to get to 2000RPMs.

Ive done the idle relearn procedure many times but it's not sticking. Im lost , HELP!

CODES: P0710 & C1131 !

also received a P0507, P2101, P2128, P2138, P0223, P0123, P0710 , but all parts was replaced as of today Monday, July 25. 2022.

 

Consider changing the ecu?

 

That does sound like an ECM gone crazy or bad. Have you tried just resetting the ECU first? Otherwise I would definitely look at a replacement.

here's the reset procedure:

 

P0123 - Throttle position sensor 2 (integral to the throttle body) excessively high voltage . This can be a problem with either the throttle body OR THE GAS PEDAL, the pedal is actually just two electrical switches.

P0223 - Throttle position sensor 1 (integral to the throttle body) sensor excessively high voltage. This can be a problem with either the throttle body OR THE GAS PEDAL, the pedal is actually just two electrical switches.

P0507 - Idle control system higher than normal. Probably caused by the actual problem.

P0710 - ATF temp sensor, there's two, this code can be for either of them.

P2101 - Electronic throttle control (throttle body) malfunctioning.

P2128 - Accelerator Pedal Position (gas pedal) switch 2 high voltage.

Pretty sure your gas pedal switch is bad which is throwing all the data for the throttle body off, replace it first and if it doesn't fix the issue then I suspect your throttle body is bad, make sure to replace the throttle body with an OEM Nissan or Hitachi unit, don't use aftermarket brands. Hitachi was the OEM manufacturer for that part.

You probably also have a failed ATF temp sensor but I would work on that later.