Hey guys,

I've been using the forum and all the tutorials for all maintenance and issues I've had with my G and its finally time to post so I can get personalized opinions lol. I have a 2004 g35 6mt coupe. It's going to be a long post thanks in advance I want to give you guys all the detail.

Background info: got my g back in August 2016 with about 80-90k miles. took it to my local Nissan dealer for a detailed inspection. they said mostly everything was fine but that my valve covers had a small leak and I would eventually have to replace them. Since I didn't have the money back then I only got my gaskets replaced and the car was fine for the next 2 years.

Summer 2018 I got cylinder 6 misfire, changed spark plug and ignition coil then it turned to random misfire so I replaced all the spark plugs(ngk iridium) and all ignition coils. Did all the throttle resets with the gas pedal and all was well after that. Around this time I think I would let my gas tank run too low quiet frequently so the gas gauge started acting up. It would read only up to 3/4 after I filled up and just randomly go down to empty knowing I had recently filled up. I ignored this since it caused no problem.

January 2019 on my way to work car went into limp move briefly but it corrected itself quickly. Ignored it and moved on.

About a month ago now, was driving home and car went into limp mode after driving for 2 minutes and then it stalled. I sat waiting for the tow for hours since the car didn't turn on and eventually after 3 hours car turned on and I drove it home on limp mode (tow never showed it was 2am, somebody actually keyed the trunk and stabbed one of my tires that same night. I thought they might have put something in the gas tank but last week i replaced the gas tank and the gasoline was clean).
The day after, assuming it was same issue as year before and because I did get the random misfire code, I replaced all spark plugs, car turned on but it was still idling weird(misfire) I performed idle relearn and car took a couple minutes to level out with the idles. Car ran fine for about two weeks. The spark plugs did have a little bit of oil on the tip (some of them not all) but it wasn't nearly as bad as back in 2018. I used NGK V-power spark plugs since they were cheaper and had good reviews, also I was fearing a more serious problem didn't want to waste the money on good plugs that would go bad again.

About 2 weeks ago now, at around 2am again, car started misfiring, limp mode, died on me and didn't turn back on. Had to buy AAA and got car towed back home. This time car did not turn back on, no CEL at all. Checked the plugs and coils everything seems ok. didn't want to just keep cycling new plugs every 2 weeks. I did notice for a while the car kind of struggling to speed up when I stepped on the gas kind of hard. What I mean is the car wouldn't speed up fast but rather kind of struggled, jerk a little, as if a lack of power or fuel.

I have now changed the passenger side camshaft sensor, crankshaft sensor fuel pump, replaced fuel pump, cleaned throttle body and MAF sensor and the car actually turns on but still misfiring or limp mode. If I step on the gas the revs actually drop and the engine stalls. If I let it be the engine revs up as high as 3,000 and down trying not to die. it was like this for about a week with no CEL light.

Before I changed the whole fuel pump assembly(I first only changed the actual pump only & reused strainer bag) a buddy of mine who's a mechanic for firestone took a look at it and said it seemed like it wasn't getting enough fuel. We took the air intake tubes off and sprayed throttle body cleaner in the throttle body and the revs would actually stay up and not stall when I hit the gas. Told me replace the whole assembly b/c maybe I had gotten a faulty one but nothing changed after I did.

My theories:
1. most obviously lingering problem, the valve cover nissan told me would need replacing 3 years ago. so I went ahead and bought them and should have them by friday. Doing the job myself.
2. Crazy theory but let me know what yall think: because I ran the car on empty so many times (never actually died due to lack of gas) the pump sucked up dirt which then clogged my fuel injectors and this is what is causing that lack-of-power feeling, the random misfires and the idles dropping and engine dying when i hit the gas as well as fuel gauge not reading correctly.

Should I go ahead and replace the injectors while I'm doing the covers? should i change camshaft sensor for driver side too? ( I already bought the sensor just didn't want to put it in because I'm really not getting any codes... don't want to waste the $100 I might need towards the injectors).

Also the negative cable for the battery is getting a lot of that corrosion the white/blueish thing.. it is a new cable i replaced back in Winter since the old one stripped and wasn't tight enough. I do have to charge the battery with my other car or I just use my other cars battery sometimes since its been sitting for a couple weeks now.

Thank you all for your time I appreciate your input,
Nick

 

Replace your battery, that blueish corrosion is leaking hydrogen gas electrolyzing with the different metals it comes in contact with. You will need to thoroughly SCRUB those metal parts to get all that crap off, probably also have to use a pick or screwdriver and chip it off because it builds up pretty thick, use a wire brush once you get the big chunks off. Coat everything in a thin layer of electrical anti-oxidation grease when you reassemble it to the new battery.

Did you use Genuine Nissan or Hitachi sensors for the cam and crank sensors, I suspect all of your misfire issues are an intermittently bad sensor.

Remove the MAF and clean it thoroughly with MAF cleaner.

If you suspect a fuel delivery problem order the sandwich adapter from Z1 Motorsports so you can read the pressure, you can order it with a gauge so there's no need for another tester. I went with the fuel gauge AND the fuel port so I have a way to bleed off fuel pressure when working on the system.

https://www.z1motorsports.com/z1-pro...rt-p-9160.html

You could replace the injectors just for the sake of preventative maintenance but I really don't think that's your issue, start with the battery, replace any cam/crank sensors that aren't Genuine Nissan or Hitachi, clean up the REST of the electrical system (bonding jumper from timing cover to chassis below the coolant reservoir), clean MAF, perform all the resets again (make sure to follow the FSM directions when doing the idle air reset or you will completely F the whole algorithm).

 

There's a really good chance the whole problem is the battery, when you have an internal failure you end up with pretty wild electrical noise and voltage fluctuations, one cell overheats/overpressures and cracks the post connector then gas escapes and corrodes everything, Computers don't like all that screwed up voltage, ESPECIALLY when you have a computer that's trying to read sensitive FREQUENCIES sent by the cam/crank sensors.

EDIT: I used to have a 1990's chevy that would burn up the ignition control module about every 2-3 months, I probably went through a dozen of them before I realized it was all caused by the battery which was leaking gas and corroding the posts exactly like yours is.

 

Passanger side camshaft sensor is hitachi and the one i havent installed(driver side) is also. the crankshaft sensor however, is not. I will replace those and see what happens. Thank you. also will replace the battery even tho I replaced it maybe 8 months ago when I started having issues with the starter. as a side note, I did connect a different cars battery for a while and the car was still acting up. Not sure if it means anything.

I'm still going to go ahead and replace the valve covers today since they are leaking but I will hold off on the injectors. Will update later tonight with good news hopefully

 

Forgot to mention, cylinder 4 wiring harness has the wire a little bit exposed since i accidentally scrapped it when I did the spark plugs a couple weeks ago. I put electrical tape all around it a couple times and no wire is exposed. The car was running fine like this for those 2 weeks, could this also be the cause of the problem??

would HATE to have to buy and change a new wiring harness

 

You don't need to replace the harness, just cut the wire, strip it back a little, and use a solder seal connector to repair it.

I really don't recommend using a lighter for those things though, too easy to scorch the insulation, use an actual heat gun.

This is what a solder seal splice looks like if you aren't familliar, they're easier for most folks to use than traditional solder + shrink tube since it doesn't require a soldering iron. It's a permanent fix for broken wires, electrical tape is not.

 

Awesome thanks. Was doing the valve cover replacement yesterday and of course one of the valve cover bolts snapped on me upon re installation. This crap always happens. Now I have to wait until Tuesday from OEM bolts from my local Nissan dealer. Can you recommend any aftermarket bolts that will work? I tried looking but no luck.

 

I recommend an inch/lb torque wrench and following the torque directions in the FSM

 

update on my G:

• finished valve cover replacement, removed broken bolt, all went well.
• installed new OEM VVT solenoids (both) from z1motorsports
• installed bank 2 Hitachi camshaft sensor.
• Put in a new battery.
• got a new negative battery cable.
• new plenum gaskets since the black cover on the old ones was flaking off.
• installed 6 new NGK double platinum spark plugs.
• removed catch can and connected PCV valve straight to intake.

What I've done before:

• new fuel pump.
• recent oil/filter change.
• cleaned MAF sensor and throttle body.
• new hitachi bank 1 camshaft sensor.
• new duralast ( i think) crankshaft sensor.

The car turns on but again sounds like a lawn mower very rough idle. this time it stayed on longer until the rpms eventually dropped to 0 and the engine stalled.
I performed all the idle resets and such. Any ideas??

Maybe throttle body as it is not opening when i hit the gas with the ignition switch on?
maybe fuel dampener? i heard it causes similar issues with the exception that I do not hear a ticking noise.
FUEL Injectors? I really hope its not them. getting to them is easy now but just time consuming.

Im posting a link to show how my throttle body moves when i turn ignition on for 2 secs then off 10. it does not move at all with ignition on and me hitting the gas. https://drive.google.com/open?id=1aL...n7rXUCxyZhxFRs

this one is how rusty my negative cable was because of my old battery. https://drive.google.com/open?id=1iG...T8UvhbP4Rv8k1r

there is no CEL or pending codes or anything any input is welcome I gotta get her running ASAP its been too long... Maybe I'll give up and tow her to my local Nissan dealer every though I don't trust them at all.

 

Yeah my TB on my 2006 doesn't move either with ignition on and the pedal on the floor.

Next I would replace the Duracrap CKP sensor, fuel damper causes issue but not like what you're experiencing.

Plug in an OBD2 scanner and watch upstream O2 sensor data to see what it's doing on startup.

I'm starting to suspect maybe your timing chain jumped a tooth.

 

Okay I’ll replace that sensor.

Not familiar with reading those readings but I’ll do some googling and figure it out.

Also, last night the car was starting and idling extremely rough but it did turn on. This morning it wouldn’t turn on again as if the battery was dead. It’s pouring rn so will try again tomorrow. Thank you for the help!

I’m going to record a couple clips maybe the noise and everything will help understand better.

 

You know a couple weeks before the car died I would hear a whining noise coming from Under the hood. Could it be that the alternator went bad and thats why its eating up all the batteries? And this the car not getting a steady current and causing all the other issues?

I’m gonna be both mad and relieved if its just the alternator but damn I been had it sitting for WEEKS for a simple alternator

 

If you're charging the battery to full then I doubt it's the issue. With all your accessory power off you can drive a car for about an hour with no alternator output.

I would take the belts off and spin everything by hand to see what the whining sound was.

 

Update on my G. Took it to the mechanic he checked wiring, timing, fuel pump, everything was fine but he says the injectors and not receiving ground.

Basically he said either my key is bad which is activating the immobilizer and needs to be replaced or the ecu is bad and needs to be replaced.

He thinks its more the ecu because all the information and wiring going to the ecu is good but nothing is coming out of it( something like that). I know the ecu sends ground to the injectors to make them spray so it makes sense.

Now I can take it to the dealer and get robbed of $1,600 or try to find a used ecu on ebay and just take the car/key to be reprogrammed at dealer. Any suggestions on finding the ecu? Do the part numbers have to be an EXACT match? Im getting ready to call dealer with my vin # to get my original ecu’s part #.

on the side, I’ve been looking for cars and I’m considering a 2015 benz c300. 40k miles on it. Anyone have experience with these? I’ve read about a lot of issues with the wrist pin and just a lot of minor (yet expensive) repairs.

 

NATS/IVIS will prevent fuel/spark, is your security indicator light solid red when cranking?

Dealership diagnostics only cost about $125 and they can run the ECM test in Consult-II which will either confirm the suspicion or tell you what the problem is.