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Thanks. I reinstalled the condenser ignition coil this morning. Went for some test driving... and P0300 is still there. I set up a diagnostic appointment online with the Nissan dealer that I bought the part from this morning. Hopefully they'll run a diagnostic with my mods and provide me with a strong answer. With all of the electronic parts being new, I'm starting to worry that it's a mechanical problem. I also just notice my fuel pressure is sitting a little high at 54 psi. FSM says it should be approximately 51 psi. I don't know what the tolerance of "approximate" pressure is. I've included some info from my scan tool and app below.
One thing that stands out to me is that Bank 1 fuel trims are a bit higher than Bank 2. Like one has +9% while the other side has -4%. Have you had the injectors cleaned yet and flow tested?
The spray shape was similar to two jets spraying out for each of the twelve injectors (I have two sets, one that was already on the car and another set I removed from a sedan at LKQ).
Just got back from Nissan. They will not touch my car because: Z1 stuff (Plenum Spacer, Fuel Pressure Gauge) and Hitachi Coil Packs. They then quoted me $1,000+ to replace the coil packs because they are not Nissan OEM, WTF!!!! My OEM coils should be still good (showed similar resistance to the Hitachi ones... didn't spark test them, I need someone to crank the engine... can't do that alone). Should I put everything under the hood back to stock and take it back?
I would recommend taking it to a Nissan Z specialist shop in your area vs a dealership at this point. Nothing you have installed should stop a competent tech from diagnosing your issue.
The only places I know are in MD and in SC, so maybe too far for you.
Just scrolled back in this thread and noticed I had pointed out the trim differences between the 2 banks earlier. I know the 6MT revup engines have a different injector part number from the nonRevup engines. No clear info on what the flow rates are, but I would make sure whatever is in your car all match. If they do all match right now, then I'd mail them out to DeatschWerks to have them dynamic cleaned and flow tested. The fact that your two banks are so far apart seems to indicate a fueling issue. But then again every time you look at your car you find another thing busted, so who knows, lol.
I ended up uninstalling the plenum spacer, fuel pressure gauge, and reinstalled the OEM coil packs. The car actually drives a bit better. The acceleration response is faster, but still hesitant. Still getting P0300, P0304... P0113 popped up for a second, but now it's gone.
I'm in NC... SC border is about 10 minutes from me.
There's Soho motorsports about 6 miles away from me. I took it to them 5 weeks ago and they told me the P0300 was due to low oil pressure (gallery gaskets). I replaced the blown gallery gasket and it didn't solve P0300. I tried to schedule another diagnostic over the phone with them and they told me my cam sprockets are probably damaged/worn from driving with low oil pressure for so long. Soooo... were they trying to tell me to replace my cam sprockets? If so, all four... or just intake... or exhaust? Because purchasing all four sprockets would cost about the same as a used VQ35DE REVUP. Just the exhaust cam sprockets alone are $1600+ for both.
I made sure to use all the same fuel injectors a couple of days ago. Prior I must have used three of each. True, my car shows a new problem everyday, lol. Whatever is causing the P0300 has got to be either a mechanical issue or ECM issue at this point.
I found a wrecked 2006 6MT 350z RevUp on Ebay that was parting out its cam sprockets. It wrecked at 158k miles. The engine is disassembled and the sellers says he'll sell all four sprockets to me for $250. Will these cam sprockets work in my RevUp? If so, should I get them? If not, any tips on how to obtain some used RevUp cam sprockets... I don't have the money to pay for new ones.
Reasons why I believe it's the cam sprockets.
I've checked and replaced everything except cam sprocket, camshaft related parts in regards to P0300.
Can hear slight ticking noise from cam sprocket covers at idle.
Loud clicking noise when turning off vehicle.
Low oil pressure is what controls the VVT cam phaser functionality... I have no idea of how long the gallery gaskets were blown, it could be up to 3-4 years of driving with low oil pressure.
The 350Z didn't get the HR engine until 2007 so yes a 2006 has the rev-up. It's exactly the same rev-up that came in the 2005-2007 6MT G35. Have them send you a picture of the cam actuator cover it's UNMISTAKABLY different on the rev-up engine compared to either the regular DE or the HR motor.
$250 for the cam sprockets is a hell of a deal, I'd get it even though I do strongly doubt that's the problem. Sometimes you just have to trust that a reputable shop like Soho knows what they're talking about though...
However, the intake actuator sprocket can crack, I've seen pictures here, I suppose yes it could be due to low oiling pressure from a leaking galley gasket but I strongly doubt it. There is a return spring that keeps it in the normally retarded position and the oil pressure just forces it to push against the spring and advance, if there was low/no oil pressure it would merely stay in the normally retarded position. I'm VERY doubtful that this alone would cause damage to it.
Before you go any further on the engine though I think you need to do a compression test, it's possible something is smoked in one of the cylinders and it's a cheap easy test to verify that you don't have larger issues and thus not worth throwing more parts into this long block.
If you don't want to compression test then at least pull the fuel pump relay and crank the engine and just LISTEN to it while it's cranking for like 5-8 seconds, it should be perfectly rythmic, ra ra ra ra ra ra ra ra ra ra ra. If it sounds like it's got an irregularity to the individual cylinder compression as the starter is fighting against it like ra ra ra ruh ra ra ra ruh ra ra ra ruh then you DEFINITELY need to do a compression/leakdown test. If you can hear it then you definitely have something amiss.
If you do go down the line of cam sprockets and phasers, just know that the exhaust phaser and cover are a married set, so you have to get both together. The intake phasers are oil pressure driven, the exhaust ones on the revup engine are electromagnetic driven.
Thanks for the feed back guys.
Cleric: I did a compression test a couple of weeks ago. Here are the results. I will do another compression test when I start the process of removing the timing cover again.
Cylinder 1: 165 psi
Cylinder 2: 157.5 psi
Cylinder 3: 165 psi
Cylinder 4: 165 psi
Cylinder 5: 157.5 psi
Cylinder 6: 165 psi
When cranking the engine with fuel pump fuse removed, nothing sounds abnormal. Sounds like a healthy engine trying to crank without fuel (obviously). The ebay seller is sending me both pass/driver VVT covers, both intake sprockets, both exhaust sprockets, and the cam chains for $250. He sent a ton of pictures and they are identical to what's on my car now. I bought them... seller is about and hour away, so I should get them relatively fast.
I spoke with Soho again this morning. We had a good 15 minutes conversation. I told him, if my gallery gasket was blown, it's a good chance it's been that way for a while (years) and probably due to me not checking my oil levels properly over the years (I've been in mech engineering school for the past 7 years full time and studying has led me to neglect my car and house until either start screaming to be fixed). He went to explained that prolong driving with low oil pressure combined with low oil levels can demolish mechanical parts of the engine... especially VVT components. Said to replace the covers, and all sprockets... they would do it for $1400... he also suggested to buy used if I could, due to cost. He explained he's seen this combination part failure between "low oil pressure and worn/damaged sprockets" occurrence happen many times before on G's as they don't have oil pressure gauges, owners typically don't know their pressure is low and drive for years. I trust their experience. I plan on making the swap next weekend. I'm taking my time to order gaskets (3rd time opening the VC... definitely swapping the gasket this time), and o-rings so I'm not waiting.
Lost: I tried to find the number to UMR in Greenville, but I could not find it online, and I don't have a Facebook account. After looking through some of their pictures, I saw they actually do some cooperative work with Soho. The seller is giving the all the components needed for that swap. Regarding your feedback on the pressure/magnetic driven and Clerics feedback on wear damage. I completely agree with both of you. I cannot see how low oil pressure would cause wear/damage on the intake sprocket. I didn't see any cracks or tooth damage last time. I'll make video inspection of the old ones coming out and the new ones going in. I saw a video of a 4 cylinder engine with a failed VVT phaser showing what the camshafts are doing (below). The chatter he describes in his description is what I experience when I shut the car off and sometimes when I start it up.
Holy shii, thanks for posting that video I had no idea there was that much slap on the camshafts when the phaser was low on oil. I didn't realize there was that much play when it was just on the spring.
That makes perfect sense to me now how they crack, if you've ever seen a cracked one you would definitely understand it too.
Biggest issue with the stock oil pressure sending unit is it doesn't even turn the idiot light on until you're below 3 psi of oil pressure. An aftermarket oil pressure gauge, fuel pressure gauge, and voltmeter would be really handy on this car. But it's got to be that matching orange color like the rest of the dash, and dimmable
Haha. I make sure my aftermarket head unit is only displaying orange lights. I was thinking of making my own Volt and Oil pressure gauge using a microprocessor like Arduino and a OLED display.
Here, in fact after re-reading this post this guy ALSO had the P0300 code. Keep in mind he has the HR engine but changing out the phaser did NOT fix his P0300. Posted some good pictures though.
Damn, that damage was hidden. To be honest, I thought the intake sprocket was internally fixed with non-moving parts. Him replacing his sprockets and not solving his p0300 is disheartening. I hope the differences between DE and HR and the way I've neglected my car all add up to the sprockets fixing my issues or shining light on the main component causing P0300. If it's the latter I hope it's a Non-RevUP part. My next strong post will probably be in two weeks. I plan to make a 5 - 10 minute video explaining what I'm trying to resolve, what I've done up to this point, and my process. I'll film myself:
Opening up my old EXH and INT sprockets to see if there is any damage
Installing used sprockets
Timing chain installation procedure
I have to defend my thesis in 6 weeks and I still have about 60 pages of writing to go. So I'm using the repair next weekend as a break from my thesis writing and the following weekend I'll edit the video. I received those used sprockets within 12 hours of ordering from eBay. I know the seller is only 1.5 hours away, but that's still pretty damn fast. It's taking all of my will power not to go in the garage and clean them up. Even though it's not working the way I want, I love working on cars (or machines)... they are like giant LEGOs.
