As the title states my 2003 vq35de has consumed 5 quarts of oil over roughly 1400 miles since my last change. I just hit 100k it has been consuming oil for awhile now just never at this rate it has always been manageable. The dealership used to change my oil since they offered me free changes until one time I didn't feel like driving the 40 mins away, decided to do it and only 2.5 quarts came out I know, shame on me for not checking the dipstick religiously, there was no signs of any trouble and it's always changed at 3k or earlier. This was around 70k and I asked the dealer to check it out and they said it was fine. Ever since I have been taking care of it myself as I said the consumption had been at a reasonable rate and the car is now out of the warranty period, bought at 52k with a 24k extended warranty. Thanks a lot Nissan, you really stuck it in my ***. I'm sure they knew about the issue and happily declined to bring it to my attention while I was in the extended warranty period but I have no way to prove it.

That being said I am moving on and starting to look for a solution. From the reading I have done on oil consumption, I have gathered so far that the cheapest way I can fix this is a rebuild which I am going to attempt to do myself (or as much as I can do) but this is my first attempt at a tear down and rebuild. I have started to price this out, (pricing from courtesy parts) so far I have:

Updated Parts List:
gasket kit - $265
piston ring set - $125
crankshaft bearing set - $40
connecting rod bearings - $9.32 x 12 each = $111.84 (Cosworth Set $125)
head bolt kit - $54
oil pump - $205.02
water pump - $99.83
Total: $913.85 (with Cosworth rod bearing set, I don't see a reason to get OEM with the price so similar)

Tools List:
engine hoist - Rental $26 day/ $107 weekly
engine stand - $53
3 piece Micrometer set (0 to 1", 1" to 2", and 2" to 3" / 0.001" increments) - $29.99
inside micrometer ~$400 O_O I will have to try and find one to borrow...
Total: $108.99 (without inside micrometer)

What else should I need? I have searched quite a bit on this topic but have been unable to find specific information. I am not opposed to an engine swap but I have a lot of worries about buying a used engine because I have no way to verify anything, whether it runs properly, doesn't consume oil, has the claimed 40k miles instead of 140k, ect. I appreciate your advice in advance, I am trying to be positive and look at this as a learning experience moving forward. Thanks for your time, -Mat

 

I think you need to find an engine builder. If you couldnt handle an oil change a motor rebuild will be too much for you.

 

Kudos for attempting a DIY fix. I have enough trouble with replacing a intake much less venture inside the motor.

Have you considered buying a reconditioned motor. One with a warranty?

 

^+1 to davidv.
Those prices sound a bit low, but you'll also need a few somewhat specialty tools - a torque wrench to start.
You'll need to have some machining work done, such as ridge reaming and cylinder honing.
All in all, I think the "cheapest" and certainly the quickest will be to buy a used engine.

 

Wow, thanks for dropping by with the worthless input. I still can't tell if this is a joke and you are taking a lame shot at me or you really just can't read. You had always seemed like an intelligent poster over the last few years I have been here, nice job blowing that. I think on line FIVE of many we established that I was capable of changing oil. But thanks anyways for your incredible reading comprehension skills If you don't have anything worthwhile to contribute gtfo. If I chose to let Nissan change my oil because it was free and I was under the false impression that they would actually take care of it properly so be it. I've done a lot of my own work on the z: clutch and flywheel replacement, suspension component replacement, coilover install, brake replacement, full exhaust install, interior gutting, various engine components, custom fiberglass system installation, etc just never gotten to rip into the VQ, but I am sure I am quite capable and am at least willing to try.

 

Thanks David, yes I have been shopping around, cheapest I have found was $1700 and I am just trying to consider all my options, as I am thinking a rebuild might end up being cheaper. The engine will be another $200 in shipping charges but comes with a full 1 year warranty. Not easier but cheaper, my time is not worth as much as my money haha. On another note it is funny you responded because that isn't the only thing I've been shopping for. If I happen to stumble upon a 2009 chicane yellow touring with sport package and < 10,000 miles and 100% clean not even a scratch, we just might become twins

Thanks Dave, a torque wrench I do have but yes I'll need to pick up some honing tools, and inner and outer micrometer to start. Those prices are straight off courtesyparts.com

 

It sounds like you're probably capable, but I thought of some more tools: engine hoist, engine stand... I suppose you can rent to some extent.
If it was me, I would only take it on if I was upgrading a bunch of the internals. I think you'll come out ahead by buying used if you want to stay with a stock engine.

 

+1 trust me. youre getting yourself into something you may not want to. you need new head bolts or studs. probly dont need to rebuild without checking out all the tensioners, waterpump, etc.

I just did this without even getting into the pistons and rings on an engine i thought would be usable and it left me ~$800 in the hole with nothing to show from it and a month of my time. I promise you wont get your stock engine back together as well as it came from the factory. at least not the first time and trust me, you will forget something.

it was a pain and i wish i would have never started. and i would never replace it with stock internals if i did it again.

 

Oil pump/Water pump should be added to the minimum list

 

Thats not fair to say, I was able to take mine apart and put everything back together just fine the first time. Just take your time, and be organized when your dismantling the motor. Its really not too bad.

 

it's an 03. it's not a rev up with bad rings. it's an 03.

 

I'll add those to the list, concerns noted as well, thanks again Dave

Eric - Couple things, What did you mean when you said I probably don't need to rebuild without checking out all the tensioners, waterpump, etc.? I can't imagine problems in this area is what is consuming a quart every 300 miles. And I hear you about losing a month of your time, but to be honest I'm going to have to agree with Redman... I'm pretty meticulous I don't see how I would ever just "forget" something. I will be following the Haynes manual down to a t, all hardware ziploc'd and labelled, I'm even contemplating video recording the tear down process for reference when rebuilding. I do appreciate the input it will be considered and I'll add head bolts/studs to the list.

Redman - Thanks for the vote of confidence bro

Thanks Glex, will be added to the list.

What is this even supposed to mean? No bad rings? Where the f is all that oil going then?

 

Updated the parts and tools lists if you guys could give it a look over I would appreciate it!

Keep the responses coming! Thanks all

 

Jumping to rings without doing a leakdown test is mistake IMO. All of that oil could be coming from your valve guide seals. This is discussed in many threads. I had a similar problem (burning 1 quart every 300-400 miles and it WASN'T my rings.

 

Thanks for the info, searching as we speak. I'll plan on doing a compression test very soon.

Edit:: Found this post:
in this thread:
https://my350z.com/forum/engine-and-...-question.html

Sig says he's an ASE master tech, nissan specialist... is there something to his post?

 

He's right. Leak down will tell you more than a compression test and you can pinpoint your problem.

 

So was the issue ever diagnosed? Was it fixed?

Also have an 03 with recent signs of burning..