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Anyone feel like schooling a newb mechanic

Trouble with removing the Exhaust Manifold...
Could anyone provide a newb mechanic with a tip on how to get this little bugger out (that damn angled 10mm screw)...

I just bought a socket set, but my 10mm wrench is pretty short so I am thinking that may be complicating the issue...



Btw, pic is looking down on the heat shield of the exhaust manifold.. kinda zoomed in...

Cheers,

-BTW, GREAT! concluding distinction between the first n second o2 sensors... I'll put the first in my new obx header and disconnect the second and live with the light...
 

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2.0 Sentra Lover
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why are you taking the heatshield off? i pulled my sr20s without removing the shield
 

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Trouble with removing the Exhaust Manifold...
Could anyone provide a newb mechanic with a tip on how to get this little bugger out (that damn angled 10mm screw)...

I just bought a socket set, but my 10mm wrench is pretty short so I am thinking that may be complicating the issue...
i'm not sure which screw you're talking about. The only one i see in the pic doesn't look angled... or hard to get out for that matter. Anyway, you should try a 10mm open end wrench if you can. If you don't have one, get one. You will need it VERY often if you continue to work on your car!
 

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i'm not sure which screw you're talking about. The only one i see in the pic doesn't look angled... or hard to get out for that matter. Anyway, you should try a 10mm open end wrench if you can. If you don't have one, get one. You will need it VERY often if you continue to work on your car!
For some reason i had a heck of a time getting it out.. in fact, that sucker is seemingly stripped and remains attached to the Ex manifold.. PS - I was using a 10mm wrench/spanner.. it is starting to become obvious to me, the common denominator of all my troubles installing the header...
 

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smog in cali is overated, theres plenty of places you can pay a "little extra" and pass. just dont get pulled over by the chp,then youll have their version of an inspection!!!:D
 

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Can someone explain to me how this mechanically happens? Is it specific to the timing of the valves of the QR25DE? After speaking to some mechanically inclined people and an actual mechanic, they don't see how this is physically possible.

These substrate pieces get sucked back into the cylinder and damage the cylinder walls, ultimately causing increased oil consumption.
Based on the timing as shown in this animation, I don't see how any back pressure could build up let alone allow the substrate to penetrate past the closed valve.

Just trying to understand as this could be the problem that's causing my car to act the way it is right now based on the description, but seems unlikely. A head gasket is the alternative.

Indicators:
1. 2qts low after 1300 miles from last service (oil and filter)
2. Dark colored coolant resevoir
3. Wet and dirty exhaust gases, but no 'smoke' that I can see

I've changed the following parts in diagnosing this:

1. battery
2. Cam and Crank position sensors
3. MAF
4. alternator

The battery and alternator were just general replacement, the car has 122,000 miles on it.
 

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IIRC it has something to do with the EGR-less design and the exhaust valves remaining open later.
 

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IIRC it has something to do with the EGR-less design and the exhaust valves remaining open later.
I had the car towed through AAA to a mechanic at home. Car had been sitting at my office since friday the 12th as I determined what I was going to do.
 

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I had the car towed through AAA to a mechanic at home. Car had been sitting at my office since friday the 12th as I determined what I was going to do.
Not many choices other than installing a new engine. Sorry....
 

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Unfortunatly, i live in california...
I was looking into getting a nismo header with cat., and crossing my fingers that it'll solve the problem.
anyone know anything about my problem in this situation?
Any help is good. ANY. Thanks!
 

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Unfortunatly, i live in california...
I was looking into getting a nismo header with cat., and crossing my fingers that it'll solve the problem.
anyone know anything about my problem in this situation?
Any help is good. ANY. Thanks!
The NISMO w/ header cat has been prone to cat failure and it is NOT CARB compliant, anyways.
 

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precat failure here. at 120k miles.

what happened is the ses light came on, so i got the cat failure code. went to a muffler shop,

the guy stabbed the kitten into a million pieces, and removed the other cat, the one under the car.

and after taking the kitten and the cat out he welded in one new cat into the middle of where the kitten and the old cat used to be.

in other words, i'm running on one cat.

1st question, anyone did that?

2nd question, there was this weird rasping sound when i engage it to a gear, no rasping sound when i rev it in neutral, only when i rev it in a gear. i asked the muffler dude, he said its normal because i deleted a cat. comments?
 

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OGT in 92 from the 1st EP
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Bummer. Hope your motor doesn't burn too much oil.

I run one cat in the same spot you are talking about, a cheap high flow I got off ebay, but it keeps the ses light off. And you will get some rasp with only one cat if the rest of your exhaust is stock.
 

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^^^
I have the Nismo header & cat-back. Same cat setup on my midpipe. No rasp, just bass and growl ; ) Every now and again I get the popcorn, but us 02's run hella rich so no surprise there. Man, I gotta get that back on the car. Had to swap it off to pass smog and haven't gotten around to putting it back on.
 

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the muffler dude told me that the cops can 1. check what you have under your hood, 2. sniff your exhaust with this... sniffing machine.

so if its illegal, they can tow your car away right there.
 

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Scarborough Nissan gave me a new engine!

I figured I'd share my story since there's so much bad history with the QR25DE engine.

I bought my '03 SpecV used in 2007. I read all the horror stories about this engine after I bought the baby! However, I didn't think it would happen to me because I couldn't feel any problems with it. It wasn't until recently I brought it in for CAA check up and the mechanic noticed I brought it in with low engine oil. He topped it up for me and said to keep an eye on your engine oil level.

At the same time, it was time for emission test so I brought it to Scarborough Nissan to do the test and told the service consultant that my car maybe burning oil. He said "Ok, we'll take a reading and we'll monitor it". So every 500km I would bring it back to Nissan for them to record the oil level. It wasn't until after 2000km of driving it (since the oil change by the CAA mechanic) that Scarborough Nissan said it is burning oil. I also informed the service consultant at Scarborough Nissan about the bad history of this engine and about the pre-cat problem. He told me good thing I brought it in before I hit 130 000km because the pre-cat is apparently covered under warranty upto 130 000km (I was at 128 xxx km when I first brought it to Scarborough Nissan dealer for the emission test). Because the pre-cat damaged the engine, they were nice enough to replace the pre-cat and my QR25DE engine. It took them about 3 days to give me an engine swap.

There's a plaque on the engine block that said it was manufactured 2009. At first I thought, I thought I might have gotten the ones that went into 2007+ sentra specVs but I doubt that it was the case. Prior to the ordering of the engine, the service consultant said that they will be just ordering the same 185hp specV engine that I originally have. As well, I reading some other forums and apparently Nissan have remanufactured QR25DE still in production (up to 10 years). The new part # for this bare engine block is 10102-8J0HARE.

In the end, it cost me nothing and I get comes with 1yr or 20 000km warranty on the engine block.
 

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Scarborough Nissan gave me a new engine!

I also want to add, from my experience with other Nissan dealers I've dealt with, Scarborough Nissan actual "DO" want to help their customers. They are at Birchmount and Eglinton (for those of you who live in Toronto).
 

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Precat failure here in my 02 is the QR25DE from the nissan altima the same motor ? What years are interchangeable ? Junkyard hunting for me I guess :(
 
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