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Current 5th gen owner. Bought a 5.5gen. Questions about radio/cats/o2 sims/brakes
So our VW is going back as part of the dieselgate nonsense. After loan is paid off, we pocket ~$14k. Already bought an 02 i35 w/ 78k miles for $6500. One owner. Really clean. Pics will be posted later in this thread. Came out of southern PA and has nearly no rust except on the control arms (minor), exhaust (always a trouble spot), and a little on the oil pan lip and oil cooler lines. A very light bit of that white speckling on the aluminum intake and timing chain cover.
Already did coolant flush, power steering flush, tranny pan drop and fill. Screen was clean. Just reinstalled it. New NGK Iridium spark plugs.
Pulled the coil on cylinder ??#6?? (rear right) and it was drenched in oil. Replaced rear valve cover assembly. Moved that coil to cylinder #1 just in case it fails, it's easier to get to.
Noticed light oil residue on the intake gasket. It looks like the PCV feeds oil into the lower section of the intake and it has lightly discolored the lower bank of the intake runners. Those runners lead to the front cylinder bank, so the front bank has been slowly fed oil for most of its life.
From the small dealer I got it from, the oil was absurdly overfilled. Like just over a full quart. Fairly clean, but I'm changing it very soon regardless because of the next statement.
Seafoamed it. Actually it was Chemtool B12. Through the intake line right behind the throttle body. 1/4 bottle or so. After getting it back to temp and doing a few WOT pulls, I ran about 2 cups of hot water very slowly through the same vacuum line. This made no difference in the mild rough idle I talk about next. (This is why I'm going to change the oil soon. Carbon breakdown and some possible blowby of water into crankcase.)
Before I get into the other questions, the car has a minor stumble at idle. drives 100% fine, but at a stop, I can feel the car shuddering ever so slightly. I am going to replace the coils since one of them was soaked in oil due to bad tube seals, but it's just not as buttery-smooth as the VQ30. At idle and in gear, if it wasn't for the exhaust, I'd barely be able to tell it was running. If the above-mentioned oil-soaked coil is mildly intermittent, is there a risk of that cat being damaged back there?
This is the best video I can find that is somewhat similar to the feeling I feel in the car. Obviously, no leaks, but I can FEEL that random stumble. Go to 3:51
Anyways, I've got some questions about the car, its quirks, and the possible fixes
1) Radio
The sound quality BLOWS compared to our stock 2000. It's very muffled and bass-heavy. Not in a clear way, either. Is this a known change from 5th gen to 5.5? I'm going to swap out the tweeters for more efficient ones to add some highs, but it's a huge difference! The 2000 is very well-balanced and the 02 is just BLEH
What's the ohm load on the factory amp? What can I replace without having to replace the head unit?
2&3) Cats and o2 sensors
So everyone speculates that the precat failure can lead to oil consumption and possible failure of the engine. After this next oil change, I'm going to start logging oil levels at every gas refill.
Where can we still get headers for this car? The parts sticky only lists the one link that is 404'd. Ebay leads nowhere. No amazon links.
Is there a way to punch out the pre-cats semi-easily?
Never really read into o2 sensors, but if I put headers on, I'll need them. Where do we find them and how do I install them?
Thx
4) Brakes
The dealership changed the rotors but I think reused the old pads that had a good bit of life left to them. Obviously, they didn't seat correctly and they're scraping when I turn the wheels. Also, they're very firm compared to our 2000 and feel like crap. We've put about 500 miles on them to see if they would break in and they still feel crappy. What's a good company to look for replacement rotors/pads? If I'm in there, I might as well upgrade to some slotted rotors or something. What sucks is that I had a set of 02 Stillen rotors I picked up at a swap for $50!! I intended to just upgrade my calipers to use them but never got around to it and resold them a few years back.
Age-old question. The inside of this engine looks just like the outside. No yellowing or discoloration. The inside of our 2000 with 170k miles is the usual gold-ish color.
What is the definitive answer on engine longevity for dino vs synthetic? We live in FL, and we see operating temps below 50 degrees maybe 10 days out of the year. So 10-30 or 5-30 is still the recommendation?
PS If anyone lives in the Ocala,FL area and has years of experience with a 5.5gen, I'd love to buy you lunch and discuss things like this and have you look over the car. (no h0m0, I'm married lol)
I can meet as far as Gainesville, Orlando, or Tampa area.
Last edited by mydecember1985; 12-31-2016 at 12:15 AM.
Wait, am I reading around the web correctly that the cat is warrantied for 80k miles? Any damage resultant from a failed precat is covered by Nissan? So should I drop the front precat and see if its clogged? I'm at 79,200mi right now
It's dark out now, but is there enough room to send a borescope through the upstream o2 sensor in the front bank to see if the top is clearly clogging?
Last edited by mydecember1985; 12-30-2016 at 11:50 PM.
A few quick answers since I'm about to walk out the door.
Removing the cat for inspection can be a can of worms. If the car has any rust the studs may be ready to break. The rear one is a tough spot to drill out broken studs just for an inspection. I like the bore scope idea much better. Especially on the front.
Different parts of the car are covered by federally mandated warranty. The cats do have an extended warranty but I don't know if there's a time period that goes with it or how they define "failure".
There are headers for the car. The headers will have a bung for the primary o2 sensors. The secondary o2 sensors are only there to throw a code if the precats fail. There are ways to compensate for that though.
Always do an oil change after upper intake cleaner.
I'm a big believer in synthetic oil with extended intervals.
I'll pop into the thread later too.
If you're ever in the Panhandle area send me a PM.
For the idle stumble: Clean the MAF, run a bottle of Techron cleaner, fill up with Top Tier 93 gas and see if that helps.
Radio: Yeah, it sucks. Rap radio stations sound like muffled garbage mixed in with a comically high level of bass.
Brakes: Akebono pads FTW. Have heard good things about Centric prem rotors.
Oil: The VQ35 beats up / burns oil. Because of that, many people just run dino. I use syn b/c I stock up during rebates and it ends up being cheaper than dino. I like the peace of mind of added detergency and better base stocks. I don't drive my I35 much so I do 8-9 month / 7K mile OCIs.
A few quick answers since I'm about to walk out the door.
Removing the cat for inspection can be a can of worms. If the car has any rust the studs may be ready to break. The rear one is a tough spot to drill out broken studs just for an inspection. I like the bore scope idea much better. Especially on the front.
Different parts of the car are covered by federally mandated warranty. The cats do have an extended warranty but I don't know if there's a time period that goes with it or how they define "failure".
There are headers for the car. The headers will have a bung for the primary o2 sensors. The secondary o2 sensors are only there to throw a code if the precats fail. There are ways to compensate for that though.
Always do an oil change after upper intake cleaner.
I'm a big believer in synthetic oil with extended intervals.
I'll pop into the thread later too.
If you're ever in the Panhandle area send me a PM.
The front actually doesn't look that difficult to get off. Yeah, the exhaust system is rusty, but for a northern car, it's in great shape. I just ordered the borescope and o2 sensor wrench so they'll be here next week. If I can't see well with it, I'll just have to pull the front precat. Maybe if I break a stud, it'll force me into going ahead and buying headers.
I just really want to catch this before it causes any damage. I'll change the oil on Monday and start tracking consumption, but I've only got an 800-mile window before I run out of the warranty (if it still applies to an old car)
By all means, please provide a link for the headers or some high-flow cats if those are acceptable to avoid future issues.
Honestly, the car isn't even registered yet. I have insurance on it, but it's technically the wife's car, and getting her and the kid all the way across the county to the tax collector's office is a logistics nightmare. We kinda run opposite schedules.
Originally Posted by mclasser
For the idle stumble: Clean the MAF, run a bottle of Techron cleaner, fill up with Top Tier 93 gas and see if that helps.
Radio: Yeah, it sucks. Rap radio stations sound like muffled garbage mixed in with a comically high level of bass.
Brakes: Akebono pads FTW. Have heard good things about Centric prem rotors.
Oil: The VQ35 beats up / burns oil. Because of that, many people just run dino. I use syn b/c I stock up during rebates and it ends up being cheaper than dino. I like the peace of mind of added detergency and better base stocks. I don't drive my I35 much so I do 8-9 month / 7K mile OCIs.
I have a bottle of cleaner in it now with regular gas. Next tank, I'll try premium. I'll have to pick up some MAF cleaner. Apparently I'm out. I never had MAF give minor issues with the 3.0. It was either fine or 100% failure.
I'll have to decide on the oil thing after I see how much it consumes. If it chews up 1qt/1500 miles, a 7500 OCI would cost me a full extra oil change of synthetic. If it does eat oil, I'll have to consider the cost to keep it topped off. Dino oil actually may end up being cheaper in the long run even with the shorter OCI.
Has anyone looked to see if the rear deck amp is the same on the gen 5 versus 5.5? I havent and I'm about to leave for work. If so, is the weak point the speakers themselves or the actual head unit? If the speakers, I'd be perfectly happy pulling speakers out of a junkyard i30 and slapping them in the i35. If the head unit... (;ﾟ︵ﾟ
Thanks for the insight so far. Here are pics of the intake and the oil discoloration of the lower plenum channels. When I shot throttle body cleaner through it, it came out pretty brown.
See pics for notes
This picture is actually to show the oil residue you can see on the intake gasket to the right. I was taking a picture of the oil I slung oil all over the valve cover from that back spark plug tube being full to the brim with oil.
Very clean internals.
Note the darkened plenum passages where the PCV feeds oil into the lower part of the manifold and front runners. Intake cleaner took it right off, but it came out rather dark and thick.
Intake runner leading to rear bank. I didn't think to take a pic of the front bank that should be of more concern since that's where all the oil is being delivered.
Last edited by mydecember1985; 12-31-2016 at 12:03 PM.
I have a 2000 maxima and a 2002 maxima, the sound sytems are NIGHT AND DAY to me. I started a thread a while back about it and came to the conclusion that it is indeed the head unit causing terrible treble and kinda flat EQ.
Seems like a nice low mileage car you got there, good thing you are doing all the important stuff before it kills the car haha.
Sent the borescope into the front cats and cylinders. Everything looks pretty normal to me, so I guess that super-mild stumble is just the difference in the engines and the motor mounts. It's just not as smooth.
Pics below.
left front cylinder
middle front cylinder
right front cylinder
zoomed out view of front pre-cat
a little closer
missing piece in the corner :'0
video of inside the cat here. Does it look normal to you guys?
THe reddishness is because the camera was overheating. The car had been run about 30 minutes before, but it was still hot inside the exhaust.
I think I'm gonna run to Tampa You-pull-it tomorrow. Their lot has been flooded with like 40 Maximas/I30s/I35s in the last month. I'm bound to find something I need.
Things I'm after:
Spare MAF for each car
Thick carpet trunk mat
axleback exhaust section
oil cooler return line
mirrors for I30 (paint is fading)
?????
Yes the precat is starting to break away, but that little bit isn't gonna cause any harm. I'd say you still have a good amount of time before anything bad happens. But just keep in mind that headers or gutting them are in your future.
I'm sure this gets asked too often, but what headers are out there? Just OBX nowadays? They used to be cheap, but it looks like they're nearly up to Cattman prices.
you are mechanically inclined, come time when u want to do any other exhaust maintence then gut the precats, you just need a good drilll, and 18" spade bit, and a way to hold the cats in place when your drilling.
they look fine to me and about where mine were at 187k when i gutted them. you can go for headers but they seem like more work at times... gutting or headers obvi need secondary O2 sims
yes leave the cat alone... and when you want to tinker w exhaust then revist it, unless the engine is still apart by the means u got these pictures then maybe go for it since your can of worm's lid of a project is already opened
12-30-2016, 11:15 PM
hot water 
The 2000 is very well-balanced and the 02 is just BLEH
