cardana24

iTrader: (81)

I will be putting a 'new' upper intake manifold on my fourth gen. I was wondering if there are any tips you guys have for me while I am replacing it. I already have the old one loose and ready to come off. I know I should clean what I can while it is out, and I also have a new gasket, and I will replace that. Do I need to use some sort of sealent with the gasket? Any tips will be appreciated. Thanks.

-Carson

NmexMAX

iTrader: (22)

When we did my VI, no sealant was used for any of the gaskets, just a new ones all around.

If it's already loose, than you should have no problems if it is a direct replacement, if you were able to get that bolt in the way back, where the ex. manifold is, then you're good to just take it off.

What kind of "new" manifold are you putting on?

cardana24

iTrader: (81)

the new manifold that I am putting on is just another US manifold. But the one that I am putting on is polished and it has been ported out to 70mm to match up with my PF TB.

Zack342

iTrader: (89)

Plenum......

cardana24

iTrader: (81)

thanks for the advice, english teacher

cardana24

iTrader: (81)

update...I have it all off except for the hoses that come together on the fitting on the firewall side of the manifold, its right before the manifold makes the bend to the throttle body. The clamps are at an angle that I cannot get needle nose pliars on them...I am going to get the 'bent' needle nose today and try those. Does anyone have any advice on how to disconnect these two hoses?...they are a real pain. Also while I am in there I am going to remove the valve cover and put a new gasket in and paint the valve cover...any other advice while I am in there? Thanks.

-Carson

Nismo

iTrader: (18)

label the vacuume lines

Nismo

iTrader: (18)

just cut the hose off and buy a new one, maybe replace all the vacuume hoses while your at it.

cardana24

iTrader: (81)

I thought about that, and I have already replaced most of my vacuum hoses, but the thing is the hose on the back is very dense, I doubt my local advanced auto parts stocks something like that....oh well...I am going to go give it a try on my lunch break

DaThrillr

maybe chenge the egr gasket... and while u have the iacv out u might aswell clean it out... listen to nismo change out ur vacuum line the old ones might have worn out and ull prolly get them confused so label them.

also check the knock sensor its alot easier to change it when the top plenum it out

Broaner

iTrader: (10)

Definitely cut the hose. And when you put it back on you don't even need it. The coolant lines going to the TB and EGR area are useless except for cold idle. Just turn them around into themselves(Completely eliminate the sytem). I did it recently and no problems.

cardana24

iTrader: (81)

well I ended up getting the off yesterday....the manifold is pulled, and my valve cover is pulled and the paint is drying....I will be clearing the valve cover on my lunch break then putting everything back together when i get off....hopefullly everything will good smooth. Thanks for your advice

DaThrillr

there is a certain way to put the valve cover back on... did u follow those directions?

stephenlc

iTrader: (1)

the valve cover is just held on with some allen bolts. Does not matter.

When changing the inake manifold you probally want to change the throttlebody gasket and the egr gasket.

DaThrillr

i think ur confused
i dont know what cover he is talking about but, the coil cover is held on by allen bolts and the valve cover is held on with bolts and has a rubber gasket. the bolts need to be tightened in a certain order, or should be tightened in that order

cardana24

iTrader: (81)

ok I posted this in the boosted section, but what the hell do you do with the coolant lines that go to the A32 TB? THe pathfinder TB does not have hook ups for the coolant lines....do you just connect the coolant line from by the EGR to the one below the TB? Any help would be appreciated, I really need to get this done tomorrow.

Broaner

iTrader: (10)

None of those coolant lines are neccessary or benifit anything. Simply dead-end them or turn one line around onto the other of the same system.

cardana24

iTrader: (81)

I am not positive I know what you mean by turn them into eachother? THere is one that comes off by the EGR and goes thru the back of the manifold then into the thottle body....then the other one goes from below the TB to the bottom of the TB....I dont get how you can turn these into eachother? Thanks for your help, I am just not fully understanding what you are saying.

Broaner

iTrader: (10)

What I'm saying is that you should completely eliminate the intake cooling system. It actually heats up the TB. Follow the lines back to the point where they brake off the main coolant pipe. That point is next to the front valve cover. Take off one of the lines. Disconnect the end of the other line and bend it around so it forms a U when you connect it to the open spot. It may get kinked but it doesn't matter cause no coolant needs to flow through there any more. You get what I'm saying now? If you want I can take a pic. Basically you will only need seven inches of the stock hose going toward the TB to make this work. You'll save yourself a heated TB and a bit of excess coolant and weight. The EGR port spits hot exhaust into the IM so to get the most out of the engine you should disconnect that too. Thats for another thread though. Check here for that info.

Badaxxima

Oh Jesus, please tell me that you are not talking about a Throttle Body Coolant Bypass! We've been over this 5-Thousand times!

Cardana24- Do not listen to this kid. If you do what he is saying, you'll activate the fast-idle cam and your car will idle extremely high (1500-2000RPM). The cars idles high to raise oil/water temp. to operating range. When the coolant reaches a certain temperature, a sensor in the throttle body switches off and allows the car to idle normally. The air passing through the Throttle Body is only there for a few milliseconds, this mod won't cool down the air enough to even give you 1 horsepower.

Jason R

iTrader: (39)

Carson, you get that intake plenum on yet? Give me a call if you decide to come down to Richmond.

Broaner

iTrader: (10)

You are very mistaken sir. First, if you do what I'm saying you will de-activate the fast idle cam capability. This means that the car idles the same no matter how warm or cold it is. Mine idles at 750. On cold start up this does help it warm up a bit faster but at the expense of all that coolant running through there all the time. Go back to your Sentra . Here, we use mechanical fast idle "sensors". It is not a sensor at all. If it were a sensor would coolant even need to flow through the TB? I didn't think so. A sensor would do a fantastic job of controlling the "fast idle" if we had drive by wire TB's. But we don't so the link between the temp of the coolant and the butterfly valve must be mechanical. This is how it works. A mechanism is set in the TB. Coolant flows behind this mechanism and pushes out a plunger as it heats up. When the plunger is in(Cold coolant) the cam on the TB is positioned such that the butterfly valve is held open. When the mechanism pushes out the pluger the cam moves accordingly because it touches the plunger. The cam gradually goes to its normal(Warm) position in which the butterfly is completely closed at idle. Any other questions?

Aside from the technicalities, this change(Notice I didn't say mod) cleans up the engine bay of the rediculous amounts of hoses everywhere. It also, removes excess weight(Coolant and hose) and cools of the intake charge. BTW, you don't think heat transfers from the TB to the IM or Midpiping? Though it may seem miniscule to you, it does make a difference.

Cardana knows the true story. He posted this thread in which moderators and hlh0501 agreed that these lines are not necessary. http://forums.maxima.org/showthread....hlight=Coolant hlh0501, said and I quote, "Or just eliminate the EGR as well and don't mess with any of the coolant lines". If you don't believe him you've got problems.

Who's the kid know? Go back to school.

Ladzio

iTrader: (8)

See link in my sig. Maybe something there could be helpful. GL!

cardana24

iTrader: (81)

what I ended up doing was getting a piece of 5/16 fuel line and hooking the line from by the EGR to the the line in front of/below the TB. I really think this is the only option seeing that the Pathfinder TB does not have coolant line hook up on it....I am however getting an odd idle....when its cold it will idle right around 1500...then back down to the normal ~700 (when warm)

Broaner

iTrader: (10)

Is that not what it does stock? Whats the problem. The rich condition of cold startup is what causes high idle. For some reason mine idles completely normal at cold startup.

cardana24

iTrader: (81)

Kinda man, its hard to describe on here...something is not quite right, but its not that bad. The cold idle is a little higher than it should be and the idle is a little fininky(sp?) in neutral.

---I really don't know what you are talking about saying that the car is running rich makes it idle high???????????

Badaxxima

Don't tell me to go back to my Sentra you arrogant little punk. I had a Max before this so STFU.


Great story, unfortunately, once again, you've proven that you don't know sh*t. Mechanism? Plunger? Although this is very imaginative, a quick search of the board would've turned up the explanation in the 4th-Gen FAQ's. Did you even read them? No you didn't, just like an arrogant, teenage newbie. If you did, you would've seen the post about this stupid "mod." It doesn't give you any performance gains. No it doesn't make a difference. Whatever you think you "feel" is just your imagination tickling your butt-dyno.

Click and learn

Broaner

iTrader: (10)

Thanks for the link. Thermo-element=mechanism. Plunger=part of mechanism. Where in this entire thread did I say that it made the car faster? You are correct in stating that it gives no measurable performance gains but it does make the car more performance oriented in all the ways I've previously mentioned.

The definition of mechanical;
1. Having to do w/ machinery or tools.
2. Produced or operated by machinery or a mechanism.
3. Pertaining to, in accordance w/, or using the principles and terminolgoy of, the science of mechanics.
4. Machinelike; automatic, as if from force of habit; lacking spontaneity.

The definition of mechanism;
1. the parts collectively, or the arrangement of parts, of a machine, engine, or instrument intended to apply power to a useful purpose
2. A system whose parts work together like those of a machine.

Cardana, maybe in your situation the cold idle speed is different due to boost or 5Spd(If you are). You misunderstood me about the rich condition. I'm not saying you have a problem. I'm saying that the ECU dumps in extra fuel because it is programmed to do it. There is no problem. If you don't believe me examine your duty cycle and fuel flow rates at cold startup, warm startup and warm idle. It will be clearly obvious that the fuel flow is much higher when the engine is cold. Also, this can be seen by looking at the o2 values during the said situations.

cardana24

iTrader: (81)

can you guys please argue over pm or in another thread....I am tried of getting replies and it is just you guys arguing

Badaxxima

That's cool. I don't wanna get your thread locked.