What else before I start? (Under plenum)

[BLACKonBLACK98]

Getting ready to change out all 8 injectors, under plenum hoses, knock sensors, ks harness, and ijector harness. I bought all the tools that i didn't already have accoring to the how-to.

What else should i take care of while i'm there?

Spark Plugs - OEM NGKClean EGR tube, IACV, TB - Carb cleanerClean Plenum - Easy OffMAF - Electronics parts cleanerValve Cover Gaskets - RTVTB Gasket (x2)IACV/ACC GasketEGR GasketVacuum Control Hose (?)Lower Runner Gaskets (?)PCV (?)Heater Hoses (?)Double check for coolant/secondary air hoses that may not have been includedB2318-N3301 Vacuum HoseFuel Rail Seal (?)

Any thing else i should replace/clean/whatever? Waiting on my FSM to show up along with a couple parts, just want to have all the info in one neat place.

[qship96]

What about the 35+ old, hard and brittle air/fuel/water HOSES under the plenum????????????????????????????????????????????????????????

[BLACKonBLACK98]

What about the 35+ old, hard and brittle air/fuel/water HOSES under the plenum????????????????????????????????????????????????????????

oops!

edited to include.

[qship96]

While you have the numerous electrical connetors unplugged, it is a great time to spray a contact cleaner on all plugs/terminals you can get to. Radio Shack sells a generic spray or better yet they carry the Caig brand Deoxit spray and protector.

[goody90q45]

You've done your homework so I'm sure you have TB, IAC and EGR gaskets being replaced (just forgot to mention them) as well as the 8 plenum gaskets. The PCV valve is easy to remove and clean or replace with the plenum off but it can be done with the intake on also.

While you have the numerous electrical connectors unplugged, it is a great time to spray a contact cleaner on all plugs/terminals you can get to.

Good advice. This is your only chance to clean up all corrosion from the pins of the FI and it will be easier to do the same to the IAC, TPS, CAS, EGR solenoids, etc.

Make sure to orient the clamps, especially the rear fuel line clamps, so you can access and tighten them with long screwdrivers with the plenum on. What's the member's opinions on double clamping the fuel lines and coolant lines to avoid future leaks that so many of us have every fall/winter?

[maxnix]

What's the member's opinions on double clamping the fuel lines and coolant lines to avoid future leaks that so many of us have every fall/winter?

Fuel line leaking in particular is because the fuel line has hardened and lost its elasticity. Most of the metal ends are bulb flared, so I really don't see how an extra clamp will help an old hard brittle hose.

[BLACKonBLACK98]

You've done your homework so I'm sure you have TB, IAC and EGR gaskets being replaced (just forgot to mention them) as well as the 8 plenum gaskets. The PCV valve is easy to remove and clean or replace with the plenum off but it can be done with the intake on also.

the only gaskets that came with "the ultimate hose kit" were the intake manifold gaskets. this kit is turning out to be less than "ultimate" imo. also trying to cross reference with the hose diagram/list is next to impossible since a lot of numbers don't match up.

i've added to the list: tb gasket (x2), iacv/acc gaskert, egr gasket, and vacuum control hose. anything else? i only want to make one more order.

[maxnix]

Lower runner gaskets and PCV valve. Good time to do heater hoses if they are suspect or 10 years old.

[snobrder]

What is the difference between the Intake - Manifold gasket and Intake - Plenum gasket?

[BLACKonBLACK98]

What is the difference between the Intake - Manifold gasket and Intake - Plenum gasket?

same thing according to the part number. like i said theres alot of inconsistencies between the nico tech list and the list i got from i.o.s.

[snobrder]

If we can get some more input here, this is the last piece of the puzzle to make sure I have everything I need. I found this very helpful and Im sure others will to once complete.

[3Q Jay]

well, the upper to lower plenum has 8 big thick o-rings (not true o-rings, but the idea). the lower runners to cylinder heads are 2 typical intake gaskets. 90 and 91 will have the siamese ports.no one mentioned O2 sensors, so i will. straight shot down the driver's side with plenum removed. ps marginally easier.the 'ultimate' kit may or may not have all the coolant hoses, be sure you ask for ALL of them. same with secondary air hoses.for the ultimate, use B2318-N3301 gen-u-ine vac hose andA6440-N7686 fuel hose. don't think infiniti dealers were tightening fuel clamps under warranty very often......

[snobrder]

Ok so these are intake manifold gaskets right?



And these are the intake plenum gaskets?

[BLACKonBLACK98]

i do not think you are correct.



intake manifold gaskets aka intake plenum (same thing)



lower runner gaskets

[Q451990]

I don't think it's necessary to remove the runners, although it does make the coolant hoses over the knock sensors easier to replace.

Heath

[maxnix]

Well it is if the lower runner gaskets are brittle. YOu don't wnat to go back, and after 10-12 years, I would do it any way to avoid an early return.

[3Q Jay]

the pictures are indeed what i was refering to, yes.

Ok so these are intake manifold gaskets right?



And these are the intake plenum gaskets?

[BLACKonBLACK98]

I would do it any way to avoid an early return.

thats the idea. i want to do as much as i can so hopefully it will be a while before i have to think about doing it again.

couple question/comments:

part number on o2 sensors? i'm assuming they're bosche oem.

is it true about being a good time to change the fuel fllter? haven't got my fsm yet so i don't even know where it is.

[snobrder]

thats the idea. i want to do as much as i can so hopefully it will be a while before i have to think about doing it again.

couple question/comments:

part number on o2 sensors? i'm assuming they're bosche oem.

is it true about being a good time to change the fuel fllter? haven't got my fsm yet so i don't even know where it is.

Dude the fuel filter is easy as hell and nothing has to be done beforehand expect release fuel pressure haha its on the pass front side of the car

[BLACKonBLACK98]

hmmm... sounds good to me. i wonder why it was said that having the air assembly off was a good time to change it?

[snobrder]

hmmm... sounds good to me. i wonder why it was said that having the air assembly off was a good time to change it?

Hmm I have no idea, the intake is on the opposite side of the car hah

[elwesso]

o2s and fuel filter wont be any differetn with the plenum off. Removing the runners is nice because the runners get really dirty and theyre tough to clean off the car.. Personally, I like removing everything so that basically you're left with no intake or coolant hoses at all, and then put everything back together, that way you know the whole story, if something needs replaced you do it, and if you skip something and it fails later, you'll have a better idea on what went wrong.

[Q45denver]

There is also a rubber seal between the fuel rail and the intake manifolds.

[BLACKonBLACK98]

keep it coming you guys. glad to finally start taking things off of the list. everything i'vemarked with a (?) is something either missing information (official part name, part #) or that i'm not sure will be any easier with the plenum off. if you'vegot something to add on those lmk.