speedvision

just did my maf, iacv, tb, and egr tube. Whew. what a pain. Feel very cool now knowing all that nastyness isnt there anymore, also adjusted idle... purrrrr's like a happy kitty alright. (on my 98 gxe max auto 175k)
($15 - maf cleaner/ tb cleaner/ carb cleaner -$5/ea)

+1 everyone who hasn't should do this.

+1 Thanks for the Great Tutorial ! ! ! Excellent job!

sanchalanam

Thank you for all the pictures and info. My car was stalling almost at every traffic light. After i cleaned MAF, IACV, TB on my 96 Maxima, stalling problem is completely gone. However, Check engine Light came back for KS & IACV (code 34 & 25). I reset Check Engine light multiple times but its back again after few miles. Can I ignore IACV code as my Maxima is not stalling any more?

Thanks for any suggestions.

Sanchi

domano 68

Just cleaned my MAF, TB and new plugs in my 99 with 70k miles. Did this due to stalling at stop lights. It still is stalling.

I did not take the MAF out of the maf tube, just pulled the maf tube out of the car and sprayed the MAF with CRC from both ends. I have searched for pics here of the MAF cleaning process and have found none. Do I have to pull the MAF out of the tube to spray with CRC? Just wondering here if I did not do a good job of cleaning the MAF.

So if maf was cleaned correctly what else can i look into, pcv? TIA!

Caticorn

The MAF doesn't come out of the tube. You just do it like this.

I did it once, and it fixed my problems temporarily, but my loping/stalling/hesitation slowly came back, so I did it again and it fixed it, but even more temporarily. I eventually had to replace the MAF and now it's gone for good.

You might be ready to throw in the towel and get a new MAF, but be absolutely sure it's the cause before doing so. 70k seems pretty early for the MAF to go out. Have you done the EGR and IACV?

chico102388

i already did the TB and MAF now i have to find time to clean the EGR awesome write up.

acvc

I've got the IACV code on the ck engine. I took it off today and cleaned it good according to previous post. The ck engine light and same code still returns . Any suggestions?

browne

great write up.. wish i saw this earlier. i just cleaned the throttle body and maf but didnt know where the iacv was.

do i need to take the whole throttle body out to get to the iacv or can i unplug the 3 socket and 1 vacuum tube and then unscrew 3 bolts thats holding the iacv???

nab911

iTrader: (1)

I just got a 95 se and it runs perfect except on start up. Right after cranking I have to blip the throttle and then it runs great. I just seafoamed but might try cleaning some of these pieces (brand new MAF so no need to go there) and see if I can't help it out.

browne

i'm not sure if it was cleaning the maf or tb or both but my car starts a lot better. i was having trouble starting in cold weather but now it cranks pretty hard. my idle is also hovering around 700-800 before it was around 600.

ddcoons

I spent what seemed like hours trying to get the carbon out of my EGR tube. I used carb cleaner, wires, pipe cleaners, degreaser, water and nothing would budge the gunk in the middle of the pipe which was just out of reach. I even let it soak overnight with no apparent improvement.

Actually, my tube became more thoroughly clogged with my attempts to clean it.

So it occurred to me that perhaps oven cleaner might help. I got a cheap can of cleaner at the dollar store ($1). I sprayed as much as I could into the tube on both ends, then I set the tube in the oven and ran the oven through a cleaning cycle.

After this, I was able to break loose the carbon in about 10 minutes.

95max87

Thank You for this thread. I know I am posting on a kind of old thread but I just started having the same problem on my 95 max. The pic by pic is a great way for people to follow along. will post results when I am done.

Darkstonian

Great write up man, after lurking here for a year, I finally tackled this job for my 98 I30. PITA for the hacking, and removal of that 1 bolt. 1/8th a turn took forever, lol. Though for you guys that do plan on it, remember to clean out the hole that the egr guide tube connects to the throttle body. That was completely blocked as well. It's like a little bowl, so now I see why it clogs like that. the end of a wire hanger and a small screwdriver worked best for me. I also used a can of compressed air to blow the carbon deposits out after I loosened them. I was lazy, I just bought a brand new guide tube for 30 bucks from the dealer. Runs smooth as butter now @ 170k, and idles quiet. Long live the I!!

lyhnedk

nice write up... i will be doing this to mine after i have seen this

seoulfulwon

I can't see any of the pics; even from the printable version, the links are not displaying an image. Does anyone have these pics or is there another way to see them? The write up is great, but I would like to have the images to ensure that I'm performing this properly. Thanks

Cebby

iTrader: (6)

I need these pics also. Throwing P0400 & P0325 codes. Heard that the KS code is a ghost so I just need to clean my EGR guide tube to fix. Need to do this for inspection!!

carsnwomen91

i hope you don't run into problems with the ebay maf... just go the the junkyard and yank an oem one off. should be around $50

ash0621

WHERE ARE THE PICTURES

mikeg75

The ebay MAF I bought in Jan 2010 to fix the stalling issue I was having at that time gave out a month ago, and horrible stalling ensued. Luckily I had the original MAF in the garage and just cleaned it and put it back in. It ran 100x better but with some hesitation and occasional stalls with the original MAF put back in, so I ordered a new ebay one, this time for $45 vs $95 for the other one. The stalling is completely gone now but it still has some hesitation, so next weekend I'm going to take out the TB, IACV and EGR tube and clean everything up. I've got all new gaskets and to save time, I bought a new EGR guide tube so I hope this job is relatively painless and fast, once I start it.

I'll post back once I've done the job, to relay the results.

Thanks again to the OP for the informative step-by-step and to JHolley re-posting the pictures.

dwapenyi

iTrader: (3)

Maybe you should try this first;

http://forums.maxima.org/5th-generat...troke-oil.html

richard.miller11

I was looking to clean my IAC valve too. Is there a way you can fix the images I can not see the images you posted.

richard.miller11

never mind, after I registered I can see the images on the last page. Sorry.

phenryiv1

iTrader: (19)

First post fixed.

mikeg75

I'm planning on tackling (attempting) this project on Saturday since I already have all the parts but I will also be picking up some of the 2-cycle marine oil additive as that sounds promising as well.

I hope to get the slight hesitation on accelerating to go away after I clean the TB and IACV, and put in the new EGR guide tube I bought. I'm going to clean out the orifices and vacuum out the crud after scraping them. My only concern is that the studs attaching the EGR guide tube on the bottom, get stuck, like some of the recent posters have mentioned.

mikeg75

Holy shnikies was this a difficult project!

Started at 8 am, finished at 8 pm, but halfway through, I was ready to quit before even removing the EGR guide tube, which to me, would make the project a fail. The EGR-BPV and the EGR valve being in the way make this job really hard. I ended up leaving both more-or-less in place, and working around them. I used a piece of plywood to lay flat and saw off the end of the stud on which the nut for the lower right EGR guide tube is attached, but I had to constantly flip back and forth from using the plywood to going at it from the driver's side. A lunch break and reviewing a couple threads on here gave me the courage to start taking off the EGR guide tube bottom nuts. Once I got them to break free, I committed to finishing the job.

Without taking the car for a drive, I can say that the idle seems more solid. When I put everything back together and started her up in the driveway, it idled at 900 vs 650 RPM prior to the job, so I adjusted it down to around 650 or so. I haven't had the chance to take her for a test drive but I'm confident that this effort made a difference in how my car idles, and I bet it will save gas now that the idle has been adjusted down.

I'm planning in putting a little 2-stroke marine oil which I just picked up yesterday at Walmart to see if it lowers the amount of noise I hear at idle but I can already tell that the stick shift seems to vibrate the way I remember when the car was new to me, in 1999 (4 yrs old at the time).

My joints ache more than anything else, from the constant shifting around.

ShocknAwe

iTrader: (3)

lol congrats on a DIY completed! Instead of 2 stroke I would use MArvel Mystery oil.

ck1995

To make using the hacksaw blade easier, I used a leftover pull handle from an lawnmower pull cord. I shoved one end of the hacksaw blade into the pull handle and was able to use that as a handle for the hacksaw blade. Made it a lot easier to use and only took a few minutes to saw the bolt off.

72240z

Awesome write up... I have to be honest guys, my Maxima and I have nearly parted ways a few times. It's not her fault, a teenager took the best years from her. He abused her for years and then he was ready to send her to be `picked a part` in some desolete South Dallas junkyard.
Ok, so all we need now is a new movie titled, `Les Misarables de Maxima `...

Feel good maxim.org ... this forum helped `impove her quality of life` ...

signals

I am having aweful time getting bpt valve (with two screws on top and a bottom connecting nut) out of the way to access the bottom nut holding thr agr guide tube. How come no one has encountered this among many obstacles to reach to the bottom nuts og the egr tube? I am desperate. Can some one please clarify clearly step by step? I have removed both the screws on top and the bottom nut attaching the bottom bent tube. The assy still does not move away. What is holding it?
Thank you guys

dwapenyi

iTrader: (3)

When you're doing the EGR tube, you should leave the 2 top nuts in and first saw off the stud of the the non-threaded part of the bottom to get the bottom nut off.

From the instructions.........

EGR guide tube removal:
- Unclip the large coolant hose clip (2 pictures up) with a flat head screwdriver
- Locate EGR guide tube - it is attached to the plug whose bracket you just removed
- Locate the lower rear stud of the EGR guide tube not be confused with the EGR tube that is located forward left of it
- Hacksaw the non-threaded part of the stud off (you need ~ 3mm off of it to get egr guide tube out), this is for me the most painful step as I had to do it with a hacksaw blade - can't fit a whole hacksaw in there
- leave the 2 upper EGR bolts alone - it'll make removing the lower ends easier
- Get in with your 12mm box end to undo the nut - you'll likely only get one wrench tooth position's worth of rotation each stroke but it comes out fast, you can turn it with fingers
- Carefully remove the nut and 2 washers 1 by one as not to drop it
- Use your 12mm deep socket to remove front lower nut of EGR guide tube
- Also remove the nut and 2 washers one by one
- Use your 12mm socket to remove the 2 upper bolts of the EGR guide tube
- Pull EGR guide tube off
- Remove gaskets with flathead if needed - my lower one was quite stuck, spray it w/ carb cleaner

signals

[QUOTE=96i30azn;7085286]I cleaned my maf, tb, iacv, and egr guide tube last week after some extensive research here on the org. I felt like none of the threads included directions for a total newb to do everything. Doing everything at the same time makes sense b/c if you're gonna get to the egr, might as well attack everything else while you're at it so here it is. My car is a 1999 Infiniti i30t, your car might vary slightly in terms of hoses, tubes, and plugs.................

Very good write up and tips! Unfortunately, no one has mentioned solutions to unexpected problems and difficulties that I encountered with my 97 maxima which is similar to infinity 4th gen. Here are the problems:
1. How to remove the coupled plugs (gray plastic housing) mounted on a bracket that is bolted to the IACV. Unbolting the brkt is quite tedious! Is there a trick to slide out the gray housing from the bracket without having to remove the brkt?
2. Some of the hoses are impossible/ hard to pull out (of course after sliding out the clamps), especially from the tubes with two expanded collars at the end! I am still struggling with the lower of the two hoses (in the picture they are shown as close together one below the other- top one goes to fuel filter can)! Is there some trick to pulling them out some what easily? Cant get any leverage with a flat head screw driver to push the end of the hose out of the tubing's 1st "collar"! These hoses are obstructing access to the upper bolt of the bottom part of the guide tube.
3. There is a bent tube below the BPR valve that obstructs access to the upper bolt of the bottom part of EGR guide tube. How to move this tube away?
I guess after these difficulties are resolved I would be on the home stretch
Would some one please illustrate the solutions? Thanks a lot! Item # 3 is the worst problem!

signals

[quote=signals;8748386]

wxm

iTrader: (2)

I thought I read somewhere on this board that the hacksaw can be avoided. Was I dreaming or can some one confirm it?

signals

yes, some one in Marktab's thread said that he worked from underneath the car, loosened the 30mm nut and could move the obstructing pipe away a bit to let the nut (lower part of ERG guide tube) come out.

BobMax

Thanks to the OP - Just did the TB and IACV. I think I've cured my cold start idle problem. I'll need a few more starts to confirm.

One addition on cleaning the IACV - after removal clean the manifold surface, inside the manifold opening, and the surface of the IACV.

Then you need to clean the actual valve. Remove the two screws on the backside of the IACV that hold the valve in place in the unit (not the three that hold the electrical unit on, you don't want to disassemble that). Pull the mechanism out, and clean inside there. There's a conical valve plunger that needs to be cleaned as well as the seat it closes against. That's the actual valve. Mine had lots of goo on it, and the car only has 90K miles.

Be sure to loctite the three screws holding the cover mentioned in the original posts back in - wouldn't want one coming loose in the manifold and getting sucked in.

xplicitMAX

iTrader: (1)

quick question, got a code for a KS and EGR regular flow, so assuming i should prob clean my EGR. Should i also clean the MAF, TB, IACV along with the EGR?

AMnissan

any way to remove the egr bottom nut without the hacksaw?

JvG

[QUOTE=AMnissan;9240088]any way to remove the egr bottom nut without the hack saw.

Nope.

the hack saw is the only way.

We don't use this method for fun or because we get off on masochism and pain.

It's because we have to.

AMnissan

[QUOTE=JvG;9240089]bet. Thnx