Crusher103

iTrader: (10)

good write up, although it would be easier to just delete the egr

marktab

Hi Crusher -- thanks for the positive feedback -- some people get annoyed and then choose to remove the EGR altogether -- I discuss that option in my Question & Answer post

defiance

iTrader: (1)

Marktab this is great infomation ! I will be tackling the task in the near future as my max has over 200,000 miles it.

I can only imagine how much crud is built up in that tube right now and making my car ping. My question for you is after all this cleaning you have done did you clean your throttle body ?

A clean one will help smooth out your idle and give you more torque off the line.
I noticed this immediatly.

defiance

iTrader: (1)

compare the two parts

http://www.courtesyparts.com/maxima-...1958_1970.html

http://www.courtesyparts.com/maxima-...1785_1797.html

I dont know if the 5th gen maxima egr tube will fit the 4th gens...

AustinTylerDean

iTrader: (1)

Rated high for detailed pictures and close ups. Let no one rain on your parade for re-doing a how-to so thoroughly.

marktab

Thanks -- and, as you know, it's a how-to which affects all Maxima owners, and the topic is not covered well in the service manuals

marktab

Hi -- I studied the diagrams, and though the tubes are in the same location with the same part numbers, the picture indicates that the parts are slightly different for 5th generation. I can only speak to 4th generation.

marktab

Thanks for the feedback -- I believe your pinging will reduce if not eliminate by cleaning the tube (and for that reason, I don't know that blocking the EGR system is an optimal solution without other engine adjustments).

I did speak about cleaning the intake area by the IACV assembly, and when you see how much crud might be in there, it's amazing. I even need to scrape some of the carbon. I'm not surprised at the amount of carbon, but it's sad that this much builds up between the filter and the cylinders.

To answer your question: I did not clean the throttle body at this time since I had cleaned it when I last cleaned my K&N filter (I replaced the factory filter with a round K&N). However, it would be a logical concurrent maintenance since the parts are in the same area.

caseymaxima

iTrader: (1)

I had the CEL on with a code 400, however I didn't want to tackle the cleaning myself. I had a local shop do the job, and I ended up paying $240.00 to have the job done. Did I get ripped off? I am having a hard time finding a good shop now that my mechanic of many years (at least 20) has retired. The shop that did the work claimed that they worked on my Maxima EGR tube for about 6 hours.


Thanks,
Zack

defiance

iTrader: (1)

Well i dug in there tonight but couldn't complete the job that damn egr tube is a huge pain in the *** !! I took everything apart to clean the IACV since I cleaned the TB one week earlier and noticed big improvements.

That is a job for one with power tools, I dont see how its possible for someone to clean the egr tube with hand tools alone, I might have to get a mechanic for this one.

I dont have a CEL for it yet so i still have some time tear it all down again.
Im gonna have to take another stab at it cause theres no freakin way im paying a mechanic 100 - 500 bucks to do it.

marktab

Hi Defiance

My EGR tube was completely blocked, and I was able to use a small screwdriver and fuel-injector-safe carburetor cleaner to clean it out (and my only expense was the single can of cleaner).

Because of the twisty angle, I believe it would be hard to find a correct power tool fitting to get the rest. I have a Dremel, and I suppose some of the extensions might be OK for the tube opening, but since I made good enough progress with a screwdriver I did not use power tools. It might be possible to soak the whole tube (which is all metal, once the gaskets are removed -- I reused my gaskets) in solvent. I have cleaned some metal parts in the past with Simple Green heated to below boiling on a regular stove. Soaking is a more patient route, but might produce better results inside the tube body.

Also, I'm with you -- there is no need to pay someone else. Appropriately lubricating the nuts and bolts during installation will make removing them easier (next time).

marktab

Hi Zack -- the fair amount to pay depends on the market hourly labor charge in your area. I believe an experienced Maxima mechanic using my directions can complete this job in three hours. I am NOT surprised that it took them six hours because neither the official Nissan repair manual nor any of the other commercial repair manuals cover this topic well. In other words, I do NOT doubt that this job actually took them six hours. Hopefully they were able to additionally clean the IACV assembly and port opening (as I recommend on this thread).

This cleaning is straightforward, but it is not obvious how to best accomplish the goal. Thus, I would advise anyone hiring a mechanic to print out this topic (hopefully in color if possible, but black and white will be OK too) since there are removal tips in this thread which might easily save even an experienced mechanic several hours. You can multiply my three hour estimate by the hourly rate to see if the total makes sense for you. This job is almost completely pure labor, and I spent only about $5 for a can of cleaning solvent. However, my hands did get dirty.

defiance

iTrader: (1)

Marktab

Is it absolutly required to hackthe one screw to get it off ?
other then alot of twisting and turning the hacksaw part seems
like the impossible part to me.

marktab

Hi Defiance -- Bolt hacking is the most patience-testing part of the process. Without doing it, that one nut on the EGR tube bottom cannot slip off beyond the silver color exhaust pipe (in the pictures). I did not hack much off, and if you see in my pictures, I took off only what I call the "tip" of the bolt. It took a while for me to do it (maybe 1/2 hour?), but once done, it never needs to be done again. Putting plywood on the engine helped my body position for this step.

One alternative solution is to remove that silver-color exhaust pipe. If you have ever removed exhaust parts before, they somehow seem to attract rust and therefore nuts which will not move. I do not know what it would take to remove that pipe, but perhaps removing other parts before getting to perhaps rusted-on nuts. A third solution would be to cut the pipe, but then it would have to be fixed. A fourth solution would be to melt the pipe, and bend it out of the way. These last two alternatives seem to me more difficult than hacking the bolt.

Because of the angle and position of this bolt, I do not believe it is wise or advisable to try to use power tools to hack it off. If you had the correct clamp and regular drill bit it might be equivalent to hacking, but I was not willing to put a power tool at that awkward angle. Perhaps an advanced mechanic would have a power tool trick, but I am NOT advanced and I do not have any tricks. If the bolt were more accessible, then I know -- for sure -- that I could use my Dremel with my current fittings to cut it. However, that specific nut is too physically embedded into the engine and too close to the silver color exhaust pipe, and my Dremel skill is not good enough.

I can, however, patiently hack -- hack -- hack....

It worked for me.

papilgee4evaeva

A month late, I know...

... but thanks, OP, for posting this. I'm gonna try to tackle this job on my wife's car in a couple days.

Question: what do you think would happen if I *accidentally* sawed off more of the bolt than was necessary?

marktab

Hi -- it's never too late to do this maintenance, and I will be doing it myself again. However, next time I will not need to hack the bolt.

To answer your question: I do not see how you could cut off too much bolt if you were using a manual technique (like my hacking recommendation). My method can be done within 1/2 hour, muscle force only on one bolt. It is possible to loosen the nut without removing it (and if you could then slip it off without hacking -- which I believe is not possible -- then good for you). The hacking is done best with the nut on, not even loose, since a nut in place helps prevent cutting off too much.

It is possible to take too much off -- and do more damage around the area -- if you were using power tools. I do NOT recommend using power tools because there are other metal parts there which could be damaged and potentially expensive to replace. The bolt is in an area deep within the center of the engine compartment, and to either replace (or repair) an overhacked bolt or any other parts will be expensive if you pay someone to do it. Forceful solutions -- perhaps including knocking off the bolt with force, or even heat solutions -- could easily damage the EGR tube or other parts in the area.

If the nut is still on the bolt, that's the best time to do the hacking. I only had to hack the flanged area at the tip of the bolt, and that's enough clearance to slip the nut off. I could have gone deeper, but I didn't. The point of the hacking is to allow the nut to slip off the bolt.

That all being said -- it's your car, and if you decide to experiment with other solutions, let us know what happens (no matter what the outcome).

papilgee4evaeva

Correct, it's not possible to get the nut (or the thick washer [??]) out if the bolt isn't hacked partially off. Also, one thing I have to add... MAKE SURE YOU BOLT THE IACV BACK ON COMPLETELY. I had a bad whistling sound and a vacuum leak because I forgot the bottom bolt.

I just cleared the code a few minutes ago. I'll have a final verdict later on, but thanks once again for the tutorial and pics.

marktab

Thanks for adding the tip on the IACV -- I would expect perhaps whistling because it's part of the vacuum.

Glad the repair worked out

edwardh1

its a bad Nissan design. Makes you wonder if they ran any test cars past 50,000 miles before introducing that egr pipe design!!!!????

papilgee4evaeva

It is my firm belief that all of the emissions equipment design on 4th gens was either an afterthought or a very, very dirty trick.

Chances are, though, that they tested it up TO 100K, but not beyond... which is when most owners start getting codes.

edwardh1

================
Mine clogged up at 70,000 miles

papilgee4evaeva

Mine first threw the code just before 100K. Incidentally, it was not long after my wife started putting cheap, low-octane gas in the car. Threw the P0400 code and blew the KS at about the same time.

Oh My Achin' Max

Hi ... I am a newbie to this forum and just finished the EGR cleanout today. One suggestion I would make about hacking off the stud: I used my Dremel tool and a cut-off disk. It took about 20 seconds. Just watch what you are cutting. The pipes are close. BTW, I used the photos and they were superb. That is what my Haynes manual should have provided. Having said that, I say a pox on Nissan's so-called engineers for making access so difficult. Anyway, it done and hopefully good for another 100k.

williamhood

Yea, the EGR tube with the big nut on it may be fine if your are working on the engine OUT of the engine bay. Poor design. I spent several days back in the spring doing many, many little jobs like this to improve my car. I have 189K on it now and after I: cleaned intake manifold and all ports, mostly clogged EGR tube, EGR sensor, throttle body, IACV valve assembly, replaced both front and rear leaking valve cover gaskets (USE RTV!!), cleaned the MAF sensor, used BG44K in the fuel tank to clean the injectors - I had a quick starting, 28MPG highway, no pinging, kick in the pants Maxima again! I LUV it!

marktab

Thanks for the feedback -- I'm glad the Dremel worked for you. I have that tool, but because of the angle and the chance of cutting the exhaust pipe, decided to use the manual hacking method (which is the approach I recommend). Power tools can help, but people have to be careful. I'm hoping my Maxima has many miles left!

Pona64

hey guys just got a 98 maxima se and this is the first thing i did and it was completely plugged. hacking off the bolt was time consuming, took forever. Anyway great write up 10/10.

marktab

Hi Pona64 -- glad it worked out. Anyone acquiring a 4th Generation Maxima should follow your example, and include this step in the initial maintenance. Thanks for the feedback.

addanis01

hey guys thanks alot this has been a big help

cashoit

jus to be sure...this thread is the cleaning / removal procedure for the EGR guide tube correct.

second...why do you have to hack off the bolt. and how much of the bolt do u hack off

third...is there anyway of cleaning this w/o the removal process..injection cleaner perhaps or seafoam??

marktab

Hi --
1) Yes, this procedure is for cleaning the EGR tube
2) Only one of the two lower bolts needs to be hacked. The purpose is to allow the nut to slip off since there is an exhaust pipe in the way. Only the tip needs to be hacked, and since you are hacking with the nut on it would be hard to cut off too much.
3) I do not believe solvents can do as good a job. In my case and many others the carbon needed to be scraped off. The carbon sticks similar to burnt food in a pot or burnt carbon on a barbecue grill. Also I would not want these carbon chunks to be sucked into my engine.

cashoit

when u reinstall the IACV...does the idle have to be re-adjusted??

And to be sure...do not remove any nuts until the lower bolt has been hacked..then remove each bolt carefully.

Where can the gasket be purchased. THe EGR isnt supposed to be removed as part of normal maintenance. But ima try this anyway when it gets warm enough

marktab

Hi Cashoit
1) No you do not need to readjust the idle to clean the tube. However, if your vehicle is overdue for a tune up then you could check your idle and do other steps like upgrade the original spark plugs to NGK platinum.

2) Yes, be careful when hacking the bolt. I hacked mine manually, and that's the safe method I recommend.

3) For the gasket -- try a NAPA store in your area (or look online too).

4) A scientific comment on the term "normal maintenance". The term "normal" best refers to the averaged effect of what all owners do for their vehicles. I believe if you or I followed the "normal" path then our vehicles would not be in great shape, because I continue to believe from observation that most people do not change their oil (for example) as frequently as they should.

Nissan's "recommended maintenance" list was based on other vehicle years, and was published (and legally examined, since some of it refers to when some parts would remain under warranty) at the time these vehicles were manufactured. The "recommended" list is authoritative, but is technically a "best guess" on what these vehicles need.

Our "actual maintenance" should be based not only on the recommended guidelines but also the actual documented experience of other owners. My documentation was a story supported by pictures. We can do better than both "normal" and "recommended" lists by following tips and tricks from experienced owners and professional mechanics. I only know a few tricks, but this forum in one source of many other helpful tricks

... by the way, I believe these same principles apply to our health and education and (spiritual) relationships with other people -- we should strive to do better than "normal".

Gary Mastro

After removing a few things to have reasonable access to it, I found using a grinding wheel on a cordless Dremel super easy to shorten that stud. Three minutes, max.

antiguan

good job, thanks

cashoit

I think that if u use injector cleaner regularly then that will help to keep the carbon buildup in the EGR down...

cashoit

Wise words bro...i agree

marktab

Hi Cashoit -- I doubt it. The EGR tube sucks directly from the exhaust (outtake) not the areas that injector cleaner cleans (which is for the fuel system, not the air system). That being said, I do believe in cleaning your fuel injectors since varnish can collect on the tip over time, and clog the efficient injection of fuel.

You can still propose a scientific theory for why you believe fuel injector cleaner (assumed through the fuel tank) will affect the EGR tube.

Justaguy

I went to the dealer today to see how much they would charge to clean the EGR. They advised me against it since I don't have any codes (I have 144,000 miles on it with no codes but noticing little acceleration, so I wanted to get it cleaned).

The dealer claimed that it's a tight spot and other things may break..bla...bla..bla. After I insisted on a price, they quoted me a few hours (maybe more if something breaks) @ $90 a hour (yup this is in Canadian funds).

I then went to the pieces department and I got a quote of $300 just for all the parts (TB/IAC gasket, EGR valve and Solenoid). The EGR valve was $250!!! Yikes.

So I figure that if the dealer were to do this job it would be around 3 hours of work ($270) + parts ($300 -I'm sure they would not hesitate twice to replace the parts = ~$600 + taxes = $700.

I'm going to try and do this myself and see how far I can go. I don't think I'll replace the EGR valve or the Solenoid. Yeah?

cashoit

LOL...here is my scientific theory then

The fuel injector cleaner flows through the fuel lines to the injector...then is burned in combustion ..and leaves as exhaust. So my theory is that the injector cleaner MIXES with the fuel... then some (im thinkin a very small amount) of the cleaning particles remain in the exhaust and then is recirculated through the EGR. So some of the cleaning particles still clean as the exhausr but u would need to use the injector cleaner pretty regulary to see effects.

Justaguy

Well, I started the process in this step-by-step instructions and yes patience is needed I'm not a mechanic and I was afraid of messing things up with the wiring. I even labeled the tubes so I know how to put them back and not mess up. I spend 3 hours and I'm at the point of hacking that little well-rusted nut. I put some PB blaster and I'll start up tomorrow nice and fresh.

The process is medium and certainly do-able but you need patience and a good back. Did I mention how many times my head bumped the hood?

My EGR tube is all clogged and I have 170,000 kms.

The flexable socket certainly came handy .. Once I get this thing cleaned, how can I keep it clean?

Has anyone tried Auto-RX? It's suppose to remove sludge and stuff...maybe I'll use it as a regular maintenance...( I don't think it will remove an already clogged EGR tube).