Hey guys!
I found my cold start and hesitation problem after replacing numerous things!!! So I started noticing a hissing noise coming from around my tb, I decided (for the 4th time) I would spray around my intake and tb with tb cleaner, I started to spray around my tb and got abunch on the top plastic puck piece with the plug in it on the egr and heard the idle slightly speed up for a few seconds!!! I waited and sprayed it again and the idle whent up again, I pulled my tb and air intake out and looked at the Egr, so where this top plastic puck meets with the actual valve I noticed a gap that I'm sure is not normal I warmed the car up and. Tried to tighten the 3 allen key screws but they were pretty tight, apparently you can only order the whole egr assembley not just the toip plastic part. The whole egr assembly is like 300 bucks so do you think its worth going to a junk yeard and just pulling the top of the egr off? And what's involed??? Does it just unblot or is there wiring that I will have to re soder ??? Has anyone fully disassembled a automatic egr befor???

 

So... is the actual leak a moving part? I would just JBweld that bish and call it a day

 

any pics??

i mean for those of us who havent been there yet and would like to see what you are talking about

 

That's what I was thinkin... Yea if you look at 0a Egr for a automatic its got this circular top plastic top with a plug on the top that is mounted to the metal bock with the two nipples, what would be better to use jb weld or a gasket sealer for exhaust manifolds??? jb weld would be much easier than a gewy gasket sealer. But I don't know about heat

 

Look here: http://www.partswebsite.com/nissanca...80&catid=30153

 

People have used JB weld to patch cracks in engine blocks, exhaust manifolds... ETC. It's not really made for it, but it will still be where it is were that plastic melted in a hot engine fire.

 

Roger that.

 

No I can't get a decent picture withou pulling it out, which I don't want to do quit yetmmmm but ill definitely take a pic it sealing it doesn't work! Hahaha. I'm not definate that this is my problem because its not fixed I know there is for sure a vac leak there because I can spray it with throttlebody cleaner and the revs go up about 100 rpm. Every time I spray it . But if you google an automatic 2000 maxima egr valve it will show a couple of them and its located right underneath your throttle body, it has pretty much like a top lid of a small pray can with a plug connected into it. And has a metal base with 2 vacuum lines running from it, where the plastic. Top(the spary can lid) mounts to the metal base there are 3 allen key screws holding it, I hope I described it ok, anyways I'm going to buy some jbweld and ill see if it holds up and let you know.

 

The black metal cover is only the cover for the EGR stepper motor.......you need to find out for sure where the vacuum leak is. Forget the JB weld. The EGR valve assy. mounts to what appears to a manifold spacer with a gasket and I believe a couple of hoses are attached just under the EGR. There is also a gasket under the EGR valve where the EGR "guide tube" mates with the EGR valve. These gaskets could be a source of a vacuum leak, along with the hoses.

 

Thanks P. Samson! Yea I think its actually coming from where it mounts to the manifold directly underneath the EGR valve, what is the egr mounted to can someone xplain? Is it mounted to the block or just onto the manifold tube and. EGR return QUOTE=P. Samson;7867227]The black metal cover is only the cover for the EGR stepper motor.......you need to find out for sure where the vacuum leak is. Forget the JB weld. The EGR valve assy. mounts to what appears to a manifold spacer with a gasket and I believe a couple of hoses are attached just under the EGR. There is also a gasket under the EGR valve where the EGR "guide tube" mates with the EGR valve. These gaskets could be a source of a vacuum leak, along with the hoses.[/QUOTE]

 

Ah...too bad I didn't save my old EGR valve. I replaced basically all of the EGR system with the valve, EGR tube, and EGR temp sensor.

It isn't too hard to pull out once you get the intake off. If I were in your position I would go ahead and get a new EGR tube and gaskets for the EGR tube and EGR valve. Replace those and see if it helps your situation. Those gaskets can wear over time and leak. Mine were in terrible shape, not sure if they were leaking though.

The EGR valve looks to be mounted on a manifold from the block. I couldn't tell if it was on the block itself, but to me it looked like a manifold.

When/if you replace these parts be patient and smart. There is a right order to remove the parts to ensure you can get them out and back in. I would also suggest you order new washers and nuts for the EGR tube. The new style are easier to re-install than the original nuts.

Good luck...

 

Thanks P. Samson! Yea I think its actually coming from where it mounts to the manifold directly underneath the EGR valve, what is the egr mounted to can someone xplain? Is it mounted to the block or just onto the manifold tube and. EGR return QUOTE=P. Samson;7867227]The black metal cover is only the cover for the EGR stepper motor.......you need to find out for sure where the vacuum leak is. Forget the JB weld. The EGR valve assy. mounts to what appears to a manifold spacer with a gasket and I believe a couple of hoses are attached just under the EGR. There is also a gasket under the EGR valve where the EGR "guide tube" mates with the EGR valve. These gaskets could be a source of a vacuum leak, along with the hoses.[/QUOTE]

 

Do I have to remove the intake manifold to replace the lower gaskets? or is that just when replacing the egr tube gaskets, I thought I was able to unbolt it if I just removed the intake and throttle body I would be able to unbolt it from the manifold and the lower part of the egr tube???... please don't tell me I have to remove the intake again lol


















(QUOTE=foodmanry;7867354]Ah...too bad I didn't save my old EGR valve. I replaced basically all of the EGR system with the valve, EGR tube, and EGR temp sensor.

It isn't too hard to pull out once you get the intake off. If I were in your position I would go ahead and get a new EGR tube and gaskets for the EGR tube and EGR valve. Replace those and see if it helps your situation. Those gaskets can wear over time and leak. Mine were in terrible shape, not sure if they were leaking though.

The EGR valve looks to be mounted on a manifold from the block. I couldn't tell if it was on the block itself, but to me it looked like a manifold.

When/if you replace these parts be patient and smart. There is a right order to remove the parts to ensure you can get them out and back in. I would also suggest you order new washers and nuts for the EGR tube. The new style are easier to re-install than the original nuts.

Good luck...[/QUOTE]

 

You have to remove the intake to access the EGR valve.

 

Sucks!!!!, mine is a 5 gen not 5.5 are you sure?? Everyone I have talked to says you can unbolt it w/o taking the intake off. Its just a little more difficlut with it on... And now. I'm starting to doubt that its an vac leak and the sound I'm hearing is normal... So I think I need to explain my situation a bit better, it is now starting fine, the idle is good ( I ve been putting 89 in it rather than 92 so I have filled it up with 94 and I believe that has made the idle better abd stopped my hard starting issue, so now all I'm dealing with is when its cold I start my car, it will fire right up and have good idle, but if I drive away "slowly" it will hesitate a bit. Under 2000 rpm once its over 2000 rpm its fine, I can also sit with it in "p" while its warming up and "slowly" get the rpms up to 200rpm it will sit there at 2000 then slowly go back down to around 1500 rpm (almost like I gently backed off the gas) its very odd, its not missing its not in the trans, its not like I get it to 2000rpm and it cuts off its just like I'm slowly letting off the peddle.... So odd.... If I start it cold and tap the gas it will go past 2000rpm same as driving if I'm at a stand still when cold and take off with some throttle I don't really notice it as much and once its warm it just turns into a little cut off at 1500 but barely noticeable, I've also noticed that it kinda seems shift in odd spots. I was really thinging it was a tps but its at .43 v and as I increase throttle it raises in volts smoothly! What else could it be ??? Couls it be just my tps is dirty??? Should I clean it and how??? QUOTE=foodmanry;7868186]You have to remove the intake to access the EGR valve.[/QUOTE]

 

I thought that you were convinced that it was a vacuum leak in the area of the EGR? On a cold start warmup particularly at colder temps (especially for the first minute or so) there may be a period of time where the engine operation, particularly under load, may be a little "quirky" (and until it essentially reaches normal operating temp). These cars won't even go into 4th (OD) and/or lockup the TC until the tranny fluid is warmed up to 40 deg. C, if I remember correctly. If the car is performing nicely when fully warmed up with a stable and correct idle RPM then I would not get too carried away troubleshooting for a little hesitation or hunting during the warmup. The TPSs on these cars are pretty bullet proof unless contaminated with fluid. What noise was concerning you?

 

At this point I agree with P. Samson...your car is old and it won't run perfectly all the time. Not sure if you have better things to do, but if you do, start doing them and worry less about your Maxima.

Depends on the intake, but if you are stock, take it off...trust me.

 

this is definatley not normal..... when the car has sat and gotten cold, i fire it up and wait for it to warm up in park and give it a bit of gas to get it up to 2000 rpm, it will get there, but.... it slowly works its wayu down to 1500 rpm ( its like if you got your revs up to 2000 rpm and slowly took your foot off the peddle) BUT IM NOT TAKING MY FOOT OFF THE PEDDLE!!!! HAHAHA) i can press harder and it will increase but its like there is a blank spot in the throttle or its locking it at 1500rpm and then it will shoot up and over 2000rpm, if i drive it when its cold it would (yea i guess feel like a miss but its not!) once its fully warmed up its decent, im noticing that when im driving in the city it unexpectidly shifts into od then when i go to accel. on it (sometimes theres a slight delay or hesitating) then kicks in and takes of also..... when its warm and i take off from a light i can still somewhat feel that hesitation at around 1500 rpm, its hard to explain..... is there an o2 sensor that is for cold starts??? its really annoying with no ses light!!!!! i just want to figure out what it is befor it creates somthing worse.....

p samson you live in vancouver b.c. right???? i wish i could show you one time maybe you could explain it better for me, i live in langley just off the number 1 so were close!!!!!!!

im sorry if im not explaining myself but i have replaced and cleaned tons of shyte, takin it to someone twice and they cant figure it out..... its very odd

i thought it was a vaccum leak, but im not so sure because my idle at cold start ups is good and its turning over better when cold versus hot ever since i put the highest octane i could (94) in it it just at that part in the throttle and its way more noticeable when cold but still there when hot i dont think its a tranny issue because it does it in park as well i have tried to eliminate everything

02 sensors only work in closed loop( when warm)- no not that then
tps is reading .43 at idle and has a steady increase as i increase throttle- no not that then
replaced cts- nope
cleaned maf- not really sure how to test it ive tried looking it up but its too technical for me to even understand i just wanna know what wires to test and if i want my volt meter on double digits or another setting and what readings to look for. i did unplug it and drive it when it was warm and made no difference other than not revving above 2500.
- cleaned throttlebody
-replaced plenum gasket, tb gasket
- i can hear the valve open and close in my egr so im assuming its good.
-replaced plugs and air cabin filter
- removed fuel pump and inspected fuel filter it was perfectly clean!
-tested coils
-added sea foam to my tank did nothing.

what else is there.....

a clogged cat????

i also notice lots of vapor coming from my exhaust pipe ( more than other vehicles around me!)

tranny fluid is nice and fresh looking and smells fine coolant is good and im not losing any noticeable amounts, oil is fine no water in it!

im going crazy!!!!!!!!!!!!!!

sorry for the long post in advance!

 

Not sure if you have better things to do, but if you do, start doing them and worry less about your Maxima.



i cant it drives me crazy it feels like the shift points are off unless overdrive is turned off, and this cold start up is driving me bonkers

 

Forget about the amount of exhaust vapour......it'll vary, and don't compare it to other vehicles around you. The EGR valve operation should not be audible to you. It should not be operating anyway at any time where you could possibly hear it. If you are hearing any kind of "hissing" at idle then that could be a vacuum leak. I suspect that you've been hearing the IACV operating (it operates when you turn the IGN. switch ON and OFF). I can't really tell from your description of the "hesitation" what is really going on but I'm wondering if you've got an ignition miss. "Bench" checking of these ignition coils with a multi-meter does not necessarily prove them out as being good (they break down under operation). They have been a problem with these cars. I had a "very intermittent" miss for about six months before I got a P1320 code and many more missing events before a got the cylinder code (and the SES light), and replaced the coil. You mentioned some items that you've done with the car, but I don't see spark plugs......how many miles on the car? Just stick to Chevron 91 here.......94 is overkill and money down the drain. An engine that does have performance issues can cause wonky tranny shifting. But, for example......under light loads they will upshift fairly quickly. Mine will loaf along at 60 kph with the RPM at barely 1200. It's in 4th. The MAF is really the primary sensor that "drives" the fuel delivery but interestingly enough it's the one sensor that has been shown to cause ongoing engine operating issues but not set a code and/or put on the SES light. Has the car ever been hooked up to a scantool and had a knowledgeable person look at the live data? The FSM has data specifications (for comparison to the problem car) that is used to help troubleshoot performance issues. I'm on the north shore so hopefully you can find someone a lot closer to help you.

 

hey p samson, yes i changed the air filter and plugs right after i noticed it doing this. i work at kirmac collision in surrey and our brother shop (budget) has hooked up a scanner for live data and couldnt find anything, they see what i am talking about but there prespective on it is carbon build up.... they also tested it when it was warm and its not near as bad when warm( but def still there).... its not carboned up i know that for sure, i cant see it being a miss because i can floor it cold or hot and there is no miss and it drives strong its only with gentle throttle and at one certain point in the rpms, its too ! im really leaning towards a a/f problem, either with 02 sensors or vac leak or maf, but the cheapest i can get a refurb maf for is 250 with a core return from lordco, or 600 from the dealership! i cant afford to cough out that much doe on a assumption but..... i have a maxima at my work right now but its an 02... will it harm my motor if i throw in that maf sensor being two years newer with the thermister and take it for a cruise after disconnecting the battery to reset for the new maf? cuz then i can completley eliminate the maf.... also tomorrow im payin the 70 bucks to get the smoke machine hooked up to it to see if there is a vac leak, i know they shift soon at light throttle, 1-3 is fine i just notice that sometimes it feels like its thrown into overdrive at the wrong time, but that could just be me and im not so worried about that right now, i thought i could have something to do with my main problem, yea the exhaust thing was also just a thing for me to throw out there,i figure a vac leak would cause unaccounted for air into the system causing more than normal "clean" fumes out of the exhaust.

so if you or someone approves the 02 maf in my 00 ill give it a wirl so i can eliminate the maf

tomorrow i will get the smoke test done and be able to accuratley detemine if its a vac leak, and go from there! thanks for your patients with me!

p.s. small world!!!! i grew up in north vancouver right off lonsdale!!! and w29th i just moved from there out here like 4 months ago!!!!

edit: it sounds like the iacv, i put a screw driver on the egr cap and listened, i thought it was coming from there..... maybe not. hahaha

thanks for you help ill keep you posted
Brady Clendenning

 

If you disconnect the MAF/or remove it the ECM will see no/low voltage which will put the system into fail safe with a fuel cut at about 2400 RPM. The MAF sensor element and the MAF tube/housing ("the MAF assembly") are basically matched together, whereby the MAF tube ID diameter and ID profile are critical.......read as "calibrated" for the particular car (model year etc.), so I personally would not try to mickey mouse this. There were warnings in one or more TB years ago in relation to not mismatching MAF sensors and the tube/housing when replacing MAFs. Do you have the AirCare printouts from the AirCare emission tests prior to the new scantool check only inspections (in other words, these printouts would be from the AirCare testing prior to about two years ago)?

 

no i dont.... just bought this car like a 2 months ago, i didnt notice it in the first 2 weeks of owning it, i filled it up with lower octane, and when i was reading the owners manual i saw it requires high octane i was half full and filled it with 94.

ever since the fill up with th reg grade ive noticed it, not that its anything to do with it but thats when i started noticing it.

ive heard of people using the 02 sensors in 01's or vice versa, i just figured as a quick test it might have been useful

ill let you know what happens tomorrow.

thanks p. samson

 

So... There is no vac leak at all, a tiny little leak coming from the egr but my mechanic says its ok . He created a a leak to see how it reacts and when a eak was created it increased fuel to make up for it, so he says everything seems fine there, the o2 sensors are good t. There going to do a h vac on it to clean out the carbon build up, if that makes no difference I guess I'll buy a new maf for it and go from there, any other ideas???

 

So I put a new fuel pump, the check valve was shot so replaced that as well, after the new pump and the H vac system pumped through it. It is running a lot better, its got some new found power! but can still feel the cold hesitation.... I guess all that's left is a maf sensor now...
Ill get one in a few weeks and let you know....

 

Not sure where you are getting your parts, but you can get an OEM replacement MAF sensor (sensor only) for about $100. Do you know who Dave Burnette at South Point Nissan is? I suggest calling him to get an exact quote. It isn't the entire MAF and you will need a special torx drive, I think it is called safety torx or something to replace the sensor.

I know a MAF sensor is cheaper than a fuel pump...

 

I'm from canada, I've looked everywhere.... Nissan dealerships, 627.99, refirished maf from a parts store with my discount, 249.99 with the core return, or a used one from a wreker, 150.00. I won't put a used maf in it, that's a waste of money, I won't order one offline incase. Its damaged when shipped ( being its such a delicate instrument, my option is the refuyrbished one and I'm fine with that! Lol, the fuel pump was 149.00 and has made a huge difference, but I still notice the hesitation... Yea I have the torx, its a t15 tamper proof torx its called. No I don't need the maf housing just the sensor it self, thanks for your input. When I'm not so broke ill buy a new maf and throw it in... Thanks foodmanry

 

Can anyone help me with removing the upper intake?

 

getflushed: You're sure that there were no codes? Not all codes put on the SES light (the knock sensor being one). Did anyone check the basic ignition timing? Is your warmed up idle in P or N around 700 and stable? And......no more additives of any kind.

 

Hey p. Samson-

Nope I've scanned it twice, once when warm and once when cold. I have no ses light or ghost codes. After the moto vac and fuel pump the all around performance feels a lot better! But the cold hesitation is still there, I reset the ecu and threw in a spare 2000 maf and it was the exact same. I'm pretty good with vehicles and I am stumped, I'm just going to have to wait for a ses light (if it ever comes on) I have done every possible thing that has to do with it running cold. Its seriously a bizarre issue... The only way I can describe it is, in "p" its like Hanging your rpms at 2000 for 2 seconds and slowly depressing till your at 1500 rpm its just like I'm backing off on the gas but I'm not! When its in "d" and I drive away cold its like I'm running out of gas... That's the best way I can explain it... Seriously, my fuel pressure is perfect, no vac leaks, no codes, no way of fixing this... That's how I see it now.
Again things replaced and cleaned are
Replaced air filter, fuel filter,plugs.
Replaced coolant temp sensor, cleaned maf and tested,tested tps, battery, alt.
Replaced fuel pump,intake gasket,tb gasket.
Cleaned throttle body and iacv.
Not burning/losing oil or coolant, tranny fluid is perfect..
. Its not missing, I know that for sure, its not compression, I haven't had timing checked, I guess I should but it starts up fine, idles good, when its warm its at about 800 rpm in "p" and yea about 700rpm in gear....

I don't know what else there is... .

 

Is this car stock as far as the engine goes, including the intake and vacuum hoses? Air ducting clamps are all snug? (in other words......no unmetered air is getting to the cylinders?) Your hot, no load idle seems a little high, but I'll see what mine actually is on my next drive. About the only thing I can think of, if you haven't changed it already, would be the PCV valve. After reconnecting the battery you are sure that you are giving it lots of time for the "relearn" before "testing" for the hesitation issue?

 

hey p samson,

I havent done the pvc hose.... probably should, it is completley stock including intake, ive checked all hoses and clamps, sprayed t.b. cleaner all over the hoses when it was cold and nothing, ( but like I said befor there was a tiny increase in RPM when I sprayed the egr funny enough there was no increase when cold only when hot kinda opposite of my problem hahaha, my mechanic said that its ok for a very very little leak there, he says hes seen it befor and seen other mechanic's replace egr's and gaskets to see that its still has the same very minor leak, he assured me that it was normal. i just dont understand how my idle is fine up to around 1500 and above 2000RPM its just in that small RPM range when cold it acts up, ill price out a pvc hose (im sure there cheap) and give it a go.

also, even though this mechanic said its normal for the egr to have a miniscule leak i've ordered gaskets for it anyways, so.... the egr has the black metal cap with the connector on top, below is the metal base with the two vac lines, where that metal base mounts to the (im assuming) exhaust manifold tube there are the three allen key screws, buy me loosening those off, will that allow me to dismount the egr from the manifold??? i have a feeling that is where the tiny leak is cuz it doesnt look like its seated right down on the mount.

thanks again for all your help with this p. samson anything else you could suggest would be great! keep the questions and suggestions coming!