NismoMaxm

Guys my maxima is pissing me off hahaha. Ok on friday i installed a new cattman cold air intake. Friday and saturday the car run like a fricken champ as it always has. Then today all of the sudden the car wants to run like crap. When i press down the gas pedal no matter what gear it bogs and barely comes out of it. Something is holding the car back and wont let it rev up and stuff. If i press the clutch and rev it up it will not rev up past 5 grand if 5 at all. My MAF cant be blwon because i took such good care in handling that plus if it was the car wouldnt turn over. I dont think the spark plugs have been chnaged and the car is pushin 80 thousand miles. i just had my oil changed too. and a new started was just put in. OK so it was very muggy and riany today aswell. When i press it to WOT or anything past slow rev it goes "buuuahhh" instead of "wahhhh" with increasing RPMS. The RPMS barely increase and the car literally feels like there is a rope attatched to it holding it back from accerleating. Any ideas?? PLEASE HELP ME!!

irish44j

iTrader: (38)

do you have all the vacuum lines hooked up and a good seal everywhere?

NismoMaxm

the only spots i plugged up where on my intake...tomorrow morning i will go out and plug up the vacuum lines.then i will let you know what happens, in fact ill go do that now...bbs with an answer.thanks irish.

NismoMaxm

ok irish the only one vaccum line that isnt hooked to anything is the one coming off the cams and main block. the one that comes off the right side of the top of the heads. all of the other little vaccum lines appear to be connected to something or eachother.. they may nto be hooked to the right things, is there a diagram for that stuff?what else could it be?



i also was thinking. Since my car just got a brand new intake put on, the plugs are old i believe, could the new intake run rich and foul out my plugs. A buddy said that could be one of the problem or the problem. I mean it ran perfect friday and sat all day, then this morning it just started to do all this bogging and rev nonsense. and the acceleration is jack squat due to the bog and rev. so hmmmm??

irish44j

iTrader: (38)

alot of people have found (as I did) that even if you are careful with the MAF,when you put a new intake on the increased vibration and airflow could cause a "weak" MAF to go bad quickly. Another thing you should check is to make sure the intake is secured (securely) and the bracket holding it (if there is one) has some rubber washers or something to reduce vibrations. Vibrations aren't liked by the MAF.

I had this problem when I first put my intake on, and replaced the MAF and made sure everything was as vibration-isolated as possible. No new problems after almost 2 years....

btw, the one loose hose is the crankcase breather tube...it is supposed to be loose....

I would get your hands on a new MAF (call DaveB) and replace it...see if it fixes the problem. If not, then you have a spare MAF for later, I suppose (I carry a spare at all times in my toolbox in the trunk)....

philthepain

All seems familiar to me. When I first road tested my max from the garage, I had..quote "Something is holding the car back and wont let it rev up and stuff".To fix that in my case the garage had to replace the MAF and 1 oxygen sensor.
Hope this helps.

NismoMaxm

rigth now the intake barely moves, like i mean the littelst amount. i may jsut take it into the shop tomorrow and see what they say since i know the guys pretty well. if they say something about plugs, ill get them to do it, if its an MAF i can do that myself i believe. I mean this intake is pretty damn stable. my old intake was worse than this. Also my cat is having problems and so is my muffler from frankencar. One side of the muffler is plugged up. Any possible connections??

NismoMaxm

any little bit helps man and i appreciate the help, all you guys are always helpful and thats why im so obsessed with my maxima and this website. cause no matter what i need to ask someone usually has an idea of whats going on. So well see what others say and what irish comes back with to my comment. thanks Phil.

-Marshall

irish44j

iTrader: (38)

I doubt your plugs would have suddenly gone bad to that extent.....really, my #1 suggestion would be to get a new MAF and switch it. That is the "most likely" problem, and a new MAF can be had for around $100.....

Not sure how the frankencar muffler could have one side plugged up thought

NismoMaxm

the packing fell down into one of the tips and plugged it. The packing is flaling apart inside of the muffler and my mechanice said it would be best to get a new rear section from them so i am. Plus its still going to be covered since ive only had the exhaust for 2 weeks.

nailz420

I see that you found the cause of the problem but

Since when does a blown MAF prevents your car from turning over? All it does is engage the fuel cut above 2400 rpms.

woosh

Meas the voltage on the MAF while you rev it past 3K it should put out more than ~2.57 - 2.8v. If it does not the MAF is dead/dying.

I will try looking up the pins and the approx voltage tomorrow

NismoMaxm

ok thank you, i do think my MAF is foobar because today i took some more time in looking over everything and stuff is all hooked up right,vacuum lines tight and plugged,seals are correct and when im reving it up the MAF kicks in and releases its wierd. Like ill be going along and ill punch the gas and itll make a SHHHHHHH noise and wont accelerate like it should. Im going today to buy a new MAF and should i install it myself or have a shop install it. Also i was reading that its recommended to get reprogrammed....good idea or not?? well basically is it necessary??

nailz420

Reprogramming is not necessary, i.e. it will work, but it's recommended (per TSB).

GBAUER

iTrader: (2)

It's not the MAF. I repeat: It's not the MAF. You said that you "plugged up the hole on your intake". I assume that it's the one between the MAF and the engine. Lemme guess: you also either plugged or put a filter on the valve cover on the right side of the engine? You need that tube between the intake and the valve cover. at WOT, the maf thinks that some of the air is being sucked away by the emmisions system. If it is not, the car will run lean. at that point the O2 sensors take over and really screw-up your a/f mixture. That causes the engine to basically drown itself or run so lean that you'll feel heat from the car when you get out (you probably won't see it on your temp gauge as the cooling systems on the max are very, very good, but you'll feel it because the exhaust is red-hot). You need that tube between the intake after the MAF to the valve cover. If not, you can burn your cat like I did.

BewstAdd1ct

at heavy loads vacuum leaks tend to be less signifigant. im thinking cat here...

check the engine with a vacuum gauge. the packing youre seeing int he muffler might not be the muffler packing... if you need to know how to run a vaccum test and ck the exhaust with it, let me know. if the check is okay, then start looking at the MAF...

GBAUER

iTrader: (2)

Or you can reconnect the hose as I mentioned above. If that doesn't fix it, disconnect the exhaust B-4 the cat and see if that does it. I swear I went through the same thing not more than two weeks ago. The cat was fried, but not that badly. Most of the problem was fixed when I reconnected the hose and allowed the computer to remap the A/F ratio.

BewstAdd1ct

yes, reconnect the hose and run a vacuum test. you can check the entire exhaust system without getting your hands dirty.

NismoMaxm

ok when i get the car back from the shop i shall reconncet that hose. but then why can some people run a breather and be fine when my hose is just basically free. i didnt plug up the valve cover hose, i just left it open,i repeat the hose isnt plugged to the intake but is just free.

BewstAdd1ct

before, the MAF sensor was getting metered air, now its not. itll throw the maf off at idle, under load its not a big deal, it certainly wont keep you from revving over 5K.

check the cat, then the MAF.

NismoMaxm

yeah i was alil off about the reving over 5k, itll rev over 5 k it just takes alot i mean alot of gas pedal pressing to get it there. the acceleration is way off and is very boggy then clears ever so slightly then bogs again. the guy at the dealership thinks im heading up the right tree as far as the blown MAF goes. But we will see.

GBAUER

iTrader: (2)

That's not true at all. The MAF is BEFORE the hose that goes from the intake to the valve cover. When you mash the gas, the maf expects a certain percentage of air to enter the valve cover and a larger percentage to enter the combustion chamber. If you instead allow all the air to enter the combustion chamber and none to enter the valve cover, the engine will first run lean, then the O2 sensors will detect an abundance of O2 in the exhaust, the computer will try to compensate by turning up the fuel, the engine will now run rich and bog itself down, let out un-combusted fuel into the exhaust (causing problems with the cat), gum up your valves and fry your plugs.

NismoMaxm

so i should reconnect that hose to my cattman intake asap. but its in the shop.

NismoMaxm

ok the guy at the shop told me its just a breather opening and the need to plug it up the the intake isnt what is causing my problem. I unplugged my MAF and moved the car and it ran more like **** then it does as is. The bogging was ten times worse. So my MAF may not be tottaly ****ed but is def. a posibility from the looks. the shhhh noise got even worse and the car would barely accelerate with the MAF unplugged. Also my cat is tottaly fubar so he said it may be restricting air causeing it to screw up aswell. Any insights??

BewstAdd1ct

the shhh? is it hissing form the exhaust? seriously, do a vacuum test.

um, ya.. i know. thx maybe i misworded my post... all the air was metered before, now its not.

when you mash the gas (WOT), none of the air is going ot the valve cover/PCV system. and a MAF isnt looking for percentage, the voltage reading is converted to mass, usually in g/s, kg/min, etc.

not lean enough to keep the car from bogging, and when it adds fuel, it only matches the extra air. why would the fuel strategy make it run overly rich? you can create a small vacuum leak, and if the trims are under 10%, you can still have stoich. not ideal for cold start an throttle response, but by no means going to 'fry the plugs'

over time, you might see an issue develop. i still think the problem is in his cat, im just waiting on vacuum test results.

GBAUER

iTrader: (2)

Just do me a favor and plug the stupid hose back in like it's supposed to be. Try it and I can guarentee that it'll perform much, much better. I swear I just went through this. Your mechanic may be a nice, great guy and all, but he hasn't seen this before. I have. If you don't want to listen, well, I'm done trying to tell you how to fix it in five minutes for free.

BewstAdd1ct

^^^ seriously. plug the damn hose back in.

NismoMaxm

ok ill go plug it in right now.

ok 800 pm i plugged in the hose and the car runs the saem as it did before i plugged it in. The hissing is coming from the filter or intake itself. it sounds like its coming from somewhere along the intake path. whether it be the filter of maf area but its definitely coming from there. i plugged in the hose now all the vaccum lines are right and i oredered a new cat and it will be here tomorrow. any more help would be appreciated. jsut ask me quetions and i will respond with as much detail as possible. thank you everyone.

BewstAdd1ct

hissing from the intake is pretty much normal with an aftermarket pipe, should sound like its coming from the filter.

did you run a vacuum test?

2000maxixam

replace your maf...i had the same problem and it fixed it instantly

NismoMaxm

bew, this hissing isnt normal hahaha i mean its like shhhhhhhh not the typical aftermarket hiss coming from and intake. i do believe my MAF is messed up so im going to replace it tomorrow. i cant run a vacuum test cause i dont have the necessary stuff.

BewstAdd1ct

a vacuum gauge?

go to pep boys/a/z and buy one...

NismoMaxm

lets just put it this way man, until sunday, two days after i put oin my intake not even two days i got this lagging issue and acceleration problem. Before everything was just fine. last time an intake was put on this car was by the previous owner and he had to get a new mAF aswell. So i think that if the new MAF doesnt fix it then ill do a vacuum test. do you think thats a good idea?? maybe my dad has a vaccum gauge. how do i use it?? plus my gas mileage is shot like badly. that help any??

BewstAdd1ct

a vacuum test is free, i just suggested it before you replace any parts.

you connect it via a vacuum line to manifold vacuum, checking for an exhaust restriction would entail revving the engine to 2500 and holding it there. vacuum should drop initially (upon tip-in) and climb to 15" or more (18"+)

if after holding it at 2500 for a couple seconds, it drops back down to 10" or lower, youve got a restriction...

im sure theres a site that can give an example of vacuum gauge readings. if youve got the time.

NismoMaxm

ok well ill ask the shop to do a vacuum test which i think they were planning on doing nayways. I mean i dont have any ways of getting out to pep boys or anything because my car....im not driving it until its fixed cause im scared to scrwe it up or blow something worse then just and MAF or something small.

NismoMaxm

so today i went and bought the new MAF......threw it on there, connected all the hoses...and the fricken car is still runnin like crap. My cat is officially gone sour. Im thinking maybe the shhhhhh noise is that the air is being pushed back out of my intake due to back up in the exhaust maybe??gonnah ave a vacuum test done, MAF vlots check thing and such, spark plugs checked and exhaust cheked tomorrow. any other ideas??

BewstAdd1ct

the following is my first post in this thread.

or maybe i should just change my sig to "OMGzz ITSS YOUR MAFFFF"

NismoMaxm

take it easy man im not a car god. and IM BROKE. plus i cant get out there cause my car isnt very safe to drive because i cant move out of the way of anything cause when i hit the gas alil it bogs around 2 plus grand. so this is my last question.... So i should get the vacuum test? and you think its my cat??



thanks for everything dude.

GBAUER

iTrader: (2)

Try resetting the computer. Read the stickies for the procedure. Your air/fuel ratio is still screwed up in the computer.

NismoMaxm

which sticky am i looking through?the TSB or check engine light. I dont have the power to search here on the forum. But im gonna try google.