This started yesterday. I came home from work then after left the house. Put car in drive to drive off and it immediately jerked forward and backward like if you let go of the clutch fast in a manual transmission. When I went on freeway it did that from 30-45 mph. Today when I drove off it started doing that at 30mph again then the check engine light came on. I stopped to turn at a red light and car turned off! I turned it on and drove home. Went to aamco, me and guy went to test drive it and they got airflow and knock sensors when he checked the cpu but wouldn't give me the rest of the story and said they gotta scope the entire car for two hours to find some things. The man said he doesn't think its transmission problem. I would like to know what's really up with it before I go spend the 149 for the check up tomorrow. When I popped hood I can hear a hissing sound but I can't find it. 98 maxima automatic. I also disconnected the MAF to test it but the car wouldn't go past 2000 rpms without it connected. I drove it connected and it could accelerate past 3 or 4k what can be the problem?

 

It really sounds like the MAF is failing. A lot of people have had really similar symptoms which a new MAF fixed.

 

It is not transmission, most likely is the engine, many things can cause this, clean MAF, throttle body, check vacuum leaks, O2 sensors, EGR tube, etc.. Pull the codes first, autozone should be able to do that for you for free.

 

Check the accordion-type hose that connects from the MAF to the Throttle Body. I'll bet you a beer that there is a crack in it that opens up when the engine rocks and it is letting in false/un-metered air into the engine and the car is running lean, and then it slows down, and closes the crack, and it bounces back and forth.

E-mail me the virtual beer ! I remember the 1st time I discovered this issue on my daughter's MX-6, and I thought I was a genius to figure it out. Hope I'm right !

 

Unmetered air aka maverick air, buy a cheap 5-10 vacuum gauge and its pretty easy to test for or it could easily be a dirty injector or failing coil causing a random misfire in one of your cylinders aswell but from the hiss you mentioned i would search around for old cracked hoses first before i did anything.

 

sounds like a bad MAF. A misfiring will cause a slight hesitation or stumble. Bad MAF will have your car bucking like a bronco!

 

Man the 2 things that happened to you are the same exact things that happened to me with a bad MAF. Car shuts off slowing to a red light, and stumbling at around 40 mph. I pulled a code P0100, replaced the MAF, problem fixed.

 

and also please use OEM MAF please. Aftermarket will screw it up.

you would be surprised how many people would get a problem like this and has no idea what it is other than saying "OMG THE ENGINE IS DEAD TIME TO GET RID OF IT"

 

+1

I've read the reason OEMs work better is because they are made by the same company that makes the ECU. Beware of cheap imitations. I usually pick up used MAFs from a junk yard. As soon as I get the MAF home, I clean and test it then keep it in the workshop as a spare. Usually every other MAF that I get from a junk yard has to be returned. I've pulled some bad MAFs from some decent looking 4th gens in the junk yard. I wonder if the previous owner (or dealer) couldn't figure out the MAF was failing and just gave up and sold the car to the salvage yard.

Courtesy Parts has some good prices on OEM parts www.courtesyparts.com.

 

Well, I definitely need a knock sensor. Mine is cracked. My personal mechanic looked at the Maf and said it was good and clean. He couldn't get the knock sensor out the fast way, so now to take intake off. But for 120$ instead of 300$ labor and 200 for the part since they always order from autozone. Oreily had it for 104.99. Idk. If it's not knock sensor than its maybe something else. These other mechanics don't even like showing you what the code reader says. So I don't understand the "we will check your check engine light for free" means. It should also include, "but we won't show you the codes"

 

But my MAF is working. But my knock sensor is really cracked though. Hope that fixes it. The car now doesn't studder since the sensor doesn't work. But idk

 

Usually a failing KS will not cause a studder or misfire like a MAF problem.

Is yours a California model?

I have always been able to remove the KS by using a 1/4 inch drive U-joint (wobble joint) with a 10-12" extension. The 1/4 inch drive will support a tighter angle operation. To install the KS, I get someone with small hands to reach under the intake manifold to get the bolt started.

 

a bad knock sensor WILL reduce your performance and the way the car runs, if u have a proper working knock sensor the car will run a heck alot better compared to a bad knock sensor. but if u have a bad one, it wont effect the car running in anyway, just its performance is worse.

I have heard people use ebay knock sensors and it lasted them years, but im pretty sure OEM would be nice too.

and yes if you picked up a decent looking 4th gen and its MAF was bad, guess you know it they got rid of it cause of one simple thing that caused them to get rid of it.

 

The same thing has been happening to me the last couple of days on my '99. I pulled the codes at Autozonoe and got P0160. Possible oxygen sensor defective or system running very rich or lean or the fuel pressure is very high/low.

I replaced the fuel filter and the problem continued a day later (last night). I also had code P0325 which is a knock sensor which would suggest low fuel pressure as well according the the code printout.

I want to know if the knock sensor really did fix this guy's car.

I'm going in later for a diagnostic.

The courtesyparts.com site offered earlier is extremely expensive= $450 for a MAF. Called NAPA and they said $250. Want to be sure i buy the right part so I'm not just replacing parts. I'm curious about everyone who said they replaced the MAF- did you actually see the MAF was defective or did you have a diagnostic run and they said it was the MAF?

 

The role of the Knock Sensor is to suppress the aggressive power of the engine long enough to get someplace safe without damaging the engine further if it detects something that causes a knock.

The ECU controls the throttling back the system when the Knock Sensor tells it to.

This is a completely different response. However, a bad knock sensor can be combined with other things like the already mentioned, MAF.

I'm not sure if it's all 99's or the second half of 99's, but changing out the Knock Sensor meant removing the top to get access. I figured out how to get the old one out, but there was no way to get the new one in and threaded. An overdose of Windshield Smashing Frustration!

Good luck Fellas!

 

OK, I got back from Nissan and they confirmed I needed a MAF. They also said there's a chance the CAT is plugged. That possibility scares me. I'm going to get an after market part from Napa as it's half the price yet carries a warranty, and have a local mechanic put it in with a new air filter- which i need anyway but am told is needed at same time of replacement. The whole process should take less than an hour.

 

The OEM is just too expensive. Over $500. I'm hoping the rebuilt one works fine. I've had rebuilt alternators work fine on some past projects so why not a sensor??

 

Let us know how the Napa MAF works out.

I had clogged/cooked cats last year that made the car hard to start. To determine I had a clogged cat problem, I removed the O2 sensors so the engine could breathe and started the car. While it was on the loud side, it ran better with the O2 sensors removed (while leaving them plugged in) and it was easier to start.

Depending on your location, you might want to consider a Y-pipe if your cats are clogged. Last year I installed a WarpspeedPerformance Y-Pipe to remedy my cat problem and the car gained horsepower and performance. The Y-pipe was the biggest performance bang for the buck that I've experienced on the Maxima to date.

 

What happened to JLA117's problem ? Somehow this thread got jacked.

 

His mechanic is replacing his Knock Sensor because it appears to be cracked.

 

Of all the Big Chain Auto Parts places, I've had the best luck with NAPA consistently.

Please do report back on how well the car and the NAPA MAF play nice together. So many of us will be having to address that somewhere along the way, probably sooner than later.

Might save a lot of us some big coin!

Good luck!

 

every time i see this thread title all i see is "maxima jerking off"

 

For my sake I hope everything works out.

 

The guy said the knock sensor could cause the Maf to fail but idk how. My maf is fine unless I should insist on changing it. Aamco guy told me air flow sensor and knock sensors. I hope he's not lying and it's another different one. I don't like seeing my service engine soon light on. Tonight car drive very good but it shut off in two stop signs. My stock maxima keeps up with my friends 2014 frs! 190hp at 3085lb vs 200hp 2750 lb. Idk about now with the problems though. So insist to change Maf? Oreiley sells it for 200$. And I'll do it myself. I got no one with small hands to take knock sensor out. Why do they put that sensor in there for? Couldnt they have put it like 6 inches more towards the battery? More labor.

 

I don't know how to tell if it's a California model. It's maybe been an Arizona car for 200,000 miles already. I got this car with rebuilt transmission and supposedly engine too but I'm missing the engine work receipts.

 

Haha that's what I just noticed. I should of put maxima studdering

 

Here's info on how to determine if you Maxima was built for California.

https://maxima.org/forums/4th-genera...tml#post707273

So how do I tell if my car is Cali or Fed spec?

Raise your hood. Look for a shiny metal identification tag fastened to the passenger side of firewall. The top row is the Vehicle Identification Number, starting with J. The second row is model information. The first five characters are BLHUL. The 12th character is the destination:

N = Canada
V = California
U = US, not California

 

First, a Knock Sensor code is known as a ghost code. It often accompanies or follows other codes. When the other code has been resolved, the Knock Sensor code will often disappear.

If you are receiving a code for a MAF problem, the Knock Sensor code may have been triggered by the MAF code. I would fix the MAF problem and check to see if the Knock Sensor code goes away. That is if the MAF is displaying a code in the first place. Do you know someone that has a code reader that can display and reset the codes?

Here's a thread for how to read and reset codes in the link below without using a code reading tool.

https://maxima.org/forums/4th-genera...ere-first.html

Also note that I've seen people buy low cost code reader reset tools in the $20 to $50 dollar range. I bought one of my scanners at Harbor Freight for $49. I see that same scanner being sold at www.Tmart.com for $17 and change. Parts stores sell low cost scanners.

When my MAF failed, the car would die at stoplights unless I kept my foot on the accelerator and brake at the same time to keep it running.

 

For MAF, I went to cheap eBay one, I think it was around $50, 4 years already, works just fine, but last time I went to junk yard to pull a front wheel hub, I got a OE MAF too as spare, still in my garage.

Your MAF could be just dirty so before you commit to buy a MAF, try to clean it with CRC MAF cleaner, give it a really good spray, let it dry for 30 minutes before re-install, clear the code and drive for like 200 miles to see if the codes come back.

 

Trust us, it's not the Knock Sensor. The Knock Sensor code is often a piggyback code the the real issue. In your case, the MAF. Get a new MAF, clear codes, and I'm willing to bet your driveability issue will be gone. Now, you may still get the Knock Sensor code because you state it's cracked, but that's a maybe, and not worth the hassle of replacing at this point in time. At least your Max will drive nicely again.

If and when you do the Knock Sensor, you can get that for $10-$15 shipped on Ebay.

 

I went to autozone to see one of their scanners. They out it in the system and now it's just the sensor under the intake he said. Now it's one. I already scheduled to just fix the knock sensor. So if it is the Maf I can do that myself in future. That one looks super easy but that part alone costs 200. I'll clean Maf first

 

doesnt the 10-15$ knock sensor tend to break quicker than OEM? and somtimes dont work as well? i have one from ebay, but i dropped it by accident on the road maybe 2 feet from ground. dont know if its still good after dropping it once.. cause i heard they're sensitive.

 

KS alone won't turn on SES light on, MAF does, like others said, KS code is just a piggyback to other codes.

Search here, there some good DIY KS replacement thread, youtube also have KS replacement videos, you do not need to take intake manifold out to do this job!
http://youtu.be/R2ntaxi7bXk
http://youtu.be/fPIMOIwLISc
http://youtu.be/rj1pQtQoAuo

 

just get a oem MAF from the junkyard and clean it and put it on yourself. your throwing away money.

 

I wish Arizona had good junk yards. California had the best ones

 

I've never read or heard this. The Ebay KS gets good reviews around here.

And it goes w/o saying, don't drop them.

True, but the manifold does have to come off on the 99 CA spec Maximas.

 

If you're not going to take the advice of many, why bother asking for help?

Do what you want, it's your Max and your money. But believe me, we know the ins and outs of the Maxima better than any mechanic or store employee that you've talked to.

 

I tried to help the owner determine if the car was a CA spec model to no avail. Ok CIAO..

 

The OP asked questions but never take the advices, I guess the OP is not a DIYer so I think he just want to make sure that paying someone fixing his car is justified.

So all I can say is good luck.

 

So Potentially the one i have dropped only once is already bad? i gotta install it soon .. but doing my other big project to the car. almost done with it!