During my last autox event, which was on a track, i thought i was running out of gas. i had a 1/4 tank, but it felt exactly like running too low on fuel.

so i filled up when i left, and i get the same situation on the interstate, etc... from about 3500 to 5500, it feels like i suddenly am pulling a trailer, and when i hit 5500 it feels like i hit vtec hahaha.

(EDIT: also, while accelerating in high gear at low speeds (i.e. 4th/5th gear at 35-45), it bucks INSANELY bad.)

while at idle, it sounds like i'm missing. or running out of gas.

so, knowing that it had to be one of 4 things (fuel, air, spark, compression), i start to narrow it down.

i have NGK iridiums that are ~1 year old. not spark.
i don't know why it would be compression, so... not compression.
i have a newish filter on, so i suspected a bad MAF and replaced it. didn't fix it. not air.
i can only assume fuel, unless i missed something. i have a Z32 fuel filter, and stock everything else. AFAIK, nothing else has been replaced. i have had the car since 2007 and have never touched the fuel system. it's been cleaned a few times, though.

so here's the question: injectors, pump, dirty tank, or what? or did i miss something else?

thanks in advance!
tyler

 

run some chevron techron fuel injector cleaner and chevron fuel and see if it clears up if not then its not injector, by that time check engine light should come on and tell you exactly which cylnder is missing and then replace that cyls ignition coil.


try that may help.

 

thanks dude, but the fuel system has been cleaned. i use iso-heet every month (it's the winter stuff that doubles as summertime injector cleaner) and i run nothing but 93 octane. however, the knock sensor is shooting a code. has been for a year, so most likely unrelated since my problem just started.

 

fuel pressure regulator? just throwing something out there

 

It is your coils. I am having the same issue as you now and the coils are failing under load. If you put it in neutral, you will not feel the bucking at idle at all. One of your coil(s) is dying but not enough for it to register on the ECU. Start saving and start replacing one by one...start with the ones at the back.

 

coils sound like the most probable thing listed so far i had a coil failing for like 2 months but no bucking just a cel flashing at me, i been told thats the motor misfiring in real time. but i also have a nasty 92 foxbody but it wasnt nasty when i got it lots of parts but ran like poo wouldnt stay on no matter what and the bucking oh man it made the two words mustang and bucking well you get the idea but i was told cam fpr ignition everything. it ended up being a gasket was used by the previous owner on the lower manifold that the instructions said to leave out and use rtv. short story i tore a perfectly good 5.0 down to pistions for no good reason check you vacumm lines and then check them again and then get a torch unlit and move it around suspects with the engine running and listen to the rpms they go up when you get close theres a leak

 

thats what mine did it was the ks

 

I had the same problem and it turned out to be faulty grounds. i replaced and upgraded to STILLEN Grounding Kit, runs better than ever. and thats saying alot because i have over 175,000mi

 

Mine just started acting up today after filling up. Can't get her above 2500 rpm when I have bucking and like the fuel is cutting out. I have 263K on it and have never replaced the fuel pump or really anything fuel related besides the fuel filter. Do you think either of those could be the issue or something else.

 

This. I have been waiting for a year for CEL to trip, and still nothing

 

MAF.

 

Is there anything for these cars to monitor the sensors? My husband owns a dsm and has the capabilities to monitor the sensors using a program he downloaded onto a laptop and plugging it into the cars computer.

 

I got my cousin to ship me up an OEM set (Hanshin's) from Florida and replaced all of them and the problem disappeared. He got them for $20. Couldn't go wrong..

 

Its your coils. The EGR vavle on maximas cause the coils to fail over time. Do what I did. I blocked off the two hoses going into the intake manifold for the EGR. Do that and change your coils. Then go to radioshak and pick up a 470k OHM resistor and put it in place of your knock sensor. There is also a hose going to your valve cover to the intake manifold block that off also. I have did this to my car since it had 240,000 miles and I now have 283,000 and still running strong.

Injectors go out also if you never change the fuel filter. You can check the OHMS on the front 3 but I doubt this is your problem.

Also don't buy ebay replacement coil packs. They suck. Get new ones with warrenty or go to the junk yard and OHM test them and if they are good throw them in.

 

This info is misguiding...how could those hoses and the EGR system cause the coils to fail over time? My original Mitsubishi's went out at 303K..

 

My plugs got fouled up over time when i ran the car hard. When i pluged up those hoses it felt like egr was disabled and WOT power increased a lot and the coil packs never went out. Also check your grounds. My plugs never get dirty now and at idle it purs. On the left side of the IM there is a hose going into the valve cover. Not sure what it does but it was sucking oil and fouling up the rear left cyclinder. I blocked that up and the car runs good.

 

The EGR system gets really dirty over time. Thats why you have to clean the tube but also the intake manifold gets really dirty. I cleaned mine out and the IACV and blocked those hoses off and my car flys and all I have is a Y pipe 5 speed and the 470k ohm resistor because im too poor and lazy to fix the ks properly..lol but I can only use 93 octane and 89 sometimes when its super cold and im not driving hard.

Dirty plugs makes the coils work harder and eventually they go out.

 

Your MAF sensor is getting ready to go. If the symptoms are correct you will soon get a code for lean or rich in one or both banks.

Except in my case I got the lean code first and then came the symptoms.

An easy way to test is while your car is sputtering at idle, unplug your MAF. Just simply taking out the connector should do the job. And if your car stabilizes then your only problem is the MAF. But if you are still experiencing the same problems after the MAF is disconnected it is not the MAF.

 

I'm having the bucking problem as well on my 2000 Maxima. I replaced the coils and plugs after a series of multiple misfires. I am having issues at the moment if someone can help. I get some bucking at around 2500 rpms and my car doesn't start without the "two-foot method"