ConcordMaxi

So ive got a 1997 maxima se. Im in total love with the car but just cant figure out my problem. No engine codes apear. Car is at 226000 KM.

SYMPTOMS (symptoms are intermitent)

-Car bogs at seemingly random times under 4500 rpm
-When car is at idle the bog is usually enough to cause the car to die completely
-Car has been harder and harder to start
- Obvious loss of power under 4500
-Car seems to run better when i hold at high rpm for a second or two.
-If i have the car in neutral and regulate rpm with the throttle it doesnt die but will still bog
-when bogging at iddle oil pressure light somtimes comes on until gas is applied and rpm rise.
-Black paint coating on sone coils have been damaged

ATTEMPTS TO FIX

-Vacuum leaks have been ruled out.
-Injector cleaner has been run through the system
- spark plugs are oxidized and will be changed very soon but i dont see this being the only issue
-mass airflow sensor seems to be working fine
-I doubt the cats are clogged as when it does run ok it has normal power across the board
-Battery recently swapped
-Throttle body is quite black past the airflow valve but from the valve to the airflow sensor is perfectly clean. Im not sure if its necessary to clean.

Im strongly leaning toward just replacing the coils and spark plugs but i dont want to spend on the coils if i dont need to.

PH98I30

Its hard to tell without a code to read. It could be your fuel filter or fuel pressure regulator. Usually a bad coil pack just makes the car idle rough with a little loss of power when accelerating. Could still be a bad MAF. Get a spare at a junkyard... they are pretty cheap there.
Others chime in please......

ConcordMaxi

yes i planned on changing the fuel filter regardless. Also i should mention i can feel what feels like a misfire at idle but still doesnt pop up a code. When i unplug the MAF the car shoots like 5 engine codes at me and when i plug back in and clear codes they dont come back.

DennisMik

iTrader: (2)

It could still be the MAF. The MAF is notorious for not throwing a code. Probably 75% of the time it doesn't throw a code. Unplugging the MAF will cause codes because the monitoring circuit is broken.

Unfortunately, replacing the MAF is about the only way you can rule it out. That's why people recommend a junkyard visit.

maxgtr2000

iTrader: (29)

Spark plugs should definitely be changed and then go from there. Cheapest things first.

JoshG

I had a misfire issue and bogging as well on idle. I was told it was the mass-airflow sensor and what not.. turned out to be the coils.

Bought a brand new set of 6 Hitachi coils for $280 or so. Never had a problem for almost 2 years now with bogging/misfire issues. Make sure you get Hitachi otherwise the problem will still occur..

ConcordMaxi

Well ive got 6 new platinum plugs on the way along with a fuel filter so lets hope its a cheap fix this time lol

CS_AR

Regardless of the outcome, your Max is at the age and mileage where you should think about an injector service consisting or o-rings, pintle caps, and screens. Consider a fuel pressure regulator in the same operation. You'll save yourself a lot of headaches if nip the injector leaking issue in the bud.

ConcordMaxi

How much is that service going to run me? In CAD preferably if possible

JoshG

Usually $100-200 for injector rebuild..atleast from what I heard.

CS_AR

If you are handy you can refurbish your own. There is a kit I buy from eBay. Named CS performance injectors. I usually get 2 sets of 2 or one for an 8 cylinder to have spares.