Just started yesterday; I punched it to make a light and car started to shake and it felt and sounded like it was running on 5 cylinders. No power uphill. Let it idle for about 15 minutes and it was fine. Took it to work this morning, started out fine then about halfway to work it started acting the same way as yesterday. No CEL!!!! Waddya think??

Joe

 

Misfire? Coils? MAF? Fuel issue?

Gotta troubleshoot

 

Yeah, I know. Haven't had a chance yet. I thought I would throw it out there to see if I could get some ideas. Usually when a coil pack goes, the CEL will light. I have to use my code reader and see if there are any hidden codes.

 

Not true, the ECU cannot see if the high voltage side fails/opens.
Both cam sensors can also detect a misfire by measuring the timing between cylinders, but it takes a while for that to register.

 

Agreed. What year max do you have OP? Still the 95 as listed?

Check for the obvious KS code (it won't trip the CEL) too.

 

Not entirely correct, at least not in all cases. Some vehicles use the primary winding to measure the collapse of the field in the secondary winding. You can also see this with an oscilloscope. This will tell you if there is a break or short in the secondary winding.

 

Yes, still have the 95 Max; just turned 191,000 miles this morning!!!! I finally had a chance to use my code reader on it yesterday and it called out the P0325, knock sensor. Car is still running fine and no CEL. Could that code be caused by using lower octane fuel??

 

If you're getting nothing but the P0325 cel code then change that knock sensor. Your engine will run much smoother. I inserted a high priced OEM knock sensor 6 years ago but if you want to save money then buy one off ebay. I've read on this forum that those ebay knock sensors perform well.

Running regular fuel in your engine is what wrecked the knock sensor. The higher octane gas you use the longer that knock sensor will last. Our manuals suggest using only premium gas.

 

Car is running smooth. I've been using regular unleaded since I owned the car back in '97. Can't afford premium!!!

 

Fuel injector

 

Replace KS, and start using 89 if you can't afford 91. Will only set you back an additional $2.00 per fill-up.

And make sure your car is in tip top shape. Good air filter, fuel filter, clean oil, good PCV valve, good coolant, clean TB, clean IACV etc etc. All these things will help give you the best mileage possible.

 

Really?????

I have owned 3 maximas and and tried 87 with each. The car would run so sluggish and slow. I always put 89 or better.

 

unless your driving with a 50 gallon tank, just use premium anyways. Like the Wiz said, there is only literally $3 difference on a FULL tank of gas and your getting better performance, better milage, and a piece of mind. Not to mention your manuel calls for it. You CAN afford premium.

 

if cost is your highest priority buy a Camry or Corolla.

 

Or start hitchhiking...or riding a bike... j/k

 

Hope you learned your lesson - and that lesson is: Don't EVER admit to using regular 87 octane gas in your Maxima on this forum!!! Some of these folks are fanatics on the subject!! But know - you are not alone!!

 

Last night, I thought I found a bad coil pack. I unplugged the front coil pack closest to the battery and nothing happened. That made me think it was bad. I swapped that coil pack with the center one, unplugged the center coil pack and it made a difference in the engine. So now I'm not sure if it's the coil pack. I removed all front coil packs, tightened spark plugs and reinstalled coil packs with a little dab of dielectric grease. Couldn't meter the coil packs cause I didn't know what pins to use since the picture in my Haynes manual didn't match what I have. Cleaned the MAF sensor, started the car and it ran fine. Cleared all codes. This morning, car acted up again. Wasn't idling right and when I gave it the gas, it was stuttering. Didn't have a choice but to drive it to work. As the engine warmed, that car ran fine. As I got closer to work, the car started hesitating again. I searched this forum for "knock sensor" and I'm not sure if these symptoms are related. If a knock sensor is failing, can it be affected by engine temp??