i am a happy owner of a 2k se. however a friend of mine has a 99 se that he has problems with. please tell me if any of you know of or have experienced any of these problems....occasionaly when he starts his car it taps real bad. then when he drives it almost sounds like a queit diesel. he says it reminds him of when his motor mounts went bad in another car, but he isnt sure. now i asked him if it was only when the car was cold. he says that it will start up sometimes fine and it will run good, then all of a sudden it will start as he is driving down the highway. does anyone have any ideas? the dealer says they cant figure it out. and get this....this is the 4th time he has brought it in and they gave him a geo metro as a rental. kind of embarrasing. any help would e greatly appreciated

 

I realize you are getting this story second hand, but more information would be helpful.

Did the Service Engine Soon light ever go on?
Did the dealer do a Diagnostic Trouble Code readout?
Did the dealer test or replace any sensors in an attempt to resolve the problem?
Does your friend fuel his Maxima with 91 AKI (or better) gasoline?
Is the sound louder when the engine is under load (accelerating or climbing a hill)?
Are there any other symptoms which might be related to this problem?
Has the car ever been in a crash?

 

just a shot in the dark .. would a fuel filter cause some of those probs?

 

Good thought. An obstructed fuel filter could result in below-spec fuel rail pressure...
which could result in a lean fuel mixture ...
which could result in pinging so severe that the Knock Sensor couldn't cope with it. Fuel pressure is not monitored by the Engine Control Module, so low fuel pressure will not (directly) cause the Service Engine Soon light to go on.

Low fuel pressure could also result from a weak fuel pump or a defective fuel pressure regulator.

 

Dude,
I'm a happy owner of a '99 Maxima. But i haven't experienced the problems that are happening to your friends car, but i have other problems, like the car has a hard time starting every so often. My fiance and i have taken the car back to the dealer a couple of times, and just like your friend, they found nothing wrong w/ the car. I'm also curious if anyone else has had these problems.

 

sometimes the hardest problems are solved with things we overlook ...

 

No problems.....wwwooooooooooooossshhhh, thank god.

 

No problems here either, except for an aftermarket sunroof the previous owner installed which rattles over bumps.

 

Sometimes my 99 will tick when I start it after letting it sit for several days (yes, I'm using Nissan oil filters). I dismiss it as simply a hydraulic valvetrain component that has drained back, although I'm not sure.

Lately, however, I've noticed a slight tick even after the car is warm. It seems to be coming from the rt side lower part of the engine, but it's too hard to be sure. It's no way loud enuf to hear inside the car, but outside, it's def there. I've heard it on other 4th gens, but it didn't seem to be as loud. Could just be my imagination. Everything else is fine.

 

Our 4Gen engine does not have hydraulic valve lifters.

It is important to identify the source of the noise. A four-foot length of small diameter rubber vacuum hose will help you do this. You can buy the hose in any auto parts store. They typically sell it in bulk for about US$0.50 per foot. Start the engine and let it idle. Put one end of the hose in your ear and the other end near any suspected source of noise. The engine compartment presents a cacophony of sound. The benefit of the hose
is that it isolates the sound from one specific area.

You may find it interesting to explore the sounds of your engine with this inexpensive tool. Each moving part has its own characteristic sound. For example, listen to the muted clicking of the fuel injectors. They should all sound alike. If you find one with a different sound (or no sound at all) you have found a problem.

The dealer's service department is equipped with high-tech diagnostic instruments. These are wonderful devices but they are expensive and the dealer has to recover his cost by charging you for diagnostic time. Sometimes the home mechanic can do legitimate diagnostic work with nothing more than a rubber tube.

Work safely! Take care to avoid contact with any moving parts such as accessory drive belts.

Enjoy the ride!

 

You say 'every so often', chances are that is when you are below 1/4 of a tank of gas and/or it's really cold outside. The solution to this ( my personal experience ) is to always 1) prime the fuel pump before starting the vehicle, and 2) always keep gas tank at least 1/2 full and use a minimum 91.

Since most gas stations offer 87, 89, 93; just use 93 to fill it up all the way, then when your at half tank fill it up with 89.

In order to prime the fuel pump all you have to do is after the key is in the ignition, turn it two notches; you'll hear beeps and interior lights will turn on. Wait about 10-15 seconds, then proceed to turn it to the third notch which will start the car. Priming the fuel pump sends fuel to the engine and this pressure will in turn start the car smoother. Priming the fuel pump should be done on all makes and models of all cars, it's just one of those simple things that helps the car out in the long run.

(This is how it was explained to me, so if any of this is sketchy, or prehaps innaccurate please respond with more accurate information; but whatever priming the fuel pump actually does, it works)


You'll notice that if your low on gas it will not want to start as easy, this is because there is not as much pressure applied, where as if you have a full tank of gas; more pressure, easier start.
Note: My personal Opinion that you should always keep at least 1/2 tank in your car, and run it down to the empty light once every month or two.

-Nate

 

can be caused by low oil or no oil. when the oil is low, the engine can act and sound like a diesel. shaking and losing power. but the dealer could of figured that out. i would take it to a QUALIFIED mechanic. im out.

 

I respectfully disagree.

When your engine is running the fuel rail pressure should stay in the 34 - 43 psi range. When your engine is switched off that pressure should be maintained. This is called residual pressure. If your engine starts readily after the 10-second delay (but not otherwise) your engine may be losing its residual pressure. This is a sign of a fuel leak, external or internal.

An external leak is one which allows the fuel to escape from the fuel system. It might be caused by
- a leaky rubber fuel line which allows fuel to escape into the atmosphere
- a sticking fuel injector which allows fuel to escape into the intake manifold

An internal leak is one which allows the fuel to escape from the fuel rail back into the fuel tank. It might be caused by
- a faulty fuel pump check valve
- a bad fuel pressure regulator

 

[QUOTE]Originally posted by nforg
[I]The solution to this ( my personal experience ) is to always 1) prime the fuel pump before starting the vehicle, and 2) always keep gas tank at least 1/2 full and use a minimum 91.



In order to prime the fuel pump all you have to do is after the key is in the ignition, turn it two notches; you'll hear beeps and interior lights will turn on. Wait about 10-15 seconds, then proceed to turn it to the third notch which will start the car. Priming the fuel pump sends fuel to the engine and this pressure will in turn start the car smoother. Priming the fuel pump should be done on all makes and models of all cars, it's just one of those simple things that helps the car out in the long run.

Every time you turn the key over, the fuel pump is always turned on and it,s only for about a second and then it cut,s off and waits for you to start.

(

You'll notice that if your low on gas it will not want to start as easy, this is because there is not as much pressure applied, where as if you have a full tank of gas; more pressure, easier start.
Note: My personal Opinion that you should always keep at least 1/2 tank in your car, and run it down to the empty light once every month or two.



-Nate

[QUOTE][

The amount of fuel in the tank has nothing to do with whether or not it will give you more pressure. The inlet/filter/pickup screen for the pump is at the bottom of the tank so it does not matter how much is at top but rather if the screen can pick any up off of the bottom.

 

Like I said, whatever priming the fuel pump actually does; it works. I actually dont wait 15 seconds, I normally just wait until all the lights and beeps turn off, then I start it. Try it on your car, or any car, and it will start faster.

Every car I've ever driven has started quicker/easier after I prime the fuel pump and if it's not low on gas. I've tried my method on the following cars: 96 maxima/accord/corrola, 99 accord, 97 318i, 95 neon. Those are all cars I've driven on a consistent basis and have experimented with, to know that priming the fuel pump and having a good tank of gas in the car allows it to start easier.

The technical reason for doing so I am ignorant to, but no way can someone tell me that a car that has a gallon left and has been sitting for a week will start with easier than a car in which has a full tank of gas and the fuel pump has been primed. A perfect example of what I am talking about is this; go to a used car dealership and try to start a car right off the bat (they don't like to keep much gas in em), it will take a little longer to turn over vs. if you had a full tank of gas in it and primed the fuel pump.

-Nate

 

[QUOTE]Originally posted by Daniel B. Martin
[I]Our 4Gen engine does not have hydraulic valve lifters.

Dan,
Is there a valve clearance adjustment for the 4th gen, or is it hydraulic?

Also, how is pressure maintanied in the fuel system after the pump is de-energized? I would think it would drain back, either by passing in the pump vanes or the return line.

 

In the VQ30DE engine there are no valve lifters, hydraulic or solid. Each cam lobe bears directly against a disk-shaped steel shim of precisely machined dimensions. Changing valve clearance is done by removing the shim and substituting another with a different thickness. This service operation requires special tools. The shims are made in a variety of thicknesses. They can be purchased from the dealer. I'm not aware of any other source for these shims.

Nissan does not include valve clearance adjustment with any scheduled maintenance. It should be done if and when the valves become noisy. On most cars this service will never be needed.

 

If everything is working right ...
(1) The fuel rail pressure can't drain "backward" through the fuel pump because the fuel pump assembly contains a check valve (a one-way valve).
(2) The fuel rail pressure can't drain "forward" through the return line because the fuel pressure regulator is the "gatekeeper" at the entry point of the return line. The FPR bleeds off pressure in excess of 34 psi. Anything less stays in the fuel rail.