During normal driving and in anything except full throttle application my 1996 maxima operates flawlessly other than the occasional starting problem expressed elsewhere on this site. However, during full throttle, white smoke comes from the tail pipe. My car is always warm by the time I do this so I can't attribute it to the normal emissions seen while warming up on all cars. The only thing that keeps me from thinking that this isn't a blown head gasket and coolant contamination is that the only way this can be evoked is with full throttle application ( nothing less will cause it). So, I'm wondering if at full throttle the ECU provides the engine with a different fuel mixture that would cause it to go white, which doesn't seem likely. Any experience would be appreciated.

Thanks in advance,
Jeff

 

The easy way to tell if it's a head gasket is to see if there is water in the oil, oil in the water, or a drop in the level of either.

You didn't say how many miles you have, or what kind of maintenance you've done. Here's a WAG (wild-***-guess), check your air fliter. If the filter is not flowing enough air because of dirt, it could produce a rich mixture at WOT.

 

You also mentioned that you had problems with starting once in a while. Even if you do not have a check engine light, check to see if it has a code stored in the computer. The light does not always light up when there is a problem at first. My car did the same stuff as yours did and it turned out to be the Engine Coolant Temperature Sensor.

 

smoked white a couple time at full throttle, and I'm guessing it is something MAYBE normal. I'm a STOCKER

 

Mileage :70,000 miles

After buying the car at 60,000 miles from a dealership and reviewing receipts confirming a full 60,000 mile service, I have followed up with 3,000 mile oil changes, one air filter, fuel filter, and PCV valve. The check engine light did come on once about six months ago. About that time their was a recall on the evap canister and some other things, I took it into the dealer and all of that was replaced under warranty. I just checked (visually and by smelling) and the oil had no visible water anf the oil smelled like well... oil. The fluid level is only a coolant level is only down a tiny bit since I changed it last summer. This is just by looking in the coolant reserve tank and I had just attributed this to a normal loss since it was so little. Thanks once again for the help and if any further experience can be input it would be greatly appreciated.

Thanks once again,
Jeff

 

Have you had the need to replenish the brake master cylinder reservoir?

 

I have never needed to top off the brake fluid reservoir, but I have yet to change it (next project on my list). I have been racking my brain in attempts to think of other problems that have shown up on the car. Sometimes it is hard to start, especially after letting it sit for approximately 3 hours I have to crank it longer than normal. Yesterday, after suggestions to check the ECM for codes I did so and got the 0304 code. This is the code referring to the knock sensor. I would assume this was because my sister put some regular gas in it while borrowing it since the MIL light never came on. I will have to pull out my trusty multimeter and check this out though. Thank once again to everyone for all the help, it is much appreciated.

Thannks,
Jeff

 

It is unlikely that running on regular gas caused Diagnostic Trouble Code 0304. I cannot understand why a DTC was set without the MIL coming on. Maybe it turned on and then off before you purchased the car.

Here is some information about the Knock Sensor, taken from the '99 Maxima factory service manual. I think it applies to your '96 model as well.

1) Raise the hood. View the engine from the driver's fender. Look into
the deep valley between the cylinder banks and below the intake manifold.
Identify the KS as a black item fastened to the block by a single vertical
bolt. A wire harness wrapped in black leads toward you, out of the valley.
That is the KS sub-harness.

2) Follow the KS sub-harness to it's nearest connector. This is connector F121.
It is located near the upper right-hand corner of the valve
cover of the forward cylinder bank, as viewed from the
front of the car.

3) Disconnect F121. You have to do a "press the latch and wiggle and
pull" to disconnect it. F121 has only two pins; if you see more than two
pins, you have the wrong connector. Use a digital ohmmeter capable of
measuring more than 10 Megohms. You want to measure the pins of F121, not
the sockets of the matching connector. Measure the resistance between a
good ground (such as the battery negative terminal) and pin #2 of connector
F121. On my car this is the highest of the two pins, the one closest to
the front of the car. The factory spec is 500 - 620 Kohms.

The manual says you have to remove the intake manifold to replace the KS. However, I think that a person with good dexterity and a 10mm ratcheting box wrench could replace the KS without disturbing the manifold.

 

Hey Daniel,
I,m assuming that you were thinking the fluid went from the master cylinder to the booster and into the intake system and finally through the exhaust?

 

Yes. Unusual, but possible.