# 98 Altima GXE Misfiring?



## Bruce MacKay (Nov 26, 2007)

Help!

I've a 98 Altima GXE that, without warning, will drop from four to three, and apparently sometimes two, cylinders. Flooring the accelerator actually slows the car even further; pumping the accelerator sometimes clears the problem.

My son maintains the car for me; he's an ASE Master Tech - and he's frustrated. OBD II shows no codes at all. We've replaced the plug wires (2x, no improvement), and the valve cover gasket. He's checked the sources available to him, but nothing makes sense.

Problem occurs under heavy load, and under light loads; rain and shine; day and night, hot and cold. The only common denominator is that I'm driving, and ASE Master Tech is not in the car. We picked it up today from a three-day exam that failed to identify the source of the problem - largely because the car behaved. Not 4 minutes out of the shop, it misfired - and continued to misfire as I limped it back almost all the way to the shop; I swear the car saw the shop's sign and began running normally. I collected tech for a prolonged check ride, during which the car behaved beautifully. 10 minutes after I let him out, misfiring resumed.

In the Old West, they'd shoot horses for less....

I drive in the Washington DC area - the nation's 2nd worst traffic. The idea of being at speed and losing power is disconcerting at best, and life-threatening at worst.

This is really the only problem this car has given me; it's pushing 140,000 miles and otherwise is as reliable as the sunrise.

HELP!

Thanks in advance.

Bruce MacKay
98 Altima GXE

(I'm a newbie; I've reviewed as many posts as I could find that even seemed related, but didn't find anything that seemed similar enough to avoid putting this post up. If I've missed a relevant post, my apologies)


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## jo31b (Oct 24, 2007)

Good Morning Mr. Makay,

Could you or your son list the things that have been looked at since the problem started?

Could you also list any repairs or maintenance that had been completed shortly before this began? (No matter how unrelated it seems)

Before we try anything else, we need to make sure that all of the basic needs of the car are met. So any scheduled maintenance that was overlooked up to this point needs to be done. Otherwise we will be chasing our tail and the frustration will cost a lot of money if you try to sell a car with an engine management problem plus the cost of a new car.f

Just to double check, you are saying that the car misfires throughout its operating temperature? (First thing in the morning, as it warms up, while it is at full operating temperature, full throttle, part throttle) 

Does it stumble at Idle?

Do you ever hear a pronounced ping just before it starts to stumble?

Are there ANY other problems with the car right now?

And if I am too late responding, could you list the solution to your problem?

Thanks very much


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## Bruce MacKay (Nov 26, 2007)

jo31b said:


> Good Morning Mr. Makay,
> 
> Could you or your son list the things that have been looked at since the problem started?
> 
> ...


Good Morning Mr. Makay,

Could you or your son list the things that have been looked at since the problem started?

>>OBD II finally reported either a malfunctioning transmission or a malfunctioning throttle position sensor. Replaced the sensor, and for a couple of days car ran extremely well - then the problem returned. OBD II reports transmission would go to fail-safe mode, capping RPM at 4,000 (which I never saw; I was capped at 3K) and leaning out the injectors as necessary to keep speed down. 

Could you also list any repairs or maintenance that had been completed shortly before this began? (No matter how unrelated it seems)

>> Only repairs/maintenance was periodic oil/filter change. 2 months ago, replaced all tires.

Before we try anything else, we need to make sure that all of the basic needs of the car are met. So any scheduled maintenance that was overlooked up to this point needs to be done. Otherwise we will be chasing our tail and the frustration will cost a lot of money if you try to sell a car with an engine management problem plus the cost of a new car.f

Just to double check, you are saying that the car misfires throughout its operating temperature? (First thing in the morning, as it warms up, while it is at full operating temperature, full throttle, part throttle)

>> Behavior happens throughout operating temperature range. Partial throttle provides best response; full throttle causes extreme lean condition and actually slows car down.

Does it stumble at Idle?

>> Haven't noticed. Seems to idle smoothly. 

Do you ever hear a pronounced ping just before it starts to stumble?

>> No pinging/detonation sounds heard at any time.

Are there ANY other problems with the car right now?

And if I am too late responding, could you list the solution to your problem?

Thank YOU! I'm considering shooting it...I was en route out of town on a week-long business trip when the car failed tonight. Tomorrow, I head out on a shortened trip - using the Miata, which is fun to drive but a pain to live with for a week on the road.

Bruce MacKay

Thanks very much


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