Mechanics

NO PEDAL RESPONSE, OR SLOW ACCELERATION.

2008 Nissan Altima • 2.5L 4 cylinder FWD Automatic • 111,000 miles

I am in dire need of assistance with diagnosing a strange symptom my 2008 Nissan Altima Coupe 4cyl 2.5s is doing.

It all started on a drive to Utah from Arizona. We were going up an incline and got cut off by another car and had to push on the brakes. Upon trying to resume accelerating, we got not response from the gas pedal. Nothing at all, besides a slight acceleration until we pulled off the road. I could push the pedal to the floor with little to no response, and mostly no response. I turn the car off for a few minutes, started it up, and we were somewhat back to normal. It accelerated, but didn't have power behind it. It took much more to get to 80mph, or even 60mph.

But then, it would drive fine. For two days, it ran fine without incident. But on the drive home after a couple hours, I had it in cruise control, and heading up a hill it just kicked me out of cruise, and when I hit the pedal I got no response. Though it didn't slow down as if I removed my foot from the pedal, it slowly dropped mph until we pulled off again. If we turned the car off for a few minutes it would return to working (Though seemed to have lag in throttle.). It did it a few times more. Today during local driving it just seems to have a lack of response and throttle, taking more effort to accelerate.

It may have started a few days before the trip my girlfriend said (it's her car), as she said it did the symptom of not accelerating as fast as normal.

Any and all help is appreciated! Thanks in advance!
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Mystaray
June 9, 2014.




You need to scan for codes and check fuel pressure with a gauge first auto parts rent it

Hmac300
Jun 9, 2014.
Even though there are no lights on?

Tiny
Mystaray
Jun 9, 2014.
No light will normally go on with low fuel pressure

Hmac300
Jun 9, 2014.
Reading about the symptoms of low fuel pressure, it doesn't sound like it. The car never sputters, jerks, or has any other symptom besides no response when the gas pedal is pressed. The engine runs sound, and idles perfectly. We drove at least 300 miles before it happened on the way back, the first time.

My initial thoughts are the throttle body, or some sensor or electoral compenent. But, I am not even remotely comfortable with diagnosing mechanics.

Tiny
Mystaray
Jun 9, 2014.
Actually one other thing to add, when it does this, and right before it revs to over 3k rpms, and sometimes past 4k before it stops responding at all. That's the case also when it has a hard time accelerating.
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Tiny
Mystaray
Jun 9, 2014.
Until you scan for codes and check fuel pressure which are the basics you don't even have a clue where you are. Your computer could have stored a code and you don't know it. Also you need to check intake vacuum if 15" or below suspect a clogged converter/exhaust system. Or a clogged air intake for that matter.

Hmac300
Jun 9, 2014.
I have a very similar condition- with a 2008 Nissan Altima 2.5s Sedan- the first occurrence was around 75K on an incline at about 7,000 ft elevation near Colorado Springs. The second was more crucial, at a higher elevation (9500+), maybe 4K more on the odometer. In the first instance I found a parts store and being away from home, I decided to replace the air filter to see if that would work. It seemed to work, I had no further problems with the car until the more recent episode. In the case of the second problem I was ferrying my wife to pick up a car we had purchased; the dealer is a personal friend, and I asked him about the problem. He is an ex-GM factory rep and a multi-brand dealer (not Nissan). He was sure that it was NOT the air filter, that it is the fuel filter / fuel pump. I still don't know. The car ran fine over the high elevation and incline on the return trip, but I took it easy. I would like to know if there is any resolution to the problem since the circumstances are so similar. I have looked to see if this is a known problem with this car, Nissan seems to have a blind spot when it comes to high altitude- I say this because of experience with the tire pressure warning light. It comes on every winter, for as long as the cold weather continues, they have no fix or adjustment to address that problem.
Again, I wonder if your problem has been diagnosed, since there is no follow-up to the fuel pressure advice.

Tiny
Bake97
Sep 16, 2014.

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