Car will not accelerate?

Hi jwhitehead1303,

Is the Check Engine Light indicating?
Have you tried to retrieve for trouble codes?
Was any repairs carried out prior to this occurring?
Was the MAF replaced new or used?

This guide can help us fix it

https://www.2carpros.com/articles/engine-has-low-power-output

Please run down this guide and report back.

The code indicated Mass Air Flow sensor issue. I replaced with a new sensor, but still show check engine code.

What is the trouble code?
Did you test the winings ?

I am still getting the mass air flow sensor problem code. Is it possible to reset the ECU / ECM my self?

A scanner is the best way to reset the code.

Go to Autozone for a free scan and they can reset the codes for you.

I need to know the exact trouble code.

Hello,

I've been going to my local shop for aprox 2 months now (not a nissan dealership as they charge too much for diagnosis). They have a few ideas as to what they think is wrong with the car, but dont want to fix anything yet just to make sure. My Mech does not want to buy parts that may not even fix the issue.
So..... code read outs are:
engine mis-fire
too lean (bank 1)
Code 24 (we have no idea what this is as the computer saye "see svc manual")
and the TPS sensor

Car symptoms are:
I cant accelerate AT ALL...i have to tap the gas lightly to get to 40km/h..not even the speed limit on the side roads...the hwy-FORGET IT. the engine bogs when giving it gas......if i floor the pedal---nothing goes to the engine...and the engine doesnot even rev---no RPM change. Also, the engine will sometimes shuddler and violently shake when at 2000rpm while driving slow. One day I thought it was going to explode or drop from my car...thats how violent the shaking was.

What could this be? How can we test the parts without replaceing them...cause I dont want to purchase parts I dont need!!!

Urgently needing help!!!!

engine mis-fire
too lean (bank 1)
Code 24 (we have no idea what this is as the computer saye "see svc manual")
and the TPS sensor

Do not replace any parts just yet.
Have your mechanic check your timing. Your timing (in my opinion) is too advance. That is what P024 stands for. It will also cause the engine misfire.

Clean your MAF sensor and intake air temp sensor. Also make sure that you don't have any leak in the vacuum system. Any of these will set off the system too lean condition.

Also have them do fuel pressure test on the fuel rail making sure that you get the right fuel pressure.

Let us know.

They already played around with the timing and cleaned out the sensors. They found a leak in the vacuum and fixed it. They also did a fuel pressure check...many parts were taken out...cleaned, and replaced. Nothing changed.
Is there anything else that may need to be checked?
Is it possible that the PCM is fried? How can we tell?
Is there any specific test for the Sentra SE to tell if the computer is fried? Can this be causing all my symptoms?

Sometimes, the car runs better....with more acceleration being able to drive it on the Hwy...then a few days will pass and it will get soo bad that its not safe to drive period. It varies btn these 2 states.

They are all boggled--I even took it to another mechanic for another opinion....he is also boggled as he chkd the same parts.

I may have a transmission issue, but I'm hoping that the tranny is just acting up due to the poor driving condition of the car. The tranny symptoms keep changing on me...from a slipping gear, to throwing itself into gear hard. For now, its pretty smooth except due to poor acceleration it cant get into gear--it's working like it's confused!!!

Thank you for your help,
Irene

If your PCM is fried, the car would not even run at all. After discussing with other Sentra enthusiasts, we came to the agreement that you need to check your camshaft position sensor. '00 - '01 SR20DE engines are plagued with bad cam sensor. So have that tested.

I don't think you have issues with the transmission. It is probably acting up due the engine mis-performing.

Thanks for the info.

My car is practically not running...that's why I was going to get the PCM tested tomorrow by Nissan, but I hate taking my car to the dealerships.

I will run that info by my mechanic.
Wouldn't this have shown up on the code read out? How would the cam sensor be tested without having to buy a new one inorder to find out?
Can be that easy that only 1 sensor needs to be taken care of to stop all these issues?

(FYI-both O2 sensores are new-aftermarket- )

I'm extreamly frustrated & exhausted with this issue. I wish I knew more about cars..then maybe I wouldnt be so flusterd.

I am really thankfull for all your suggestions.
Thanks,
Irene

[quote:ca8fbbd435="bastardgirl"]
Wouldn't this have shown up on the code read out? How would the cam sensor be tested without having to buy a new one inorder to find out?
[/quote:ca8fbbd435]

A lot of times, the cam sensor gives out reading. And for as long the reading is within range, PCM sees it as "operating within normal parameter". The problem that most Nissan vehicles experience is that the voltage and resistance of the sensor so fluctuates erratically that the result of the PCM trying to compensate is shown as "gas, no gas, more air, oops, less air, gas, more air, less gas, ......." You get the picture. That translates to the car bogging down, won't go faster than certain speed... And as far as the PCM goes, it sees the cam sensor works within its range.

You don't have to buy a new one just yet. You don't even have to pull it out of the bell housing. Just check the voltage of the connector. I am not at home, so I don't have access to the specs. The older SR20DE spec is 5.0 volts on the connector, and the resistance is within 166 to 204 ohms.

If the specs are out of range, you will get codes for cam sensor, usually P0010 through P0025. Wait a minute. You do have P0024. That stands for "B" Camshaft Position - Timing Over-Advanced or System Performance (Bank 2). I just noticed that. There, you have just diagnosed the problem.

AWESOME!!!

I will keep my fingers crossed...going to test the reading on that sensor tomorrow. I really hope that this is it....I cant take the car running this way any longer.

I will keep you posted on the outcome of this.


Irene :)

I am having a problem diagnosing a my Sentra's problem. When I bought the car I was told that the fuel pump was bad. I checked the pressure and it was only 22 lbs. I was told that it was supposed to be 44 lbs. so I replaced the pump but am still having the same problem.
The engine will run at idle but not rev up without hesitating.
It sounds like it is starving for fuel. I opened up the air box and tried to rev it up but it was doing the same thing, but when I partially block the air from going in it runs smoother and will rev up a little easier. I unplugged the MAS and it ran the same.
Thanks in advance

Well.....acording to my Mechanic....everything was already chkd.

I give up on the car...I'm getting another one.
He is flustered with my car....and so am I.

Thanks for ALL the info!!!!!
Much appreciated!!!!

[quote:990f409469="mikifin"]I am having a problem diagnosing a my Sentra's problem. When I bought the car I was told that the fuel pump was bad. I checked the pressure and it was only 22 lbs. I was told that it was supposed to be 44 lbs. so I replaced the pump but am still having the same problem.
The engine will run at idle but not rev up without hesitating.
It sounds like it is starving for fuel. I opened up the air box and tried to rev it up but it was doing the same thing, but when I partially block the air from going in it runs smoother and will rev up a little easier. I unplugged the MAS and it ran the same.
Thanks in advance[/quote:990f409469]

The TPS and MAF data should correspond.bench test both.

I am sorry it didn't work out. I hope you find a better car than what you have now.

when i accelerate sometimes it doesn't seem to respond, when i'm hitting about 75-80mph it won't shift all time, and when i stop at a light or something about 15 seconds after i stop the whole car starts to shake and then it stops and does it again about 15-20 seconds later, but the shaking goes away when i start back up. It wasn't doing this until i took it in a few days ago for a tune up. they said they think it might be a leak in the air manifold gasket??? or something like that. please help with any suggestions.

If it wasn't doing this prior to the tune up, I would have them recheck their work. It sounds like they may have missed something. The shaking sounds like the engine is missing. Has the check engine light come on?

i was driving my car it started to sputter and lose power barely made it home going about 15mph then it died wont turnover i added some antifreeze what could it be

The information provided is not sufficient for us to understand what could be wrong. You need to perform some testings to find out what is wrong. Click the link below for more information.

https://www.2carpros.com/articles/car-cranks-but-wont-start

sometimes, when I'm driving and almost going uphill my car hestitates/loses power, I can see the rpm jump down and then after 3x of this it goes back to being norma.? what could be causing this?

Check and test the following below:

Oxygen sensor
Dirty fuel injectors (cleaning the injectors often fixes this).
Bad MAP (manifold absolute pressure) sensor
Bad TPS (throttle position) sensor
Bad or dirty MAF (mass airflow) sensor
Low fuel pressure (leaky fuel pressure regulator or weak fuel pump)
Vacuum leaks (intake manifold, vacuum hoses, throttle body, EGR valve)
Bad gasoline (fuel contaminated with water or too much alcohol)

Sometimes, what feels like a hesitation is actually ignition misfire rather than lean misfire. The causes of ignition misfire may include:

Dirty or worn spark plugs
Bad plug wires
Weak ignition coil
Wet plug wires

Nissan Sentra 140GXI was replaced with new fuel pump but now when you hit the road, the rev count does not pull more than 2000 rpm. When it reaches 2000 rpm it grips as if the pump does not push enough pressure

-Original fuel pump ceased to pump and was replaced with New fuel pump
-Cleaned injectors with Wynns injector cleaner
-Car was fully serviced
-All along it was good but, sometimes after engine wash it starts to cut idling, the rev count goes up and down.

You should take it back to the shop and have the fuel pressure checked. Also, check the fuel pressure regulator and make sure the electrical connector, your car may have a vacuum line, is connected.
Still have pressure checked and it would not hurt to have the trouble codes pulled either.

The fuel pressure regulator is in good condition since when I pulled out the pipe connected on it,the engen idles abnormally and there is no fuel coming out. Its only air flow.Now I agree the problem is with the pump since it is not the original pump (not nissan but FEMO manufactures of the car.Unless I get recommended pressure pump measurements. i.e. 6-7kpa

I have had high quality aftermarket pumps fail on me, so it is possible as the first start is kind of tough on the pump. Checking the pressure is the best way to check it and you would have no other reasonable option but to replace it. Also check for anything that could impede the flow of fuel in the line. If you have an inline filter, you do not I believe as the filter is a sock type that is attached to the pump. Make sure hoses are routed properly.

I just had a tuneup and oil change by my mechanic. He also tested compresion and said all's fine. 140 across. Valves good no need for adjustment. He also cleaned fuel injection system. Then I drive home and smoke starts coming out of tailpipe. I figured it was carbon. I return car next day after smoke continues and runs sluggish losing power. He says it could be a bad vacuum modulator. But, I'm worried about credibility as I've never had any smoke and he gave car clean bill of health within the 24 hours of the smoke beginning. What is up with this? The car is in his shop for the weekend but I'm concerned and anxious. What could this possibly be?

What was the color of the smoke? You sounded like its gonna cost you an arm and a leg. What vacuum modulator is he talking about I hope its not the tranny.

Inbox :: Message
From: seanfields
To: rasmataz
Posted: Sat Feb 16, 2008 4:50 pm
Subject: Vacuum modulator and color of smoke
It was grey and maybe blue. My mechanic said it was oil burning. He said the Vacuum modulator when it goes bad burns oil. It's a trans part. My question when he cleaned the fuel injection system could he have done something wrong and created the problem? When I first drove the car it seemed to lose a little something when I got it home after driving 50 to 60 miles then back down to a stop and going again it seemed to want to stall right around 20 but would pick up. The next morning is when the smoke happened. It's not a steady stream of smoke just happened 4 or 5 times before I got it back to him. I probably drove the car 20 miles at least before returning to his shop. Could there be damage to a piston or a valve due to a fuel mixture problem with the fuel injection system after he cleaned it.

I don't think the injection cleaning will caused the smoke

If the vacuum modulator is leaking transmission fluid will be drawned into the intake and get burn in the combustion chamber and as a result it will produce a whitish looking color.

Bluish color is an indication of oil being burned-get the engine compresssion checked to identify a problem with valves and rings

Engine is losing power and shuttering out when i hit speeds of 40mile per hour plus,Nu tis fine at speeds under 4o miles per hour.

Has the check engine light come on? HAve you checked fuel pump pressure? Have you checked to make sure the catylatic converter isn't plugged?

Let me know.
Joe