Hard shiftin' 2000 Altima and TPS Senson malfunction... help!?!?

I have a 2000 Nissan Altima with almost 100,000 miles on it. It was in a front end collison (not major) about 2 months ago, and I just started having problems. Last week, the Check engine light came on, code diagnosed as "Throttle Position Sensor malfunction." Today, the transmission started shifting hard. It's time for an oil change, so I was going to do that today, also get a new air filter. Fuel injector cleaner with next gas tank. The belts just started making a heck of a lot of noise, but my car has never liked winter, and they were replaced last year. I'm going to have those looked at just in case tho. Can any of the other stuff going on cause that shifting problem? Any other suggestions for routine maintenance? I'm going to take it in, but I was hoping to get a little more info, as I'm not familiar with many mechanics in the area.


Ok, so I took it into the shop today, and the repair shop diagnosed it as the temperature gauge, not the TPS. So they repaired it, but it's still shifting heavy... but they said nothing is wrong with my transmission. Any other ideas?

2 Answers

  • Anonymous
    1 decade ago
    Favorite Answer

    The throttle position sensor is the cause of all your problems. There probably isn't anything wrong with the transmission, since the computer uses information it gets from the TPS, and the speed sensor, to determine when and how hard the transmission shifts. Most of the time most anyone could change the throttle position sensor (TPS), but some of them must be calibrated on the signal voltage, and requires a meter to adjust this. If this is not set, the transmission still may have some weird shift points and other issues, so have it done right, and you will be glad you did. The collision you had probably doesn't have anything to do with what's going on with the car now, so I wouldn't worry about that.

    You might try to ask some friends, or neighbors about a good mechanic they could reccomend or use. The best idea is, to find a good mechanic, and stick with him. When you go there, tell him you are looking to find a regular mechanic that can take care of all your needs, and they will do a good job so they will get your future business. Whatever you do, DON'T say anything about mechanics being rip off's, as you will get on their bad side right away, and you don't need that. Some ARE rip off's, but take a look inside their shop, and if it is clean, neet, and organized, then the odds are they take pride in their work, and do good work. Don't go looking for the cheapest mechanic either, as with any business you get what you pay for. The people that are good at what they do, generally get a pretty good payday, as this applies to any business for that matter. If the belts are making a noise, then they need looked at. I hope I have pointed you in the right direction. Good Luck!!!

    Source(s): Certified Master Mechanic 40 years experience
    • Commenter avatarLogin to reply the answers
  • Mary
    Lv 4
    4 years ago

    It depends on the car's mileage and the maintenance/repair record. If it's over 70,000 miles, then $7000 might seem a bit excessive. If it's been in an accident that involved fixing the motor, then definitely don't buy it unless it has a warranty. Are you certain you want a old-generation altima though? Personally, i would spend a few extra thousand for a brand new toyota or honda, knowing it would last till a lifetime.

    • Commenter avatarLogin to reply the answers
Still have questions? Get your answers by asking now.