lost performance

[ramsin32]

hi everyone
i have nissan 99 sentra which i bought new and it had a very good acceleration the first two years. i think i lost the acceleration whan i chane the spark plug a year ago ( speculation).

i have changed the oil ontime always. used systhetic most of the time. it has 48000 miles. i just changed the plugs to Bush 2 and changed air filter.

i am thinking about have a fuel injection cleaning? but i am not sure if it is help at all.

i also was thinking about changing fuel filter!!! what do u think.

assumming there is nothing wrong with engine; what else can i do to improve performance?


thanks

ramsin

[narcted]

What makes you think you lost acceleration? Is your 0-60 time longer? Did your car lose horsepower on the dyno? It's difficult to asses online a claimed loss of acceleration without quantifiable data.

I've heard claims of fuel injector cleaning improving performance. I'd just go to the local auto shop and try a $1.75 bottle of pour in tank cleaner rather than rush off and spend $50+ to have a shop do it. See what happens.

I'd also suggest looking at your air intake. It might be dirty. Air is not feeding into your engine as easily as it used to. Changing the air filter so your can breath easier may bring back the engine power. Air filter: Probably $10.

Did you add stuff to the car? Weight does make a car slower. If you want fast acceleration smaller wheels get up to speed faster. Also large diameter wheels are heavy and take longer to get to speed. Are you still using stock rims? Also consider air drag of antennas and spoilers, for example. You want your car faster, I can also suggest stripping weight from the car. Example loosing the spare tire can same you 10-20 pounds. At extremes, your interior may weigh over 100 lbs. And who needs to use an air conditioner? It steals horsepower. Turn it off or take the compressor off the engine. Cost of taking off add-on or dumping weight from car: $0 Check out the July issue of Sport Compact Car to see what I mean. The technical staff actually bring a Nissan Sentra's track time down from 15.6s on the 1/4 mile, to 13.4s. And without spending any money. True they chopped the car to bare bones, but they improved its acceleration.