rpms
 

2002 mustang 3.8 v6 4000 rpms is all i can do is there a way to get more out of it :confused: :D

i take its an auto. it should only go to 4k while in park or neutral, im not recommending it but if you hammer it in drive you'll see it shift at a higher rpm depending what gear your going into. and if you dont like where your shifting at you can by a tuner and adjust your shift points

yeah, are you talking about reving it in N or Park ? if so then that is normal and there is no reason you need it to rev any higher. As for when it is in Drive, i think it went to right around 5k~. If it won't go that high in Drive then start checking all the basics.

buy a sexy true blue cobra like mustangv6

Not a auto 5 speed it does this throgh the geares

You mean to say that it actually cuts off power at 4k, as if you were hitting a rev limiter? Or, does the acceleration slowly drop off as if you have no top end power?

sounds like the car is dieing out above 4k. Start by checking spark plugs, wires, fuel filter, MAF sensor. If all those check out, then it sounds like it is probably a fuel injector giving out(not being able to keep up with the rest, hence the lack in power and inability for the motor to rev).

A tune up seemed to do the trick thanks for all the help.

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5 speed trans spedo workes part time new speed cencer samething there is a black box about 1.5 x3 inches wired in it says ford raceing on it no clue help. :confused: :confused: