4AFE High RPM at 100KPH

**devond** · September 19th, 2010 04:19 PM

sa tingin ko po yung rpm gauge ko may problem, paano po nirerepair ang rpm gauge? electronoic po yata yun di ba?

**Dr.Kamiya** · September 19th, 2010 04:56 PM

The only possible culprit here is your clutch, or a faulty gauge.

It's impossible for mods like spark plugs, air filter, ignition coils or basically anything inside your engine bay to affect your driving RPM, because your engine speed is tied to your transmission. Doesn't matter how strong or how weak your engine is, when you're driving there is a straight mechanical link between your engine, transmission and the road that basically locks your vehicle speed and engine RPM (per gear) together.

So if your driving RPM is being changeable, then something is slipping -- likely the clutch. Otherwise you'll get the same 3000rpm at 100kph (based on the original post) every single time.

If you really want to cruise at a lower RPM, what you need to change are the transmission gear ratios, or the final drive.

**Dr.Kamiya** · September 19th, 2010 05:03 PM

Originally Posted by zalds69

i got honda civic 95 with d15b vtec-e engine manual transmission...mine at 5th gear is 3250 RPM at 100kph and 120kph at 4000 RPM. kung hindi normal what cpuld be the problem?

Do some math.

100kph / 3250rpm means in 5th gear, your car needs 0.0307692308 rpm per kph
multiply that by 4000rpm and you get 123kph.

Your car is behaving perfectly normally.