Very HIGH RPM= HIGH MPG

Jul 2, 2009 | 06:23 PM

roach_juts

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From: entertainment capital of the world, Socal

2000 e430( w210),1979 240D (w123), 1992 300e(w124), 1990 mitsubishi galant VR4

Very HIGH RPM= HIGH MPG

hello

i am wondering that my 1990 wagon has a high RPM, when the car is at idle the RPM is around 500 to 600 rpm which looks normal , but when i am driving it around 60mph the RPM is at 3K RPM , when i speed up to 80 MPH the RPm will me 4k RPM .. this seems not to be normal , because my other w124 if i run it at 80MHp the rpm is 3K RPM....

i did a change oil already, with ( oil additives)
added fuel injector clean & even sprayed the carb & injector
but nothing changed

i am thinking changing the distributor, rotor, fuel filter & O2 sensor
i hope this will help the RPM go down to normal

ANY SUGGESTION & ADVICE ??

thanks

Last edited by roach_juts; Jul 2, 2009 at 10:34 PM. Reason: mis type

Jul 2, 2009 | 06:45 PM

Saijin_Naib

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1990 300ce 24v I6

My CE tachs at about 4k at 80mph. The wagon and coupe have different gearing than the sedan.

Jul 2, 2009 | 07:12 PM

roach_juts

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From: entertainment capital of the world, Socal

2000 e430( w210),1979 240D (w123), 1992 300e(w124), 1990 mitsubishi galant VR4

Thanks for the info

Jul 2, 2009 | 08:55 PM

Real1shepherd

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1992 300TE 4matic wagon

Quote:

Originally Posted by roach_juts

hello

i am wondering that my 1990 wagon has a high RPM, when the car is at idle the RPM is around 5k to 6k which looks normal , but when i am driving it around 60mph the RPM is at 3K RPM , when i speed up to 80 MPH the RPm will me 4k RPM .. this seems not to be normal , because my other w124 if i run it at 80MHp the rpm is 3K RPM....

i did a change oil already, with ( oil additives)
added fuel injector clean & even sprayed the carb & injector
but nothing changed

i am thinking changing the distributor, rotor, fuel filter & O2 sensor
i hope this will help the RPM go down to normal

ANY SUGGESTION & ADVICE ??

thanks

First of all when you use the letter "k", that means time 1000, so that 5k is 5000RPM. I doubt if your wagon is idling @5000RPM. I'm sure you mean 500-600RPM. Mine idles brilliantly around 700RPM. As far as the RPM on the hwy....I can and have done 140MPH at about 6500-7000RPM. I can't tell you what RPM exactly, because I only glance at the gauges at that speed to make sure I don't go nuclear..

At 80MPH then, you should be somewhere in the neighborhood of 3500-4000RPM in 'D' which is overdrive. Your RPM is established by the gearing of the car. You can't change that with carb cleaner. There could be reasons your car is missing @idle or on the hwy, but that won't change RPM values for your motor and final drive ratios.

Kevin

Jul 2, 2009 | 10:36 PM

roach_juts

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From: entertainment capital of the world, Socal

2000 e430( w210),1979 240D (w123), 1992 300e(w124), 1990 mitsubishi galant VR4

thanks kevin for the typo error
the car shift like butter smooth ...

thanks for the info

Jul 3, 2009 | 10:46 PM

neanderthal

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I'm not even sure what the question is.

Jul 4, 2009 | 12:35 AM

Real1shepherd

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1992 300TE 4matic wagon

Quote:

Originally Posted by neanderthal

I'm not even sure what the question is.

Boiled down; What is the normal RPM of a 1990 wagon @80MPH. I was telling him what my '92 4Matic RPM runs at about 80MPH in overdrive and at 140MPH. He was also stating that his 300e runs less RPM than his wagon @80MPH.

The carb cleaner and his tranny shifting smooth was a curve ball, I believe.