RPM drops when clutch is step on?

[sketchman]

The use of a computers on a car engine has increased the efficiency of an internal combustion engine from 32% to 33% (until something goes wrong with the electronics).

I'd wager it was more about repeatability in manufacturing, efficiency in manufacturing, and keeping tinkerers out of the manufacturing after the sale than efficiency of the engine. That and government stupidity pushing for their favorite flavor of pollutant instead of what it naturally makes when you just tune it how it works best.

[sam]

Unplug your transmission and clutch switches one at a time to see if
a switch might be faulty. Test one at a time.

ok, will try this one. Thanks!

[sam]

You can also run with the iac unplugged

Greg, won't this affect my idle?

[Movin]

It could, what it does when you do that is helpful information!

The efficiency of the engines improve the closer you put liquid
fuel to the sparks plug. CIS vw engines were a huge efficiency
improvement over carbies, and they have no computer but the
same gains. Port injection is giving way to direct injection for
a substantial gain, both are computer. However, computers make
all aspects of performance, efficiency and repair much more accurate
and speedy to adjust, improve and diagnose. In most cases parts
are much smaller and lighter. But the real efficiency gains were
made by keeping liquid fuel off of the least possible surfaces between
point of entry and the spark plug. One concession, computer programming
allows direct injection to use low octane fuel and higher compression
levels with more timing without blowing holes in pistons. A huge efficiency
gain!

[FestYboy]

how old is your throwout bearing? and does it do it while in nutral with the pedal in or does it have to be in gear with the pedal in to do it?
an auto ECU will NOT lower the RPMs while in gear, the drag from the TC does that.