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Hi All, I am a newby just joined. I have a 2003 Rav4 which has done 95000K and owned it for 3 years. It has performed flawlessly except I have never liked the high revs when cold which doesnt go away until it warms up. After about a year of ownership decided to ask the local mechanic if the idle revs where adjustable, of course no they are not and he told me some of his customers say their cars run up to 2000 rpm cold !!!! .
So I decided to put my electronics thinking cap on and to cut a long story short after 3 months of R and D invented a RPM control module.
This is a small box less than the size of a playing card and fits in the engine bay.
What it does : short answer , changes the signal the sender sends to the computer effectively telling the computer the engine is already hot and the computer in turn adjusts the Idle Control Valve accordingly which drops the RPM.
The Idle revs are completely adjustable with a control knob anywhere from maximum idle to what ever you want to set it at . I have adjusted mine to be 800 RPM.
There is a short delay of a few seconds before the unit switches on to allow the engine to cold start normally.
The unit has been test running in my vehicle for 6 months with out a hitch. Have decided to manufacture and sell these so if anybody out there would like to get rid of those annoying high idle revs you can contact me at [email protected] re price and delivery anywhere in Australia

Cheers Geoff
 

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@Mr Tinkerer Its normal for these four-bangers to cold idle at 1500-2000+ rpms. There’s already a computer module that adjusts when warm. Not sure why you would want a lower idle when all the engine wants to do is warm up to optimal temp and lower it’s rpm range. Adjusting anything manually is asking for premature wear and fuel consumption.
I applaud your modding ability, really, but just let the engine & ECU do the adjusting.
 

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@Mr Tinkerer Its normal for these four-bangers to cold idle at 1500-2000+ rpms. There’s already a computer module that adjusts when warm. Not sure why you would want a lower idle when all the engine wants to do is warm up to optimal temp and lower it’s rpm range. Adjusting anything manually is asking for premature wear and fuel consumption.
I applaud your modding ability, really, but just let the engine & ECU do the adjusting.
Hi CWHITE,
Thanks for the feedback. Personally I like idle revs to be in the 750-800 range and what ever the Toyota engineers were thinking , I am sure they probably thought they were doing the best thing by increasing the revs at idle. I think there is a fallacy over running cold engines increases wear, why?, its assumed oil doesn't get to all parts of the engine where we would like it to be ( particularly the cylinder bores) but remember the oil when cold only has a viscosity of 10 very thin indeed. Its viscosity only changes when it starts to get warm for a different reason. so we can say the engine is always well lubricated weather its cold or hot. Oil never used to be variable viscosity ie 10-40 , or 10-50 etc it used to a fixed viscosity and you had to choose which was best for your engine. You can see how the wear idea would come in when cold..
From another forum one guy with a manual gearbox was complaining because his gearbox clunked when putting it into gear, his car was garaged in a closed gararg and he didn't want to wait 3 mins filling the gararg up with carbon monoxide. Another driver wanted a way to reduce her revs as she lived just round the corner to a school crossing and when she was stopped by the lollypop lady who gave her a glaring look through the windscreen as the Revs on her car was telling her she was impatient to get going
 
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