car starts running strange around 2,500-4,000 rpm

robsta · Post by **robsta** » Mon Dec 24, 2007 1:56 pm

I was trying to get my cd player working this morning and after i put everything back together my car hasnt been running the same.
I have a Mivec controller and Apexi RSM in my car and they are reading about 1,500rpm higher then the standard taco. when i drive it over about 2800rpm according to the taco and about 3500-4000rpm according to the mivec controller and RSM the car starts running rough, the RSM goes blank and the mivec controller starts flashing. i have to stop and restart the car for it to run normal again, but as soon as it reaches that RPM again it will start running rough. any ideas as to whats wrong? im going to take it somewhere to get looked at after christmas.

jonowong · Post by **jonowong** » Mon Dec 24, 2007 2:35 pm

maybe a bad ground wire

Boris · Post by **Boris** » Fri Jan 04, 2008 2:38 pm

I hope you have figured it out by now as your post is fairly old.

But the problem is with the Mivec controller. When you unplug the battery it resets the memory on the Mivec controller, making it think that the car is a 4 cylinder car instead of 6 resulting in your Mivec coming on like at 2/3k rev range making it drive like a bitch.

Instructions how to set it up again are here:
http://www.mitsubishi-fto.org/parts/ele ... mvc85x.htm

You will also need to change the setting on your RSM to a 6 cylinder too to get the correct speed and RPM display.

robsta · Post by **robsta** » Fri Jan 04, 2008 3:14 pm

Thanks Boris! I'll try that when I get home tomorrow, I haven't done anything with it yet I've just been driving my girlfriends car around instead