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Increasing Idle issue on Tercel

Posted: Mon Feb 09, 2009 10:05 am
by Jo_Tercel99
Hi everybody,

here the link to explain my project.

http://www.msruns.com/viewtopic.php?f=104&t=22749

I have a problem with my megasquirt. I now sharing sensor with the stock ECU. The megasquirt doesn't contrôle the engine yet. When I plug the Megasquirt my idle increase from 750 RPM to 1250 RPM. I first tougth that it was my 12V source that was the problem. It was plug on the ECU 12V source and I tought that it was because it was seeing the electrical load increased so it increased the idle. But, I plugged my 12V source directly from the batterie, control by a relay and it didn't change anything.

Could it be because I'am shearing sensor ?????

Thank you

Re: Increasing Idle issue on Tercel

Posted: Mon Feb 09, 2009 10:14 am
by Matt Cramer
Which sensors are you sharing?

Re: Increasing Idle issue on Tercel

Posted: Mon Feb 09, 2009 11:09 am
by Jo_Tercel99
I'am sharing the

CLT,
IAT,
TPS,
NE (+ Trigger signal from VR sensor),
NE- (- Trigger signal from VR sensor).

They all seems to work fine.

If you need more informations feel free to ask

Re: Increasing Idle issue on Tercel

Posted: Mon Feb 09, 2009 1:06 pm
by Matt Cramer
Have you removed R4 and R7?

Re: Increasing Idle issue on Tercel

Posted: Mon Feb 09, 2009 1:40 pm
by Jo_Tercel99
No, I don't, should I ? Do this resistances will affect the signal to the stock ECU. If I remove it, should I have to found the right resistance for my system or I just need to jumper them or let them empty ??

Thank you

Re: Increasing Idle issue on Tercel

Posted: Tue Feb 10, 2009 6:45 am
by Matt Cramer
To share temperature sensors, you must remove R4 and R7 or you'll confuse the stock ECU. Then you need to recalibrate the MS for your sensors and the stock ECU's bias resistors. Please see this link:

http://www.megamanual.com/v22manual/sharesen.htm

Re: Increasing Idle issue on Tercel

Posted: Tue Feb 10, 2009 4:37 pm
by Jo_Tercel99
Problem solved. Thank you Matt :D