idle problem mfi car

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PeterK
DDK rules my life!
Posts: 1270
Joined: Mon Sep 01, 2014 3:04 pm
Location: GU51 - Fleet, Hampshire, UK

Re: idle problem mfi car

Post by PeterK »

My hanging tickover issues were a combination of carpet on the pedal & the accelerator rod getting caught up within the tunnel
'79 Targa - restoration now mainly complete & being driven
http://www.ddk-online.com/phpBB2/viewto ... 28&t=59756

and now CIS to EFI
viewtopic.php?t=72921
rft218
DDK forever
Posts: 509
Joined: Wed May 16, 2012 9:24 am
Location: Cornwall

Re: idle problem mfi car

Post by rft218 »

Hi,

This is my third attempt at replying, so apologies if you get a few posts!

I think have had the same issue with mine that I have just fixed. The issue I tracked down to speed switch/mircoswitch/mfi solenoid.

I have a classic retrofit cdi box that feeds a relay and replaces the speed switch. That goes through a relay and then when teh rpm drops it allows 12v to teh microswitch so that if you have your foot off the throttle it activates the solenoid on the MFI to cut the fuel.

I had an issue with the relay and wasnt seeing 12v at the microswitch so the MFI solenoid wasnt operating when throttle was off. That meant it was doing 1500 rpm at junctions but would eventually go down to 800 rpm at a random time!.

Hope that helps,

Cheers

Roger
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