Manual choke idle

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jimi
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Re: Manual choke idle

Post by jimi »

Surging idle rpm with the engine warm and the manual choke on is normal, if you read this article,
https://www.mr2oc.co.uk/know-your2/mk1/ ... rsion.html
Paul explains why it happens (in effect its the same as the waxstat being stuck open)

The second issue could be related to several things. The idle going up to 1000 when the lights are on is normal, your activating the "idle up" circuit which opens the idle up vsv and adds extra air past the throttle body and increases the rpm by approx 200, this is designed to compensate for the increased load on the alternator causing the idle to drop and is normal. Idle up is activated by turning on the following
Lights
Heater blower
Heated rear screen,
Brake lights
Radiator Fans
A/C ( if fitted)
Easy check is with everything electrical off, put your foot on the brakes, idle rpm should increase by 200.
A couple of things to check/try,
Check that the throttle stop screw and/or the throttle cable are not holding the throttle butterfly open. If they are OK with the engine warm & manual choke off, try adjusting the warm idle screw (under the round black plug on top of the throttle body) turn it anti-clockwise and the idle will drop and possibly even stall the engine, adjust it back clockwise to get approx an idle speed of 850 rpm. If the engine runs ok at that then your done. If it's still rough try adjusting the mixture control, see the last page of this article for details https://www.mr2oc.co.uk/download-cats/d ... 2-ecu.html


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jimi
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Re: Manual choke idle

Post by jimi »

Edited my last post to add the radiator fans to the idle up list, forgot about them :blush:
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sharingan
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Re: Manual choke idle

Post by sharingan »

arctichotspur wrote: ↑17/03/21 19:43 Update/Solution:

Got the VSV recommended by Jimi and Paul Woods in the mail today and connected it to the car. With this VSV the engine idled at 1600 rpm gradually rising to 2000 rpm. It finally works and I don't have to worry about cold starts anymore.

If you are doing the manual choke conversion; Don´t try other(cheaper) VSV´s. Just use the one that actually works and does the job!
May I ask which VSV you get recommended? Thanks :)
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jimi
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Re: Manual choke idle

Post by jimi »

Know Your 2 is your friend ;)
https://www.mr2oc.co.uk/know-your2/mk1/ ... tions.html
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