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Mr30 Problem - Engine Cuts Briefly Then Runs Ok

jrh001
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jrh001 Proficient

jrh001

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Hi,

My '83 MR30 (2.4E) is running with a newly-fitted reco distributor.

After a cold start, I drive for a few minutes and, under acceleration, the engine cuts for a brief second and then runs normally. It only happens _once_ and the car runs fine after that.

Any ideas what the problem could be? I'm wondering if the vac advance mechanism may be sticking and then moving suddenly. Or is there some kind of cold start switch that could be at fault?

JohnH

  • 2 weeks later...
jrh001 Proficient

jrh001

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Posted
Hi,

My '83 MR30 (2.4E) is running with a newly-fitted reco distributor.

After a cold start, I drive for a few minutes and, under acceleration, the engine cuts for a brief second and then runs normally. It only happens _once_ and the car runs fine after that.

Any ideas what the problem could be? I'm wondering if the vac advance mechanism may be sticking and then moving suddenly. Or is there some kind of cold start switch that could be at fault?

JohnH

Could it be this component?

gallery_61769_3367_25138.jpg

(And what is that component?)

JohnH

jrh001 Proficient

jrh001

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How does it idle before and after?

Does it idle higher before it does it? then go normal after it does it?

Hi,

Idle after a cold start, 1100rpm.

Idle after a 10 minute warm up, 900rpm.

Idle after a 30 minute drive, 1100rpm.

Car is an auto, in 'D' idle is 800rpm.

I let the car warm up for over 10 mins before driving and the problem didn't occur.

Would still like to know what that component is... 

cheers,

JohnH

blind_elk Grand Master

blind_elk

Posted
Posted

The component is the cold start valve. Basically bleeds air when cold, until a bi-metal strip closes a "gate" inside the centre bit. Strip is heated by power through the connector on the underside.

This problem is with my old dizzy? Try adjusting the timing a bit. spec is 10 BTDC @ 750 rpm in "N"

jrh001 Proficient

jrh001

Posted
  • Author
Posted
The component is the cold start valve. Basically bleeds air when cold, until a bi-metal strip closes a "gate" inside the centre bit. Strip is heated by power through the connector on the underside.

This problem is with my old dizzy? Try adjusting the timing a bit. spec is 10 BTDC @ 750 rpm in "N"

I think the dizzy is OK, the car's running fine otherwise. For some reason, there's corrosion on the outside of the valve (and nowhere else). 

gallery_61769_3367_17031.jpg

Thanks for the reply,

JohnH

noddle Rising Star

noddle

Posted
Posted
I think the dizzy is OK, the car's running fine otherwise. For some reason, there's corrosion on the outside of the valve (and nowhere else). 

gallery_61769_3367_17031.jpg

Thanks for the reply,

JohnH

The "orange crap" is to secure the screw / nut from moving, the screw to adjust the hole opening size (for cold start air bypass)

Nigel

jrh001 Proficient

jrh001

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The "orange crap" is to secure the screw / nut from moving, the screw to adjust the hole opening size (for cold start air bypass)

Nigel

Ah!... it's supposed to be like that.

Thanks Nigel,

JohnH 

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