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General Information => General => Topic started by: srgtlord on March 17, 2012, 03:31:22 am

Title: No idle speed boost on early pumps?
Post by: srgtlord on March 17, 2012, 03:31:22 am

I noticed a significant change in how my car started with a pump with idle speed boost and without. With the new pump and the cold start cable pulled out its almost as if the cold start lever does nothing at all. Does it actually do anything?

Title: Re: No idle speed boost on early pumps?
Post by: R.O.R-2.0 on March 17, 2012, 03:43:48 am

Quote from: srgtlord on March 17, 2012, 03:31:22 am

I noticed a significant change in how my car started with a pump with idle speed boost and without. With the new pump and the cold start cable pulled out its almost as if the cold start lever does nothing at all. Does it actually do anything?

on old pumps, the cold start advance is just that.. a mechanism to advance the statis timing of the pump 6* over the base line setting..

it has absolutely NOTHING to do with idle speed. it can not make the idle increase, because it has no connection to the throttle like a modern pump..

only thing you will notice when you pull the cold start cable, if your engine is timed properly, is that your engine will sound just a touch more rattly, but thats it..

Title: Re: No idle speed boost on early pumps?
Post by: bajacalal on March 17, 2012, 09:12:14 pm

I have a 1985 1.6 TD which I think is the last year of pumps that did not use a cold-start throttle increase, just timing advance.

If the engine is really cold it makes the engine run smoother and smoke less. If the engine is warm, it really doesn't do anything... but then why would you pull the lever? And yes, it makes the engine clack more.