cold start problem

[Act Daft]

On first start of the day the engine sounds like its hunting for fuel,engine revs drop off as though its going to stall and then pick up again, only for the first 30secs to 1 minute after that idle is perfect and car runs and accelerates lovely.
Your thoughts on this would be most welcome.

Thanks Tim

[pacman1]

Sounds normal to me.

[vampire222]

Try removing your cold start injector, does it smell rich too?

[Act Daft]

vampire222 said:

Try removing your cold start injector, does it smell rich too?

Not noticed it smelling rich
Thought about cold start injector but wouldn't that be over fueling? seems to not be getting enough so almost stalling.

[RCK974X]

if it's a V6, it could be the cold start/enrichment unit at the front - it is both electric and water heated. They can wear after a while and get a bit leaky.... although it tends to affect hot running too when that happens..... just a suggestion.

The electric connection on the top often gets dodgy as it gets temp cycled a lot. WD40 or equiv helps a lot.

[Act Daft]

(V8 350) It starts easy enough and my understanding of the cold start is that its only working when you are cranking the engine and once you release the key to the run position it stops.
Out of curiosity gonna try starting with cold start injector disconected and see what happens.

[uglymug]

My 350i is exactly the same. Before I rebuilt the engine, it would idle over at 1200 ish then return to normal without me having to do anything. But now I have to use a bit of throttle to keep it from hunting then dieing. I have got used to it and I only need to do this for 3 to 4 mins, then it sort of gets into its normality and is good from then on. Have checked all wiring / tubes / pipes etc but cant find anything. CSI has always been disconnected and smells really rich, EAV all works , timing perfect etc etc . Would love to know how to make it better tho................................Mark

[Wedg1e]

Sometimes it's a compromise chaps, my car coughs and splutters like a 60-a-day smoker at breakfast when I fire it up but with a blip and a tickle it soon settles down ready for action.
Might be worth trying the old resistor across the coolant sensor trick. Or it could be excess fuel temporarily killing a plug or three until all 8 kick in. Could be several things really, who the hell wants a fire-breathing sports car to sound like granny's shopping cart?

[Act Daft]

Unlpluged C,S,I car fired up straight away and held steady revs also blew through vacuum advance pipe and cleared some crap out of that.
Ticking over at about 800 rpm when warm but seems to take its time settle after being reved up is that normal?

[mrzigazaga]

Now that the weather has warmed up a little does it start without this problem?..If yes then its probably something that aids the cold starting..Cold start injector blocked?...Extra air valve sticking??..If the idle returns slowly after revs maybe a sticking throttle cable..Does it do it if you blip the throttle quickly?..If its only doing it when warming up surely its not too much of an issue!!..Ziga

[350zwelgje]

Act Daft said:

Unlpluged C,S,I car fired up straight away and held steady revs also blew through vacuum advance pipe and cleared some crap out of that.
Ticking over at about 800 rpm when warm but seems to take its time settle after being reved up is that normal?

If it is a flapper, it has an air valve at the back of the plenum (hotwire have the stepper motor in this position). This could be the cause and unbolting it and turning the adjuster nut out to maximum could do the trick. Putting the adjuster in this position can be tricky as when it is not secured the nut can drop into the plenum... More information on this by Steve Heath in the wedge bible.

Rob

[Act Daft]

Sorted..... when I refitted vacuum pipe, fitted vacuum delay valve wrong way around, they maybe a problem with the vdv so as I understand it I can remove it and just use a straight through Vacuum pipe.