David Lock

So was this a wind up or am I just so ancient that I had never been told this before?

We have an old Saxo that we took in for MOT and said the only problem was starting the engine when cold as it seemed to catch and then die on us.

Garage guy said it started perfectly for him and he did what he always does which was to get in and floor the accelerator once and then turn ignition and start in usual way. He said that was the standard way of starting cars without a manual choke - which I guess is 99% of most cars nowadays. He reckoned this was the way to get the auto choke to kick in.

I said I had never heard of this and I got a look like I was some old codger who still drove around in a 1950 Ford Prefect.

Now this wasn't some trainee mechanic but the owner of the garage and I can't see why he should be saying this unless there was some truth in it.

So:-

1) Is he talking bollox?

2) Was it just a wind up?

3) Is there really something missing in my "how to start a car" vocabulary?

Oh and starting seems better now btw

David

dpb

Sounds the wrong way round, ignition first.

But if it works better with his method.....

How much did he charge for this titbit info

Bubba po

I seem to remember that the handbook in my old Astra Belmont advised that this was the way to engage the "automatic choke".

Chip

Bubba po

This from a VW website:

ALi-B

iTrader: (1)

Yes and no:

On carburettor cars thats aren't a SU or Stromburg (eg Weber, Pierburg, Solex, Nikki, Mikuni etc), flooring the throttle does two things...pump extra fuel into the barrel of the carburettor from what is called a "accelerator pump" and if the carb has a auto choke, it also releases the tension off the throttle mechanism to allow a spring to engage the fast idle cam. The auto choke does two things, one is close a flap at the top of the choke of the carburretor (hence its name), the other is prevent the throttle from fully closing (hence the term "fast idle" ).

Anyone with a Weber DCOE equiped car will tell you give the pedal two or three pumps before starting the car when cold.

However:

Saxo has fuel injection, it has none of that. What that does is increase the injector duration and open the idle control valve more.

What it is is old and French and therefor not working quite right, so it need s bit of tickle on the pedal to overcome whatever is preventing the ECU to maintain a staisfactory cold idle. Its probably fouled up (low mileage, never thrashed?), as the early ones are single point injection so excessive carbon build up at the inlet soaks up the fuel and the idle control valves also go a bit dodgy.

Also on early Saxos...lift the accelerator pedal up to the top of its travel, silly as it seems but a bit of sloppyness in the throttle return springs prevent the ECU engaging the cold start idle routine properly. Did I say it was French?

David Lock

Wow. Amazing the stuff you learn on SN. Thank you guys

dl

Myles

iTrader: (40)

My mrs' 106, a relative of the Saxo, lost its throttle potentiometer setting when the battery died, we had to go through a 'throttle to the floor, key to last click, foot off, key off, start up' and that would calibrate it. If you didn't, it would start until you took your foot off the throttle then die.

Leslie

It was a standard trick with the older engines with carburettors to floor the throttle before starting and allow it to close again so that the accelerator pump pushes a bit of fuel into the intake manifold to give it a rich mixture for a cold start. Too much pumping however can flood the engine.

Les

nick172sport

iTrader: (6)

i remember them days les

pslewis

Yeah, us old boys remember when you had to press the accelerator to 'engage' or, more accurately, 'release' the Auto Choke flap on its spring - this would squirt neat fuel into the intake manifold AND close the choke flap.

After starting a 'blip' would settle the idle speed and open the choke flap a bit.

A press isn't needed these days at all - on anything!

David Lock

That was problen in a nutshell.

So once re-set there was no moe need for foot to floor before starting??

David

Myles

iTrader: (40)

No, it set the throttle travel I presume. No problem once started. Also, it would not need doing again unless the battery was removed again.

Neanderthal

iTrader: (6)

Ahh the good old days of manual chokes!
I remember my first car having one and I'd convinced myself it would go faster if I left the choke out cause it would be running richer (1.0 Fiesta..)

Leslie

[quote=pslewis;10983984]Yeah, us old boys remember when you had to press the accelerator to 'engage' or, more accurately, 'release' the Auto Choke flap on its spring - this would squirt neat fuel into the intake manifold AND close the choke flap.

After starting a 'blip' would settle the idle speed and open the choke flap a bit.

A press isn't needed these days at all - on anything![/quote

So you are not a "pressed man" at all then!

Les