Cold start - pinning the throttle pedal
Discussion
First I'd heard of this, from an old EVO article on the guy's long term 4.3.
"Gaydon-era Astons have a neat trick, whereby pinning the throttle tells the engine management not to send fuel and sparks to the combustion chambers. So you can crank the engine over on the starter motor until the oil pressure warning light goes out, then stop and repeat the starting process in the usual way."
Does this still apply on 4.7s? As getting it wrong doesn't really bear thinking about...
"Gaydon-era Astons have a neat trick, whereby pinning the throttle tells the engine management not to send fuel and sparks to the combustion chambers. So you can crank the engine over on the starter motor until the oil pressure warning light goes out, then stop and repeat the starting process in the usual way."
Does this still apply on 4.7s? As getting it wrong doesn't really bear thinking about...
Yes it does. It's covered in the Owners Manual under the "Recommissioning after Storage" section [page 11.35 of the pdf of the manual for a 2013 car].
7. Obtain engine oil pressure:
7.1 Press and hold the accelerator pedal hard to the floor (this
temporarily stops fuel injection during cranking).
7.2 Fully press the brake (SportShift transmission) or clutch
(manual transmission) pedal down. Insert the vehicle key
into the ignition control and move through to engine start.
Allow the engine to crank until the oil pressure symbol in
the instrument cluster goes OFF (showing oil pressure
in the engine).
7.3 Set the ignition to OFF. Release the vehicle key and
accelerator pedal.
Important you don't let off the throttle pedal at all during this.
7. Obtain engine oil pressure:
7.1 Press and hold the accelerator pedal hard to the floor (this
temporarily stops fuel injection during cranking).
7.2 Fully press the brake (SportShift transmission) or clutch
(manual transmission) pedal down. Insert the vehicle key
into the ignition control and move through to engine start.
Allow the engine to crank until the oil pressure symbol in
the instrument cluster goes OFF (showing oil pressure
in the engine).
7.3 Set the ignition to OFF. Release the vehicle key and
accelerator pedal.
Important you don't let off the throttle pedal at all during this.
Definitely worth checking your Owners Manual for the correct procedure before attempting this. I’m fairly sure it doesn’t work with the later Bosch ECU although this may only apply to V12 engined cars rather than V8. I dread to think what would happen if the engine is cranked with the throttle to the floor and the fuel/firing etc are not inhibited at the same time. BRM.
Minglar said:
Definitely worth checking your Owners Manual for the correct procedure before attempting this. I m fairly sure it doesn t work with the later Bosch ECU although this may only apply to V12 engined cars rather than V8. I dread to think what would happen if the engine is cranked with the throttle to the floor and the fuel/firing etc are not inhibited at the same time. BRM.
The same kind of thought you get when you wonder what would happen if you press 'R' whilst travelling forwards at 70mph. You're sure they've put some kind of safety feature in to stop it engaging, but what if...I’ve used the process a few times on my 4.3 after it hasn’t moved for a few weeks. It often takes 10+ seconds of cranking for the oil light to go out, which leaves me wondering how much extra wear would be caused if I just fired it up with no oil in the crank journals, bores or cylinder heads.
https://www.youtube.com/watch?v=rSpEupXmh5Y
Mike states he does short periods of crank to not stress the starter, for V8 ASM his explanation starts at 10:00
Mike states he does short periods of crank to not stress the starter, for V8 ASM his explanation starts at 10:00
yeti said:
Thanks for confirming, can't see the car ever laying up for more than a month but good to know if the unforeseen happens...
By the time I get back to my car next week it ll be 4 weeks idle so I plan to do this, just to be safe. I ve done it before, when it came up on previous chats, but at that time it was not fully clear how long it would need to be idle to need to do it Ps- mine is 2009 4.7
To gain confidence, probably best to try when engine is up to temp?
In my V12 DBS its foot to floor on throttle, clutch in and crank. Engine just turns without starting which prevents any fear of oil starvation.
I would only do this after non use of say a couple of weeks.
Hey Lewis, long time no hear. You still got the DB9? I still have that watch I bought off you
In my V12 DBS its foot to floor on throttle, clutch in and crank. Engine just turns without starting which prevents any fear of oil starvation.
I would only do this after non use of say a couple of weeks.
Hey Lewis, long time no hear. You still got the DB9? I still have that watch I bought off you
Greathey said:
I thought dry sump cars have electric pumps that should pressure the oil even before starting the engine?
Ref. 4.7.
I don't think so, otherwise the oil pressure light would not delay going out.
Concentrate while holding the accelerator pedal down.
Even the slightest lift and you will get full revs.
This topic links in to modern cars with Stop/Start systems.
At the very initial moment of engine start, the oil pressure must be zero.
After thousands of unnecessary extra starts, will the engine still be in perfect condition?
AMTony said:
To gain confidence, probably best to try when engine is up to temp?
Careful. The ignition inhibit feature might not work when the engine is "hot". Not sure, though, I hasten to admit.The only way "to gain confidence" is to look into your CoC or DCS Build Specification Data or Technical Hub Vehicle Features and find out which engine type you´ve got. Knowing this you are nearly there! Now, just find out if your Aston engine is equipped with Visteon EEC-VI engine management.
Bingo. Simpo Two said:
The same kind of thought you get when you wonder what would happen if you press 'R' whilst travelling forwards at 70mph. You're sure they've put some kind of safety feature in to stop it engaging, but what if...
Apparently it pops the gearbox in to neutral, if going more than 5mph. Although, I can’t bring myself to try it, lol. John
Emilio Largo said:
AMTony said:
To gain confidence, probably best to try when engine is up to temp?
Careful. The ignition inhibit feature might not work when the engine is "hot". Not sure, though, I hasten to admit.The only way "to gain confidence" is to look into your CoC or DCS Build Specification Data or Technical Hub Vehicle Features and find out which engine type you´ve got. Knowing this you are nearly there! Now, just find out if your Aston engine is equipped with Visteon EEC-VI engine management.
Bingo. Go60 Jay said:
Apparently it pops the gearbox in to neutral, if going more than 5mph. Although, I can t bring myself to try it, lol.
'We're looking for a futile gesture Perkins...' 
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