Ford Scorpio Forum - Print Page


    
      
        Ford Scorpio Forum
        (https://www.fordscorpio.co.uk/cgi-bin/yabb/YaBB.pl)
      

        General >> Give/Need advice to/from others >> Stalling with hot engine
        
(Message started by: Pegasus on Apr 16^th, 2005, 6:21pm)

Title: Stalling with hot engine
Post by Pegasus on Apr 16^th, 2005, 6:21pm

Hi All,

can anyone answer this:

Ever since I've had the car (1997,24V, bought 2001, with 28k-now 52k), when I start off after being parked for 30-90 minutes and I'm in a car park or similar so I'm really just moving on impulse power (idle) it stalls after a few seconds. Doesn't stall if I just sit there though. When I fire up again the fault doesn't recur.

The nice, friendly service man at the local Main Dealer (the ones who dont change plugs etc) said he had an idea what it might be (a sticky valve?) so bring it in - it'll only cost £70 to look at it - right!!

It's not really a problem but is embarrasing when it happens and its niggling me. Waders :-* ran an ODB scan a while ago and couldn't find anything to suggest a fault.

Any ideas greatly appreciated.

Thanks

Pegasus

Title: Re: Stalling with hot engine
Post by ren on Apr 16^th, 2005, 8:59pm

Hi
it happens with mine at times most
embarrasing as autos aint supposed
to stall and then itll start next turn of
key and run as if nothing happened

Ren

Title: Re: Stalling with hot engine
Post by Eric_R on Apr 17^th, 2005, 8:59pm

Pegasus,
Did Waders run a check on the Enhanced codes as well as the Standard OBD ones?

You really need another scan - but looking at sensors instead of just codes. There are some issues that need looking at. On the Granada 12V this was often caused by the Idle Air Control Valve (IACV) - cleaning it often did the trick, but our 24V Cosworths are less susceptible to this.. You might try cleaning out the AICV though - it's easy to take off and put back and does no harm.

However, with the Scorpio Cosworth this symptom is often caused by:
TPS - The Throttle Position sensor (TPS) becomes worn and the programming loses the position of the throttle so that the mixture is not enriched in time to maintain combustion when the throttle plate opens.
HO2S sensors - these can 'flatline'. If one does so then fuel lamda control switches both banks based on only the other HO2S. This can also cause a weak mixture on one bank and hence the stall.
An air leak - the 'valve' that was mentioned may have been the PCV - the Positive Crankcase Valve - this allows blow-by gasses to be drawn from the crankcase by the inlet system, normally through a pipe into the air filter.
EGR valve. The vacuum-operated valve at the rear of the inlet system can sometimes 'stick' and let in unwonted exhaust gas.
EVAP system leak - the vacuum reservoir is kept open to the inlet system when it should not be in order to compensate for a leak in the EVAP system. Other leaks in the vacuum system can also produce unmetered leaks.
If you could meet with an OBD-equipped owner I could suggest some checks to run.
HTH

Title: Re: Stalling with hot engine
Post by Pegasus on Apr 18^th, 2005, 12:59pm

Wow! thanks for that Eric.

I aim to be at the Kent meet this Sunday (24/4). With luck someone will be able and willing to scan the system.

Cheers,

Pegasus