Engine Stall when on full lock

JCR1987

Hi all,

I've got a quick question about my fiesta. When i put it on full lock to the right to pull into a car parking space this morning it stalled the engine. I tested it to make sure it wasn't my driving and it did it again, and again when I was stationary. Any idea what could be causing this, and likely costs to get it fixed?

Cheers,
JR

Strider590

You need to spec more info.....

"Fiesta" could mean anything from 1976 - 2010, 6 generations of the car.

I'd place a bet on it being a newer model with Electronic PAS, in which case the current drain at full lock is causing an electrical system overload and stalling the car.
Most of us know that at night, when we turn to full lock the headlights dim slightly, this is due to massive current consumption as the motor tries to apply more torque to the steering. "Normally" the car would detect that it was at full lock and prevent this.....

Could be an alternator fault, a charging fault, a faulty battery or an EPAS fault.

JCR1987

Strider590 wrote: »

You need to spec more info.....

"Fiesta" could mean anything from 1976 - 2010, 6 generations of the car.

I'd place a bet on it being a newer model with Electronic PAS, in which case the current drain at full lock is causing an electrical system overload and stalling the car.
Most of us know that at night, when we turn to full lock the headlights dim slightly, this is due to massive current consumption as the motor tries to apply more torque to the steering. "Normally" the car would detect that it was at full lock and prevent this.....

Could be an alternator fault, a charging fault, a faulty battery or an EPAS fault.

Its a 2003 (version before the 2009 new shape) 1.4 fiesta zetec.

One other thing i noticed, which hasn't happened on any of my other cars, is when i rev the engine whilst i'm stationery, the revs go up, but then they come down and the engine almost stalls. It manages to recover just in time but i can hear it beginning to stall.

Hintza

Get it serviced. And as above check battery/alternator (but if they are the problem the car should not be starting pretty soon)

Lum

If you are at full lock and continue to push on the wheel, then the power steering will try to push the wheels further which can't happen. There's usually an unpleasant noise accompanies this, but I'm not sure if that's the case with the electric ones.

Even if you get the stalling issue sorted, stop doing this as you'll just wear out the power steering faster.

johnnyroper

as you have noticed the revs drop low after revving along with cutting out on full lock i would say getting throttle body and idle valve cleaned out will sort it out.

basically the idle valve is not operating fast enough to increase rpm when putting under load at idle by using max PAS.

[Deleted User]

Also it's not advisable to dry-steer as this can damage the tyres.

benham3160

Or, if you want the real answer....

If you follow your PAS pipes from the pump towards the front of the car, you'll find a sensor sticking out of one of the pipes, it'll be freyed and shorting out, or the wires will have snapped completely.

Just rejoin them.

Very common on the 1996-2002 Fiesta. Although I worked for Halfords, so according to Hammy I don't know anything.......

Regards,
Andy

mikey72

benham3160 wrote: »

Or, if you want the real answer....

If you follow your PAS pipes from the pump towards the front of the car, you'll find a sensor sticking out of one of the pipes, it'll be freyed and shorting out, or the wires will have snapped completely.

Just rejoin them.

Very common on the 1996-2002 Fiesta. Although I worked for Halfords, so according to Hammy I don't know anything.......

Regards,
Andy

You can't just leave it there.
What the sensor, and what causes the engine to stall on full lock?

benham3160

mikey72 wrote: »

You can't just leave it there.
What the sensor, and what causes the engine to stall on full lock?

The sensor is......

**drum roll please**

The PAS Sensor!!

It's essentially a on/off switch that activates when the pressure in the system increases, this sensor then works with the ICV to maintain the revs due to the extra load on the engine.

Really common on these, the wires seem to frey and snap, nothing a few inches of scrap cable and a bit of solder can't fix though, normally the wires are found flapping around down the back of the engine bay near the bulkhead on the OS.

Quite often the wires short on each other, leading to the switch showing as closed to the ECU, this in turn raises the revs, giving a high idle, and is often misdiagnosed as failed/sticky ICV or tracked TPS.

Again, I worked for Halfords, so if you ask Hammy I know nothing.....

Regards,
Andy

johnnyroper

benham3160 wrote: »

The sensor is......

**drum roll please**

The PAS Sensor!!

It's essentially a on/off switch that activates when the pressure in the system increases, this sensor then works with the ICV to maintain the revs due to the extra load on the engine.

Really common on these, the wires seem to frey and snap, nothing a few inches of scrap cable and a bit of solder can't fix though, normally the wires are found flapping around down the back of the engine bay near the bulkhead on the OS.

Quite often the wires short on each other, leading to the switch showing as closed to the ECU, this in turn raises the revs, giving a high idle, and is often misdiagnosed as failed/sticky ICV or tracked TPS.

Again, I worked for Halfords, so if you ask Hammy I know nothing.....

Regards,
Andy

assuming you are correct why would it also have revs drop low and almost cut out after pressing and releasing accelerator?PAS sensor cannot cause that aswell.

i still say clean idle valve and throttle body and see how it goes.