OT. Hunting engines

Two friends of mine left their vehicles for some time without using them,
one a Honda Civic and the other an "L" reg VW Passat.
Now they are MOT'd and back on the road both exhibit the same symptoms, the
engine hunts** when stationary instead of a steady tickover. After some
while, 30 mins, the Passat does tickover properly but if allowed to cool
down it reverts to it's hunting.
**slows down and then speeds up like you are constantly blipping the
throttle.
Any ideas?

--
Regards
Bob
1974 S111 SWB 2.25 petrol Hardtop (For Sale)
1987 90 2.5 petrol Hardtop (Stolen/found/but still not back)

> Two friends of mine left their vehicles for some time without using them,
> one a Honda Civic and the other an "L" reg VW Passat.
> Now they are MOT'd and back on the road both exhibit the same symptoms,
the
> engine hunts** when stationary instead of a steady tickover. After some
> while, 30 mins, the Passat does tickover properly but if allowed to cool
> down it reverts to it's hunting.
> **slows down and then speeds up like you are constantly blipping the
> throttle.
> Any ideas?
>
> --
> Regards
> Bob
> 1974 S111 SWB 2.25 petrol Hardtop (For Sale)
> 1987 90 2.5 petrol Hardtop (Stolen/found/but still not back)
>

1 - Choose a friend to be considerd 'your faviourite'.
2 - Sell him your S111
3 - Sell the other My RR

Mark
90 90
87 RR V8

"Mark Solesbury" wrote
>> Two friends of mine left their vehicles for some time without using them,
>> one a Honda Civic and the other an "L" reg VW Passat.
>> Now they are MOT'd and back on the road both exhibit the same symptoms,
> the
>> engine hunts** when stationary instead of a steady tickover. After some
>> while, 30 mins, the Passat does tickover properly but if allowed to cool
>> down it reverts to it's hunting.
>> **slows down and then speeds up like you are constantly blipping the
>> throttle.
>> Any ideas?
>
> 1 - Choose a friend to be considerd 'your faviourite'.
> 2 - Sell him your S111
> 3 - Sell the other My RR
>
The one with the Honda also has a Disco and as it's one of those Friday
Disco's (always something wrong) I don't think he would have another
Landrover at any price.

--
Regards
Bob

Bob Hobden wrote:
> Two friends of mine left their vehicles for some time without using them,
> one a Honda Civic and the other an "L" reg VW Passat.
> Now they are MOT'd and back on the road both exhibit the same symptoms, the
> engine hunts** when stationary instead of a steady tickover.

How long is 'some time'. It could be as simple as stale petrol.

They both make me think 'lambda sensor'. More so the Passat which
sounds like it may have a heated lambda sensor, but the heating circuit
isn't working.

If it's anything like some of the Fords we get here and the vehicle
battery went flat whilst unused the ECU may have lost or corrupted it's
calibration data (that it learns whilst being driven). Theoretically
the ECU will relearn as the vehicle is driven - it could take up to 1000
miles for it to learn enough to settle down properly.


--
EMB

"EMB" replied to
> Bob Hobden who wrote:
>> Two friends of mine left their vehicles for some time without using them,
>> one a Honda Civic and the other an "L" reg VW Passat.
>> Now they are MOT'd and back on the road both exhibit the same symptoms,
>> the engine hunts** when stationary instead of a steady tickover.
>
> How long is 'some time'. It could be as simple as stale petrol.
>
Couple of months at most.
>
> They both make me think 'lambda sensor'. More so the Passat which sounds
> like it may have a heated lambda sensor, but the heating circuit isn't
> working.
>
> If it's anything like some of the Fords we get here and the vehicle
> battery went flat whilst unused the ECU may have lost or corrupted it's
> calibration data (that it learns whilst being driven). Theoretically the
> ECU will relearn as the vehicle is driven - it could take up to 1000 miles
> for it to learn enough to settle down properly.
>

Thanks, is there a way to check it is the Lambda sensor, and where abouts is
one found on an engine, my vehicles don't have such things?
Do they cost much to replace?

--
Regards
Bob
1974 S111 SWB 2.25 petrol Hardtop (For Sale)
1987 90 2.5 petrol Hardtop (stolen, found and still not returned!)