Map sensor maybe?

I believe the SPI has a switch somewhere near the gas pedal, so when the
pedal is not pressed down (engine idle), this switch tells the ECU to keep
the engine in idle.

Maybe worth checking if that switch is still OK?

Bye, Ray

These are one set of symptons for a leak in the Manifold  Air Preasure
(MAP) sensor.  The sensor is actually located inside the MEMS box (6
inch square aluminium box usually located near the front clutch side of
the engine bay with a great wad of wires coming out the bottom).

There is a thin plastic tube that comes out the back of the injector
body towards the firewall.  You will need to remove air cleaner to
access it - if you have the standard air cleaner then there is a second
tube from the air cleaner box that leads to another point next to the
MAP line that will help you find where it connects.  This tube goes to
a small black plastic box a little bigger than a match box (an oil trap
that is usually mounted near the clutch master cylinder), then a second
tube goes from this box to the bottom of the MEMS.

Check the rubber connectors on the ends of these tubes are not split or
perished, and that the tubes are firmly connected so as to not leak.
Also check that the tubes haven't been crushed or broken.

Another proble is when oil or fuel gets into the sensor inside them
MEMS.  This why they have the separator on the line, but sometimes it
still gets past it.  Take off the tube between the MEMS and the
separator and blow through it and check that no liquid comes out.  If
there is, dab an absorbent rag or paper towel on the tube's connector
at the bottom of the MEMS and try to draw out any fluids that may be
inside there.

John in Oz