2 replies to this topic

[t0mmy95]

Hi my 94 spi sprite has a habbit of cutting out. Sometimes but not always it does it when Idling and it sometimes does it when in stop start traffic or pulling up to a junction with the clutch out. If I give the throttle a tap as the revs drop it saves it and will idle fine I thought it might be the stepper motor as the vac pipes look fine and it dont do it when the throttle is open

[FlyingScot]

Read the pinned threads on here. Replace all the vacuum pipes and fuel trap before delving any further, the vast majority of problems reported on here end up being these items (even if initial denial about their condition persists).
Save yourself time, money and effort by starting with them - after all they are the main service items for the SPi system along with the fuel filter.

FS

[spiguy]

Agree with FS. If you haven't done it already, you should just renew these items and start off knowing that they are all good. Also as FS says, have a good read through the sitcky posts in this section which explain the workings of the various components of the SPi very well. Sprocket put together some superb information, and I get the feeling that people aren't making full use of it. if you read through it all, you will get a really good overview of how it all works and this will help you with fault finding and figuring it out.

 

As a very quick test however, if you want to get an idea if it is stepper related, wait until the car is at a decent idle speed - maybe during the warm up phase, say when it settles to 1000 RPM. Then pop the stepper motor connector off. This will effectively hold the pin that the stepper motor drives in this position. See if the car behaves better.