dodgy fuel??

[kevtherev]

hi all
just been to the coast for a long weekend and only having bought the car a couple of weeks earlier thought it would be good to blast it out.
so for 2 weeks run the car on good petrol but only having a 1/4 tank or less : car is fine
decide to brim the tank so go to supermarket and fill up (taking advantage of points system)
next morning will it start? in a fashion yes but wont stay running stalls as soon as clutch is pressed for gear changes this goes on for 4 miles then its fine.
run it to the coast (200 mile) fine
next morning. same prob. few miles all is well again.
next morning, start it, take it to petrol station put 35 litres of good fuel in ie not supermarket go home again.
all is well.. 3 days later still all good
conclusion; crap fuel from supermarket. ( not stepper motor probs which i 1st thought )
just wondered if any 1 else has had similar probs with regards to dodgy fuel??

[Welly]

I have heard from other people that their car 'dislikes' cheapo petrol but it shouldn't be cutting out. I suspect the petrol grade is adding to an existing problem (like the idle control system).

There's a thread in the knowledge base about the petrol's idle problems have you checked it out?

[kevtherev]

not yet but gonna try and find that thread now thanks welly
it's just strange, i brim it with cheapo fuel and the next day problems. i also chucked half a bottle of redex injector cleaner in too would that cause any probs???

[kevtherev]

hello all
my problem is back again
seems the fuel wasn't to blame
just to recap: try to start car but it wont stay idling under its own steam i have to sit in it with foot on pedal to keep it running . when driving ,as soon as clutch is engaged the engine trys to /does cut out. obvously when clutch is brought out again it "bump starts" the engine and off we go . sorts itself out after a few mins/miles
i have read the thread on cleaning the stepper motor as suggested by welly (thanks)but i am now a little confused
is the stepper motor the same thing as the idle control valve??
will have a go at cleaning the stepper next weekend and will see how things go but it is an intermittent problem, can be fine for days and then...
thanks in advance for any replies

[mjb]

i have read the thread on cleaning the stepper motor as suggested by welly (thanks)but i am now a little confused
is the stepper motor the same thing as the idle control valve??

Yes and no

A stepper is a little thing which pushes the throttle butterfly open.
An idle control valve is a valve which opens up to provide a separate way for air to get into the throttle

So no, they're not the same, HOWEVER they do do the same job, albeit in different ways, of getting air into an engine when you ain't got your foot on the accelerator

In reality, ICV seems to be an acceptable term to refer to either