1994 Astra 1.8 16v

[corturbra]

Hi

I have a 1994 Vauxhall Astra 'M', 1.8 16v, Ecotec engine with DOHC + Multi Point Injection.

It has a bit of an erratic idle issue..... when I am accelerating through the gears and dip the clutch to change gear the revs stay/go up to 3000 rpm, if I leave the clutch in the revs after about a second delay drop down to 1100, stay for a second and then drop to 500 and then up to 900.

Also stopping sometimes the revs 'idle' between 500 and 1500 and then the engine will cut out. It always starts without a problem.

I've serviced it, changed the timing belt, run some fuel injector cleaner through, but with no luck. Anyone any ideas?

Thanks in advance for all your help.

[larsen_huw]

corturbra,

I know little about fuel injection and less about Vauxhauls .... but from listening to people discuss their problems with old Fords i can offer this:

Do you have an ISCV? That's Idle Speed Control Valve in English! :)

It's located between the air intake and the injection system. Have a look in your manual to try and find out if you do ... failing that, ask a mechanic to point it out to you.

Take it off, take it apart and give it a damn good clean. Then put it together, remount and hopefully all your idling problems will be over.

Bear in mind that all this comes from knowledge of old Sierras ... i don't even know if your car has an ISCV and if it does if you can dismantle it.

If at any point you don't feel confident, go see a mechanic to do it for you.

[corturbra]

Hi Huw

Thank you for responding.

I take it that the ISCV is the same as the IAC (whatever that stands for...) valve? Looking back through the previous owner's garage invoices, it's been cleaned a couple of times when one of the faults listed was poor idle speed, and replaced at 28,000 (now on 72000 miles).

I have a Haynes Manual for it which I think calls it something else... but I think I know where it is, but will get the wife to flutter her eyelids at the local Vauxhall dealer to confirm... :D

Is there any special cleaner I need? I have some Carb cleaner in the shed.

Thanks again for your advice. :)
JT

[larsen_huw]

I've always had petrol recommended to me as the best thing to clean it in.

[corturbra]

Originally posted by larsen_huw
I've always had petrol recommended to me as the best thing to clean it in.

Cool, so drop it in the tank for five and fish out? ;) :D

Many thanks again for the good advice.

[larsen_huw]

Dunno what Vauxhaul ones are like ... but on the Ford one's there's several bits that need to be taken apart and cleaned seperately.

Old rags and some finest unleaded would be my recomendation (oh! and don't celebrate finishing by having a ciggie! :D ).

[cooldude69]

the problem is it being a ecotec all ecotecs have idle problems
it normaly is the idle control valve
i had simler probs with my vectra and low idle cutting out
what u need to do is take it of and spray or soak in carb cleaner
also clean the intake and and sorrounding pipe work
vauxhall also do a breather mod for £10 that helps with the ecotec