idle issues cold related i believe

[jamiej 0]

Hey Guys,

Can i pick your brains.

I have had my VR6 OBD2 1997 Golf for about 4 months now and it has never put a foot wrong, until this morning.

The Problem:

At first the car would not hold an idle at all, it would just die, with no real attempt to hold an idle, this continued for quite some time and i had to drive around resting my foot on the accelerator whilst waiting at lights/roundabouts etc.

As the engine got warmer the idle seemed to be holding (if a little high) but occasionally would dip below 400 RPM or it would go a little haywire and flit from 1000 to 2000 etc etc.

The last symptom of my problem is the more severe engine braking, whilst driving along, if i lift off fully, there is a definate stall before the engine coasts down, like on the old mk2s, if you stampt the throttle when cosating, there is quite a harsh jump from the enrichment, it feels bit like that, only its a harsh decelleration.

So ... do any of these problems scream out a certain failed part/ or common running issue.

On my old 205, there was an idle screw and (to me) it seems that if there was one on the VR (which im pretty certain there isnt), then if that was all clogged or something, that would explain the harsh decell and inability to hold an idle.

Please furnish me with your thoughts/opinions and suggests ... oh, and Merry Bloody Christmas.

Jamie

[russj249 2]

mine was kind of like that when my mass air flow packed up... best thing to do is get it onto VAG-COM to say what sensor it is.

[Moochalargo 0]

Could be m.a.f (mass air flow meter) which i believe is the bit between the air box and the air in take tube! the thing with wires going in to it. if not and im not sure we have them on the vr but culd be th e idle stabiliser valve. i know that was the problem on my mk2 gt when it went nuts!

[muttley 0]

I had this 3 weeks ago

Take out the air filter box and the maf sensor compeletly,

Give your filter a clean

Clean the maf sensor inside where the 3 very thin wire's are with carb cleaner and leave to dry.

Put it all back together

The idle will be a bit mad for a while and it will run a bit rich for about 15 mins and then it should be fine

Hope this helps

[muttley 0]

Forgot to say, The maf sensor doesn't like induction kits in this weather

Also check your plugs

[jamiej 0]

thanks muttley for that. i'll have a look when its not so bleedin cold !

it does have an eBay special induction kit which it came with, so i guess it could be a mixture of the MAF and the crappy induction kit, is it just because of the free flow being colder than the standard air box would cater for ?

I have changed the plugs recently so i wouldnt have thought it was that.

Any more opinions ?

[thegoth 5]

OBD2 cars don't use an idle valve, they have a servo driven throttle butterfly. If you turn the ignition on without starting the engine the system will reset/recalibrate itself. Takes about 15mins.

Carb cleaner is generally accepted as being too harsh for the MAF. Electronic contact cleaner is safer.

If you take the MAF off you might as well take the rest of the intake piping off and see if the TB particualrly oily.

[Moochalargo 0]

cool that answers the idle valve query! i am running a k&n 57i and have done for 5 years and its been ok in all weathers! if anything worse when it warm as it can drop the bhp due to breathing warm/hot air