Car Wont Idle When Cold

[acox99 74 1 Cars]

Iv had my 205 for about 2 weeks, and the car has never idled when cold, but when it warms up it idles at around 1200, the idle screw is wound in to keep the idle down when hot, as if you wind it out when its cold so it idles, it idles even higher when hot, iv tried to test the SAD and it seems to work, you disconnect pipes and the car stalls, i dont know if its wear in the throttle body, but the car has only done 90,000. Any help would be much appriciated as its driving me insane.

[Daxed 7]

You don't mention what engine is at issue.

 

Assuming std GTI, check the flexible hose from the bottom of the inlet manifold back to the SAD for airleaks.

[Simes 248 2 Cars]

Check the bolt holding the oil filler is in the plenum....otherwise this is a 'bit' of an air leak too.

[205*31* 0]

I think thats the way gti's are mate I have tried numerous SADs new spark plugs, dizzy cap and rotor arm given it a good service but still idles crap when cold once its warm after about 5min its fine.

[welshpug 1,657]

I think thats the way gti's are mate

 

Only tired worn out ones are like that.

 

 

sounds like as always it just needs setting up properly, possibly refurbishment or replacement of the AFM, they are the weak link of these systems.

 

 

SAD's are simple valves, they either work or they don't, as an isolated component they rarely cause issue, the system as a whole is what you should look at.

[DamirGTI 342]

Apart from said air leaks , check if the SAD heater element connector is connected on the SAD (black 2pin connector) .. if it is , unplug the connector from the SAD , switch ignition ON and check/measure voltage @ connector terminals .. you'll need to see battery voltage , or at least near battery voltage value ..

 

This the connector supply's voltage to the SAD heater element which is needed to fully close the SAD when the engine warms up to the operating temp , without this , it'll remain partially open during the driving on a flat straight road in higher gear , i.e. when the coolant temp. remains a tad down on the scale (as it's bolted on the cooling circuit , coolant temp usually closes the SAD a bit , but only when engine operates at higher coolat temp.'s say above 90C , under 85C the temp. wont be sufficient to fully close the SAD without the aid of heater element ..) .. it'll continue to raise the base idle speed on fully warmed up engine ..

 

Damir

[acox99 74 1 Cars]

Sorry, yes it is a std 1600, thankyou for the response, i wondered if it could be to do with wear in the tb as if you push the spindle the revs drop a bit, and it will idle with the idle screw completely wound in, guess that means the SAD is working, iv adjusted the throttle positon sensor roughly as i couldnt get a feeler gauge in there, and i have given it a full service, cleaned out the air flow meter and throttle body in the wash tank, i didnt know what the car ran like before i got it as i bought it with a broken belt, is there any other adjustments i can check when doing a 'tune up'?