Afm Mixture Screw

[skinner2k3 3]

Hi All

 

I removed and cleaned the adjuster screw on the AFM of my 1.9 205 GTI, gave it a good clean and sprayed some carb cleaner through the hole. Trouble is I didnt make a note of how many turns in it was, now I have lost the setting. I recall you wind it in until the engine cuts out then back it off a number of turns, but cant remember how many!

 

Sorry if this has been asked before, I have tried the search function .

 

Also, where is the article on AFM tracking? I can't find it in the articles section.

 

Sorry one more, on the lower engine mount which the o/s drive shaft runs through which of the bolts which attach it to the block is meant to be the short one?

 

Thanks guys.

 

Ben

[Guest javars]

Cleaned mine out last night, and turned out 2.75 turns from all the way in. Re adjust when upto normal temp.

Steve

[skinner2k3 3]

Cheers Steve

 

I dont have a CO meter so I dont think I will be able to set it up very well, or is there another way?

 

Ben

[Guest javars]

Sorry didnt read the thread right, thought it was the idle screw & yes you need a C02 meter

[C_W 3 1 Cars]

You don't need a CO meter IMO, you just screw it fully in then unwind it until the idle starts to faulter then just wind it in a touch (with engine up to temperature).

[Rob_the_Sparky 9]

Oh and it can be completely different from AFM to AFM...can always tweak it at the MOT station should you need to.

[Higgy 0]

You don't need a CO meter IMO, you just screw it fully in then unwind it until the idle starts to faulter then just wind it in a touch (with engine up to temperature).

 

Not sure on that especially for passing a MOT. My Mi 'seemed' to be running fine, but the CO was 8%! when it was measured. I was turning that screw for ages to get the CO down

 

But saying that, if you know the CO needs adjusting (like I did) you just tell the MOT tester and bring a screw driver along with you

 

Higgy.

[skinner2k3 3]

I would take it to a garage only its not road legal. At the moment I am not looking at making it MOT'able, I just want to get it running properly/better!

 

All I really need is a method of getting the mixture somewhere near correct. Like what C_W has said. Just so I know I am not massively under or over fueling it.

 

At the moment it doesnt want to idle smoothly below about 1100 rpm, if I wind the idle down to 800 ish the engine shakes quite violently. I am going to try and give the car a good check over this weekend, clean the breathers, check the SAD, possibly check the state of the resistance track in the AFM (depending on how a trial run on a knackered one goes), clean the throttle body and try and double check the timing.

 

Ah, one other thing...could someone confirm the serial number on a 1.9 distributor, I have changed the head and forgotten which dizzy I should use. I have one of each!

 

Thanks guys

[C_W 3 1 Cars]

I would say all you're doing is setting it so the engine runs at it's weakest without start to idle roughly, this should normally be somewhere about right.

[Rob_the_Sparky 9]

Make sure the ignition timing is right when trying to get a stable idle.

 

Oh and you are aware that this screw only controls the idle mixture, normal running mixture is not readily adjustable (can be done but not intended by Pug).

 

Rob

[skinner2k3 3]

No, I hadnt realised that the screw only controls the idle mixture. Not so worried about it being smack on now.

 

I will just get it idleing as smooth as possible and leave it alone then.

 

Thanks

[Revla 2]

Oh and you are aware that this screw only controls the idle mixture, normal running mixture is not readily adjustable (can be done but not intended by Pug).

 

Just curious Rob - how do you do this????

 

Trev

[Rob_the_Sparky 9]

Normal way is to adjust the AFM spring tension or you could use an adjustable fuel pressure regulator (or a rising rate one) or spag in a variable resistor into the the ECU (part of what the "chipped" Jetronic ECUs have done to them).

 

Rob