Idle issue

[RobboVl]

hey all,
I originally thoght this problem was an issue with the spark plugs, but i have since changed them and it is still there..
okay, so when i pull up at a set of lights and let it idle i can feel sort of a miss-idle, and i can feel the vibrations through the car like the engine itself is jerking around (but not hard, you can just feel it.)
And it is not timed it can stop for 5 secends then start and keep on doing it every 3 secends..

Also it seems too stop when i put the car in nuteral..

let me know what it could be, cheers!

 

[Sabbath']

Fuel pressure regulator problem.

 

[harry3]

the correct way to set idle speed is shown in the workshop manuals and is complicated, you could try to find a VL workshop manual at a local library and photo copy details

 

[detox_nath83]

clean ur AAC (Auxiliary Air Control)valve mate. its probably gummed up.. as well as u throttlebody. u can cheat and use carby cleaner...

but i would part the plenum and flush it out with degreaser.. if u part ur plenum u will need a new gasket from plenum to intake runners

whats ur idle RPM?

should be around 750rpm u can bring it up slightly by adjusting the screw on the back of the plenum facing firewall.

Dont adjust the throttle plate resting point.

 

[RobboVl]

cheers guys, ill have a play around with what use said!
Yeah i have the gregories manuel and the owners manuel, and mny revs are sitting at about 850rpm.
is that too much?

 

[detox_nath83]

nah thats ok man. i rekon its the aac or dirty throttlebody though. i had the same problem about 2 years ago and this fixed it

let us know

 

[RobboVl]

The problem still exists and it has gotten A LOT worse,
its to the point were i cannot drive the car for more then 10minutes, it starts of fine then gets terrible.
i have gotten a new dizzy and distributer cap. and it still happens.

i did further inspection last night and i noticed the the spark plug number 5 clicks and you can see a spark jump out, i have checked the plug itself and it doesn't seem cracked. i tried to wrap the lead up with electrical tape to be a temp fix but that didnt work.
If i dont fix the problem with a new set of leads i dont know whats next.

let me know what i should do, cheers.

 

[Sik_Cordz]

just curious on how to clean the aac valve and is there a gasket between it and the manifold

 

[detox_nath83]

there is yes but should be ok.. make sure the pin is moving freely. u can go further when u remove the plenum to pull off the rear housing and clean in there properly. as a lot of blow by ends up in this area

 

[seans VL Calais]

a new set of leads will get it running on 6 cylinders again, does it blow out black smoke ? like its overfueling ? possibly coolant temp sensor, or cas but youve said you replaced that. also have you done a basic service on it ? fuel filter, air filter, etc.