tick over problem Classic Vogue 4.2 lse

Hello, first post typically have a problem. When in park/neutral my motor ticks over fine but when in drive but standing still (idling) the revs are dropping off almost to stalling.
Recently had head gasket done at main dealer and de-coke hoping this might cure it but problem persists.
Any info apreciated, thanks stewarty

Doesit stall or do the revs just drop?Idle is about 800 on mine then drops when engage D until I increase throttle.If you leave it in D off all pedals what happens?Will it pull away with a little gas?

hi & thanks for reply......
to answer your questions:

• in park it ticks over @800rpm no problems
• engage D and revs drop to under 500rpm
• if I take feet of pedals it will then stall
• it really struggles to pull when I give it gas until the revs are well up then it drives fine

it has this problem cold or when warmed up, makes no difference.

cheers, stew

Have a quick look at this, might help. 3.9 and 4.2 are very similar, certainly I think the injection system is the same. Also do a search, there is plenty about idle and running problems with V8's.

http://www.landyzone.co.uk/lz/f8/v8-idle-stalling-66219.html

thanks a lot I'll try a few suggestions from link

Still looking at this problem. When I first got motor (8 yrs) it failed MOT on emissions so had a new air flow meter fitter which cured the problem.
Can someone please explain the relationship between this meter and tyhe MAF sensor, and where I'll find the MAF sensor. Is it a separate part and something easy and hopefully cheap to do? Also any calibration or adjustments to make afterwards? Thanks again, Stew