Help i am going mad !

I have a 2.5 running at 1 bar on a hybrid vf28 all the extra induction kit , front mount etc etc ,full decat , running on a ecutek remap , 6 speedbox .Been having idle problems for months now the garage i go to have replaced 7 maf sensors yes 7 telling me that is the problem due to an induction kit , the last 3 replaced made no differance upon fitting , so i have changed garages now and the new garage popped off the icv .....idle control valve and it was totally gunked up with black stuff and was totally seized . So we went the route of replacing it at a cool cost of 255.00 notes yes £255.00 for a tiny sensor.

Well it ran perfeck and i drove home when i got home jumped out the car i could here a sucking noise which was coming from the icv so i removed it and found there was no rubber on it ! So i placed the rubber ring and refitted it started the car and yes the problem was back !!! So i removed the ring etc etc ran the car and again all perfeck but a sucking noise???? refitted the rubber ring again no sucking noise and the car idle was just up down up down hunting .
I then removed the vaccum hose off the dump valve and the problem resolved itself . Replaced the dump valve vaccum pipe and hay presto up down up down hunting again ?????? i even replaced the dump valve for another again no differance , it will idle ok for a while when driven sensibly around town but when given some welly it totally stalls upon stopping . My lamba is up and down as i have a delta dash display but runs around 00.325 but sometimes while being driven shows 000000, when it stalls it does show 000.325 which i have been told is ok , its up and down from zero to 000.825 like yoyo could it be the lamba sensor. Please can anyone help . Forgot to say also did also have probs with the advance multipler reading but the garage says it runs a max of 4.3 volts at 1.bar and has settled now after being delt with . please help anyone

 

bump

 

have you checked for air leaks from inlet gaskets and vac hoses etc?have a spray around with some carb cleaner and see if revs increase
might be worth checking the throttle flap for black carbon gunk closing up the preset air gap between flap and body of housing
also have you noticed any black smoke from exhaust?

 

It is running very rich i have noticed , lots of black soot when started up by a wall . Garage says it is very running rich to.

 

Think you will fidn a few motors leave a little black soot on the wall on startup, running a little rich is not a major concern the only way to check for sure is via a widband/ co/hc test or have the map checked over.

From what you say above the gardage fitted a new icv and left the inner valve of ? which when you got home you noticed. This i would take up with the fitter as it sounds like the problem was there direcltly after replacment.

How does it run when cold ?

 

It runs like dream when cold and when it comes of the choke it then starts to play up . Idle just hunts up down up down , as i said when booted it just stalls on stopping .

 

I would take a closer look at the icv check the small filter plate behind it is clear and not causing any problems and it is not sticking. Also check the connections to the loom and back to the ecu make sure it’s seeing the correct voltage. Also might be worth looking at the map sensor...