V6 stalling/poor running

[nixoro]

Could a partially blocked cat be contributing have read stories it can cause problems. :-/

Only you mention eggy smells

[stuvaux]

the idle valve does seem a little loose since i cleaned it

the problem did start two days after i cleaned the IAC valve

could it be the seal then?  there is sometimes a short hissing sound after switching off the car - but it stops before i get chance to check it.....

stu

[stuvaux]

someone else has mentioned it could be a blocked exhaust...

the problem is very intermittent as well   there is no real pattern to when it starts

also, while the idle problem is there, it seems very flat up to 3000 rpm

stu

[nixoro]

someone else has mentioned it could be a blocked exhaust...

the problem is very intermittent as well   there is no real pattern to when it starts

also, while the idle problem is there, it seems very flat up to 3000 rpm

stu

Its a strange one, I personally wouldn't know what to best suggest other than checking the breather system which from the sounds of it you already have.

Your saying its gutless as in no pressure felt through the accelerator till over 3k rpm is that right.

[Marks DTM Calib]

Next step is to check the inlet and vaccum system......is the plenum loose, is the large brake servo vac pipe all ok with no holes rubbed through it (check where it passes close to the aircon pipe).

Are the smaller vac pipes all ok.....

Are the breathers that connect to the rear of the plenum all there and without damage.

[stuvaux]

i swapped the IAC valves back over today - with the old one on there, the car would not start at all

i then put the other one back on, put some sealant round where the valve enters the inlet - seemed to cure it for a bit, then it came back

does this mean its somehow linked to the IAC valve still?

stu

[stuvaux]

yes, its like there is no pressure hardly until 3000 rpm, its just flat

breathers on back of plenum all fine, no damage

vacuum pipes all connected and seem in good condition

[nixoro]

I know you have reseated the ICV could it be possible the connector isn't connected properly, usually there is some kind of clip that holds the connector on.

[stuvaux]

just re-checked breathers etc.

all seem fine, connected, none split/rubbed through
plenum tight

stu    

[stuvaux]

its the rubber part going into the plenum - it seemed a bit loose when i re-fitted it
there is no connector on there
i put some instant gasket on it to try and make a tighter seal

stu

[nixoro]

its the rubber part going into the plenum - it seemed a bit loose when i re-fitted it
there is no connector on there
i put some instant gasket on it to try and make a tighter seal

stu

My mistake regards the connector I thought the V6 ICV would have one just like the 2.0

[stuvaux]

its a pity it doesn't - might make for a better seal.......

[stuvaux]

can't see any problems with the breathers
vac pipes def all seem connected ok

what else could it be now???!

thanks,   stu

[stuvaux]

mark, will i need to strip down the inlet etc. now to make sure the breathers etc. are all as they should be?

or is there some other possibility?

it definitely happens on both lpg and petrol
the car does not only stall when stopped, revs drop very low and it has cut out at around 20mph
power is definitely down below 3000rpm when the problem starts
its never happened when the car is cold - only after at least ten minutes of driving

does any of the above help?   i am literally pulling my hair out now with this one!!!
help!!!....................

stu

[Marks DTM Calib]

I would certainly consider removing the plenum to allow inspection of the injector connections, plenum Orings and the fuel rail etc....

Worth removing the breather bridge etc from the plenum to check its clean and clear and that the seals are all in good nick.

I assume there are no splits in the inlet pipe work.....can you pinpoint the hiss whilst the engine is running....