can any body tell me what the rubber bung does on top of a v8 engine
I have had some problems with the running of my 4.2 supercharged
I found it half hanging out !!!
many thanks
dave

Any pics of the bung? RRS SUPERCHARGED, 22 INCH ALLOYS, JAVA BLACK, FULLY COLOUR CODED
EVERY POSSIBLE SOFTWARE UPDATE INCLUDING - BLUTOOTH UPDATE, SATNAV ON THE MOVE, CLOCK ON DASH, 3 CLICK FLASH, GEARBOX RESET, COMPRESSOR UPDATE AND SUSPENSION LOWERED,
BLACK CODE RE-MAPPED, AUTOBIOGRAPHY'D, NEW EXIDE BATTERY, NEW DENSO ALTERNATOR

A wider engine pic would be good.


Looks to me like you are missing the supercharger!

I'm pretty sure it's just a plug.

What's the engine not/doing ?

on start up the engine revs to 4000 rpm for a couple of seconds and then back down to appox 450 rpm she is miss firing and I have lack of power ever since I change the supercharger (I had a knocking noise top end I took the top off the charger and found shinny metal on the veins suggesting the veins were hitting each other hence the knocking noise)

Click image to enlarge

The knocking could well have been the coupler. The tensioner spring goes weak in them, so when the engine is at idle you can get a knocking sound. This is due to there not being a constant load on the pulley.
The veins will usually be polished on the edges due to the airflow and tight tollerances. You're more looking for scouring along the walls of the charger and notching on the edges of the veins.

Are you sure it hits 4k on startup ? The engine has an auto choke that will take it up to around 11/1200rpm for a few mins then drop down to about 650rpm.

The best way to move forward will be to pull the fault codes and see where that points you. If the engine is hitting 4k and then misfiring I would think it's either overfueling or the pedal rheostat (or a combination of both). It may be giving a false reading to the cpu, causing the throttle to go up. You could possibly test by unplugging it and checking for even/smooth operation by putting an ohmmeter on the leads.

No idea how many miles yours has done, but the spark plugs need changing at 100k.

hi thanks for the reply I am in the process of putting it all back together now with the old supercharger I have got a brand new throttle body top the part with the electronics on it hopefully this is what you mean by the pedal rheostat. the car its self has done 125k I don't know the condition of the spark plugs as I can not move them (don't want them breaking off on me )have tried spraying wd40 down the reassesses plus normal oil to see if this frees them up (no joy)

Click image to enlarge