Sailor24

Did you check to see if they did light on fire. I have checked a couple and one has not, I am at a lose why not?

pdudek

I did check and the liquid did burn .. I burned a few finger hair trying it out.

68FB

A word of warning - this is embarrassing to admit, but I tried the cardboard leak check and ended up sucking 2 litres of oil into the cylinders. I realized when smoke started pouring out the exhaust. So much oil drained into the bank 1 cylinders after I shut the engine down, it hydro-locked them and the starter couldn't crank the engine over. I ended up having to remove the bank 1 spark plugs and vacuum the oil out of the cylinders.

I was well aware of the risk of sucking oil up the plenum drain and oil separators drains so I had the hoses firmly clamped with tools specifically designed for clamping hoses - but the damn clamp on the bank 1 separator drain came loose. So be careful!

By the way, this happened because I took the easy route and disconnected the separator hoses at the valve covers and plugged the hoses. This meant the crankcase was at atmospheric pressure while the separators saw the high vacuum pulled in the plenum. If I had disconnected the separators from the plenum and plugged the holes in the plenum, there would have been no vacuum generated in the separators and no risk of oil ingress up the drain lines. The benefit of hindsight.

Also by the way, I don't believe you can suck oil up into the plenum with the separators still connected because the vacuum pulled in the plenum is transferred to the crankcase so no differential pressure exists across the three drain hoses.

I was worried about the cats being permanently contaminated but I have put a few hundred km's on the car since the fiasco and everything seems fine.

Another thought - with a leak-tight plenum, just before the engine stalls, you could be pulling 15-20" of vacuum in the plenum. That is creating a huge load on the plenum, maybe 3000-4000 lb. Seems to me there is a risk of collapsing or cracking the plenum since I doubt it would have been designed for this.

pdudek

Thank you guys for the help.

I received all gaskets last friday and started putting the car together over the weekend. Although I've taken the plenum off twice before I can't find or remember if there is a torque spec on the horns within it.
Can anyone help?

I ordered all gaskets starting from the throttle bodies, all around the plenum and up to the air filters. Hopefully that solves it.

Paul

68FB

No, there's no torque specified in TIS for those little nuts. They are supposed to be locking nuts so they just need snugged up. If they thread on too easily, the locking is worn out so use a dab of Blue Loctite thread locker.

pdudek

Thank you!

pdudek

Update:
I replaced all gaskets starting from both seal flanges on the throttle bodies to the O-rings between the MAFS and Air Filter. I snugged it all back up last night and took the car for a ride. At first everything was fine but when I started the car after I spend about half an hour at a friends it started to idle hunt again.

Not sure how to tackle this anymore. I'm thinking about dropping it off at a shop here next week when I get in touch with them.

Paul

TopEnd

Any updates for us?

__________________
2005 Mecedes Benz E55 AMG
2000 E39 M5 (totaled by drunk old man )
1997 BMW 540i/6spd (Sold to a looser)

1998 BMW M3 (sold)

pdudek

Actually, so far the issue hasn't come back yet.

I don't drive the car very much but I went through the cycle and that possibly did the trick! I will keep you up to date though and let you know if there are any changes.

Paul

Armonster

Bump -

I just bought a 2002 m5 and it does the same thing on hot starts, but hasn't thrown any codes. The idle bounces from 600-800 rpm for no longer than a minute. The lights in the dash flicker faintly with each dash.

The car idles normally at all times aside from the 45 seconds after a warm start. Again, no codes to share. Any thoughts? Thanks for the help.