Re: Rough idle and message to Loren (archive)

Rough idling when cold: Intake gaskets! (believe manifold is the word?) Had them replaced on mine earlier. I'm told a good way to test this is removing the 'beauty cover' and spraying start-spray at the gasket with the engine running. (a bit dangerous too). If the idle goes up, you have a leak.
Here is a intruction i copied in case you want to try:

OK, here is the info on R&R'�ng the intake manifolds. I will assume nothing
and take you through the process step by step (I may inadvertently leave
something out).

Removal:
1. Remove beauty cover.
2. Remove beauty cover brackets.
3. Remove mounting brackets for CPS's from front of engine. Remove brackets
from connectors.
4. Disconnect injector electrical connectors from injectors.
5. Disconnect electrical connectors from DK motors. Remove intake boots,
etc.
6. Unbolt and lift wire trough from top of engine. Move to side (no need to
remove coolant reservoir).
7. Unbolt fuel rails, disconnect appropriate fuel lines (caution: fuel under
pressure). Remove fuel rails complete with injectors. No need to remove
injectors from rail, now you only need to replace 12 o-rings.
8. Now you need the following tools for unbolting the manifolds: 1/4" drive
10mm shallow socket. Universal joint. 12" extension. Magnetic nut/bolt
retriever.
9. Using the socket set-up to access the difficult to see/reach nuts. When
the nuts disengaged from the threads, place the magnet on the nut and remove
the socket. This will prevent you from dropping the nut in the black hole
of the engine V. I also suggest that pieces of paper towel are placed in
the injector holes.
10. After all 12 bolts are removed, unbolt the supports from the plenum side
of the manifold. Remove the manifold leaving the expensive rubber block
gasket in place on the head. No need to remove the DK assemblies.

Re-assembly:
1. Clean intake sealing surface and rubber block surface.
2. Using Hylomar (sp?) or equivalent, apply thin layer to intake manifold
sealing surface.
3. Reverse removal processes.
4. HERE IS MY TRICK/METHOD FOR STARTING THE NUTS ON THE SECOND MANIFOLD.
Using paper shop rag/towel of suitable thickness, wedge the nut in the
socket so it won't fall out when lining it up on the manifold studs. Start
the nuts and tighten in stages evenly on all 12 nuts. It takes me about two
hours to do all steps (R&R) from start to finish not counting spark plug
changing, clean-up of parts, etc.

I hope I did not leave anything important out. Remember there is no need to
replace the intake gaskets unless the rubber insert is displaced and
distorted beyond help. The Hylomar will seal the intake better than new
gaskets alone. Do not use too much...you do not want to introduce excess
into the combustion chamber.

'Slack' over 100kph:
Could be the 'lock-up' on the (automatic) gear box disengaging. When you release the throttle over 100kph (try 130 or something), watch the rpm. When the 'lock-up' disengages, you see a rapid fall of engine rpm's. When this happens you could be hearing a small noise, nothing to worry about (in my opinion, i have it too).

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