Folks,

Could anybody please explain the mixture changes that occur as the standard
2.1 wasserboxer warms up to operating temperature? It is simply a matter of
the water temp II sensor saying to the ECU, "ok, we're at temp, lean it
out."

Here in Minneapolis the temp has warmed into the 50's. At that temp, when i
start my van, it is simply wonderful. Lots of power, especially in the low
end of the RPM range. What i mean by that is i can shift before 3000 and the
engine just pulls right out of the RPM hole smoothly.

However, after about seven to ten minutes, as the temp needle just begins to
move on the scale, this behavior stops and i need to rev to 3800~4000 if i
want the vehicle to continue accelerating when i shift to the next gear.
Accelerator pedal position does not seem to make a difference... on the
floor or 1/2 wide open... exact same sluggish performance until the RPMs
build.

It is like the "power band" simply moves up the tachometer as the engine
warms up.

I recently put in a brand new AFM and a K&N air filter. This has improved
overall performance (i'd like to believe), but, if anything, has put even
more of a spotlight on this cold/warm performance difference.

++++++++++++++++++++

Now for the admission (unrelated to above question)... i add this with
*great* trepidation (i'm putting my body armor on as i type): I posted a
while back that my radiator had started a slow leak. After dropping the
spare tire and really getting in up there i saw the leak was indeed along
the edge of the radiator. Well, as a temporary fix, upon the suggestion of
the local VW shop where i've had all my repairs done, i slowly put about two
tablespoons of "Silver Seal" into the cooling system after the engine was
fully up to temp.  The guys at the VW shop said "Silver Seal" is the only
stuff they'd even consider putting in a wasserboxer.

I kept the engine revving while looking up front.... drip... drip....
drip......drip.........drip........ then no more drips. I got out my IR
Thermometer and measured all over the engine and radiator, especially the
heads, looking for hot or cold spots that might indicate a blockage. About
300 miles later, all seems fine.

I will replace the radiator as soon as i pay off my most recent repair
bills.

So, i know my dad would be saying (shouting), "you put particulate matter in
your COOLING system! Are you NUTS?!"

I'm wondering what all y'all have to say on the subject. I may add a can of
"Silver Seal" to my roadtrip kit.

-jspeer

'89 Westy, "Mystery Machine"