| This article was orriginially posted on the Votex
site, but is unfortunately hard to find. Because this is one of the better
diagnostic pieces that have appeared recently, I archived a local copy,
with all credit due to New Dimensions
and Votex.
I also edited the text a bit to increase readability. My additions are
surrounded by [ ].
Jan
Tech Tips
by Chris Lagattuta,
Autowerkstat
My name is Chris Lagattuta and I've worked at
ND as a technician for
the last ten years or so, before starting Autowerkstat. Over the years, I've had the great pleasure of
encountering some great technical mind bogglers as well as repair a lot
of problems that other people had trouble with. When you see the same cars
come in the door day after day, you start to see patterns.
I read a lot of your postings when I get home from work and often think
I can help out with the solution, except I never have time to write. So,
I wanted to dump a whole lotta stuff I accumulated over the years in hopes
it can solve some driveability problems for you.
VR6
VR6's--very few driveability problems overall but here's some tasty stuff:
idle problem #1 is caused from vac hose (7mm smooth rubber one on right
side of engine by #1 plug) that purges the fuel vapor canister. It is formed
like an "s" and melts on manifold.
I highly recommend using no other spark plug except the ngk or Bosch
dual electrode ( cant remember the #). I have seen it clear up slight idle
problems in a jiffy. Always use the factory tool to remove plugwires- ANY
cuts or rips on the boots will cause a short to ground from your high energy
ignition system. You can feel it when you are pushing hard on acceleration
as a "buck", or at idle as a "tick". Look at the car running in the dark
down at the plug holes to see it jump, especially in damp weather or spray
misted.
[Note: Spark plug wire resistance should be about
6k Ohms, give or take a few k Ohms. When I check mine, I had two that were
open. NOT GOOD. The reason the car still ran was simply because the
spark can jump multiple gaps. Jan]
Be really careful if you have Ram Air or K&N filters and you clean
them. After you oil them, let them dry thoroughly! I have seen two cars
that got excessive oil on the Mass Air Flow Sensor and made the car run
too rich. There is absolutely no way to clean the hot wires of the unit,
so if it happens to you, remove the offending filter until it is dry and
drive car a bit, starting and stopping engine so the inherent burn off
cycle can clean the wires off itself. Throttle position sensors can also
cause idle fluctuations but it is rare. You really need the VAG 1551 to
check the live readings. The dvom wont do.
Last tip for the cooling system-VR6s run HOT. Change your coolant and
install a low temp fanswitch(remove the battery to make it easy). The thermostat
is also a good idea-but I only recommend it if you have over 60k and you
replace all three pcs of the plastic thermostat housing. These things leak
like crazy! replace all the seals and don't use goop on any of it except
at the mount to the head( I prefer aviation sealer - the brown stuff in
the little can) Anyway, the fanswitch cycles the fan sooner and longer
and end result is that your gauge which normal reads about 230 can drop
as much as 10-15 degrees. It seems that all the car's gauges read a little
different.
Chris Lagattuta
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