[urq] Ignition cut-out

[Ed Kellock]

Mine is an '85 but it spent a lot of time in SC near the coast.  The
back of the IC is very corroded.  I'll bet that there's similar levels
of corrosion in the fuse box too.

----- Original Message ----- 
From: "W. Bremer" <wbremer at maine.rr.com>
To: <urq at audifans.com>
Sent: Wednesday, February 16, 2005 4:12 PM
Subject: [urq] Ignition cut-out


If any of you with the ignition and tach cut-out problem have urqs
with the earlier fusebox (above the clutch pedal), the problem is very
likely to be the fusebox, either internally or particularly the pins
and sockets of the main power plug into the back of the fusebox.

Aside from the fact that that fusebox has to carry far more current
than it was designed to, 20+ years of living over possibly damp floor
mats (leading to some corrosion of the internal fusebox connectors
(and resulting high resistance), the main power plug (the middle of
the five big plugs into the back of the fusebox having one or two
large red wires feeding it) simply carries so much current that it can
heat up and deform (partially melt) the plug, causing occasional
disconnects of the power to the tach, ECU and dash warning lights.
Often (up to a point) give it a bit of time (one second) to cool and
it reconnects again, and the motor will fire back up.
A replacement fuse box is often step one, then getting the headlights
(and maybe the fuel pump) onto separately relayed and fused circuits
appears to solve the problem long term.

If you have a pre-1983.5 and your alternator light faintly glows at
night, or faintly illuminates in time to the turn signals, you have an
incipient problem with the fusebox and main plug sockets/pins, and
someday, the motor will just stop due to a heat induced disconnect
between the main power plug into the fusebox and the socket pins in
the fusebox.

Has not been a problem for the later cars with the under the hood fuse
boxes, but even these urqs are 20+ years old now, and almost anything
can fail, so it may be worthwhile to check those fusebox plugs and
spray a little Wurth Contact OL on the plugs and the pins.

My $0.02.
Bill
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