re: strange warning in 90q

[Nathan Belo <belo@eskimo.com>]

On Fri, 27 Sep 1996, A. D. Morris wrote:

> >From: todd candey <tcandey@wwa.com>
> >Date: Fri, 27 Sep 1996 10:25:23 -0700
> >Subject: strange warning in 90q
> >
> >Hi all, I had an interesting thing happen last night in my 90q
> >
> >While driving home, I stopped at the grocery store and all was fine.
> >
> >Come back out of the grocery store, get in the car and start driving
> >as usual, then in traffic, the water temp warning light in the
> >autocheck display came on. It was red instead of yellow, indicating
> >that ther was a problem.
> >
> >This light went out after about 20 seconds.
> >
> >I looked at the temp guage and it was normal, about midway between
> >cold and hot. Since I was about 1.5 miles from home and the temp was
> >normal, I drove it to the house. I got out and checked everything
> >over, and found nothing wrong, coolant level was good, no signs of
> >leaks anywhere, no noises from water pump etc., no steam....
> >
> >What gives?
> >Anybody have any ideas?????
> >
> >TIA,
> >- -- 
> 
> My ('88 90Q) temp gauge is flakey, and only works when it decides to, 
> so when that happened to my while rolling down I-10 at 75 mph this 
> summer (In Arizona) with the outside temp around 110F, I got really 
> concerned.  I pulled over, poked around, and found everything okay.  
> This scenario repeated about a dozen or more times, with never any 
> other signs of durress.  (Working on the car during the summer is 
> _not_ my favorite pastime)
> 
> After about a month, it never re-occurred.  Some Q-listers have
> suggested that contacts on the temp senders can have problems - try
> cleaning them and see if that helps.  Your car does have *different* 
> sensors for the gauge and check system and ECUs - four in total.
> 
> -----------------------------------
> Allan D. Morris
> Phoenix, AZ
> allanm@primenet.com
> 1988 90Q
> -----------------------------------
> 
I had what I thought was a faulty sensor, but I was wrong.  I would turn
the car off and check the "burp/expansion tank" for coolant and it would
seem fine.  I decided to check the coolant when the car was running and
the coolant was low.  You don't open the burp tank when the car is running
or hot or you'll get burned.  When I shut the car off the burp tank would
fill.  When the car was cool I added a 50/50 H20/coolant mix and the light
hasn't come on since.

Nathan Belo
'88 90 Q 145K
Seattle