Fox T-Bird/Cougar Forums

Technical => Electrical Tech => Topic started by: amooset on October 28, 2009, 01:15:44 AM

Title: Heater core replaced, Yay! New problem, BOO!
Post by: amooset on October 28, 2009, 01:15:44 AM
I just replaced the heater core last weekend only to create another problem: A flicker in electrical power every 10 seconds or so while the ignition is in either the run or accessory position.  I believe it is wiper-related because the wipers won't return to the stowed/parked position, and the flicker in power doesn't exist while the wipers are running.  I am thinking there might be a loose wire somewhere but there are miles of wiring to look through.  I was hoping someone here has had a similar issue or at least has an idea where to start looking.

Also, I forgot to replace the nut that attaches the dash to the underside of the instrument cluster area.  Is this a critical ground point that may be causing the issue?
Title: Heater core replaced, Yay! New problem, BOO!
Post by: Beau on October 28, 2009, 03:42:58 AM
I dunno if this'll help your problem, but on each side of the center stack of the dash (where the climate controls, radio, dash cubby, etc all sit vertically) there's a ground wire, one per side, on the inside. It's in an area right behind where the ashtray sits on a consolette car.
I forgot to hook one up on my white car after I swapped dashes, and my electronics did some crazy funky stuff.

The terminals attach to the sheet metal "frame" of the dash itself, which is in turn grounded to the cowl area, i reckon.

Just a thought...hope it helps.
Title: Heater core replaced, Yay! New problem, BOO!
Post by: Haystack on October 28, 2009, 04:52:09 AM
My dad had this problem on his crownvic. He got a motor out of a cougar to fix it.

Luckily, someone has a write up for this.
http://www.coolcats.net/tech/troubleshooting/wipers.html
Title: Heater core replaced, Yay! New problem, BOO!
Post by: amooset on October 28, 2009, 07:19:33 PM
Well, I dropped the steering column down and replaced the nut under the cluster. I don't know if there was a loose wire or if that was actually a ground point, but it seems to have fixed itself.
Title: Heater core replaced, Yay! New problem, BOO!
Post by: vinnietbird on October 28, 2009, 08:09:06 PM
I didn't mind changing mine.If more members were really close,I'd change them for everyone for a hundred bucks each plus the cost of parts.
Title: Heater core replaced, Yay! New problem, BOO!
Post by: amooset on October 29, 2009, 01:59:48 AM
Quote from: vinnietbird;296810
I didn't mind changing mine.If more members were really close,I'd change them for everyone for a hundred bucks each plus the cost of parts.


I agree.  With the reference page on coolcats, I was able to finish in under 3 hours working casually and swigging a couple of beers along the way.  If the electrical issue hadn't crept up on me, It would have been a piece of cake.

Many thanks to Eric and others who contributed to the tutorial on coolcats!
Title: Heater core replaced, Yay! New problem, BOO!
Post by: tbirdsps on October 29, 2009, 09:41:05 AM
I dreaded changing mine.  I put if off and put it off some more.  Two years ago I decided it's time.  I had the dash out in an hour, changed the heater core, reinstalled the HVAC unit and had the dash back in an hour and a half.

I no longer fear that job.:burnout:

Dash out:
(http://img515.imageshack.us/img515/4876/sany0066pz1.th.jpg) (http://img515.imageshack.us/i/sany0066pz1.jpg/)
HVAC on the hood:
(http://img364.imageshack.us/img364/6537/sany0067wc9.th.jpg) (http://img364.imageshack.us/i/sany0067wc9.jpg/)
Title: Heater core replaced, Yay! New problem, BOO!
Post by: vinnietbird on October 29, 2009, 10:19:34 AM
The job is more mentally scary than actually hard to do.It's all about knowing what you're doing.After reading the Coolcats article and talking to Eric,I can do it in an hour or less.Granted,I didn't have a/c lines hooked up.When I install the a/c equiopmen,I'm going to swap the core again.Mine is good,but after 3 years,I might as well while I'm in there.
Title: Heater core replaced, Yay! New problem, BOO!
Post by: EricCoolCats on October 29, 2009, 10:36:07 AM
I was a heater core virgin until 1999 or 2000, when, of all cars, it dies in the convertible. Of course...the only thing I never use in that car is the heater.

IIRC, Zach stopped over and it was the first time I'd met him in person. He decided to hang out for the day whilst I changed out the core. The only thing I forgot was to hook up the small vacuum line to the main tee out in the engine bay. The system was stuck on defrost for several years until I redid the whole vacuum distribution system. Not like it really mattered for a convertible, but still.

So I'd known about doing the heater core swap for some time, and several people sent me pix and info over the years as well. Then I thought, "Hmmm, maybe this info should be made public." Compiled the page and posted, and throughout the years have modified the info as needed, especially for accommodating the 1987-88 Turbo Coupes (NATO board really helped with that).

My theory is: letting a handful of bolts defeat me is NOT an option. Man made it, man can fix it. Simple as that.

I will back amooset up though...beer is the key. ;)