The dash project keeps rolling along. Originally I was just going to use the Fiero HVAC controls mounted in the Toyota dash, but after a couple tries, I just didn't like the way they looked so I decided to scrap that idea and use the Toyota push button HVAC control. The problem with that plan was that Toyota designed their system to operate by switching the ground side of the circuit whereas the Fiero works by switching the positive side. This means I needed to make some sort of interface to go between Toyota and Fiero. The blower motor side of things was a somewhat easy solution, I just installed a GM blower switch. The hard part was finding one with 4 speeds and an "OFF" position that fit properly. After a couple hours wandering around the pick-n-pull, I found this one:



It's from a 1997 Chevy Monte Carlo and fits nicely in the Toyota HVAC with only slight modifications.



The mode door switches were a different story...... Since the internal circuitry was set up for ground side switching, I needed to build a relay module to make it work. The way it works is that when a button is pushed on the Toyota HVAC control it turns the appropriate relay on or off, the relay then switches power to the mode and recirc doors.

To get started, I purchased a bunch of 15amp micro relays from DigiKey, these will stand in for the old Fiero push buttons. Next I needed to make a PC board to mount them to and keep the wiring simple and organized. I also designed the board to use the factory connector which saved me a lot of soldering time. First I laid out and drilled the holes for the relays and then used a Sharpie marker to draw in the circuit paths. After a short dip in the etching solution, this is the result:



I then soldered on the relays and attached the Toyota wiring connector. I also transferred the two PTC thermistors from the Fiero board to my board to try and keep things like OEM.





I needed to switch a few wires around in the factory connector to line up with the way I laid out circuits on my board. I plugged it in, turned on the power, and crossed my fingers..... much to my relief, everything works perfectly! All the modes switch as they should and the recirc door opens and closes. I still need to buy a plastic project box from Radio Shack to mount my board in to protect it but this part of the project is done.

[This message has been edited by seajai (edited 10-02-2023).]

So with the heater controls figured out, it was on to the air delivery. The windshield defrost and floor vents weren't an issue because they're part of the car half of the air box, the side window defrosters and dash vents required a little bit of work. First off i removed the ductwork from the dash and cut out the center section, I then shortened it and boxed in the ends and added round ports for flexible ducting.



For the dash vents, I cut off the Toyota pieces, plastic welded on a couple bottoms and installed round ports.



Once the dash was installed for the last time, I hooked up the vents with flex hose. For the side window defrosters I used 1-1/4" vacuum cleaner hose. For the dash vents I used 2" vent hose made by Dorman. It was some very nice stuff and worked quite well. http://www.dormanproducts.com/p-20898-96002.aspx

I had to cut 4" of depth out of the glove box insert to get it to fit. I sectioned the back piece and plastic welded it back together. I used the waste to cut pieces to fill the gaps left by sectioning.



This was a lot of work to go through just to get a glove box but I am really happy with the results. I still need to work on the center console and build door panels but for now I think I will just drive and enjoy it. Here are 3 pics of the finished product:

[This message has been edited by seajai (edited 10-02-2023).]

2 weeks to the Dells and my engine has started hemorrhaging oil. Lifted it up and let it idle with the inspection cover removed, looks like its the rear main seal leaking. I designed the rear cross member to be removed independent of the cradle so I can pull the transmission without removing the engine or cradle......looks like I get to test my design.

[This message has been edited by seajai (edited 10-02-2023).]

My design worked well, only took a couple hours to remove the transmission. With my high lift jack and a set of tall jackstands I was able to get my car up nice and high, which makes working on it pretty easy.



Spent $50 on a transmission adapter for my floor jack. I'd have to say it was the best$50 bucks I've ever spent.



Plenty of room to work now. I replaced the camshaft thrust plate gaskets as well since both were also leaking.



Got it all put back together and let it run for a little bit and didn't see any leaks, hopefully the seal takes care of it because the oil pan gasket will be a big PITA if it needs to be replaced.

[This message has been edited by seajai (edited 10-02-2023).]

[This message has been edited by infinitewill (edited 01-05-2016).]

Had an inner C/V boot tear open on the highway yesterday, sprayed grease all over everything including my right side catalytic converter. I had to pull over because I thought the car was burning. At least it was a cheap fix, $17 for a boot and an hour to swap it out.

Also got my Fiero Fiberglass sail windows wrapped in 3M carbon fiber vinyl and installed on the car:

[This message has been edited by seajai (edited 10-02-2023).]