Hello everyone.
Well, my '91 Z28 has been falling apart little piece by piece. It still runs okay, but little problems have been adding up. Rather than creating a thread for each, I am just going to go hog-wild and unload them here. If you have ideas, or suggestions, please don't hesitate to chime in! Here's what's up:

1. Driver's window- This is probably the strangest problem. I can roll up or down (easier down), but only for a second or two at a time. If I give it a rest for a couple minutes, I can roll in either direction again for a few seconds. Here's my best theory so far: The motor is old and drawing too many amps causing a thermal breaker somewhere to heat up quickly. Once it cools back down, I can move a little more....? Maybe? Ideas?

2. Starter freespin- My starter rarely catches the first time and will instead freespin until I try enough times for it to catch and start up. Usually takes 3x or so to start. Might be my imagination, but seems more of a problem when its cold or has been sitting.

3. Cooling fan- I have a single electric cooling fan that won't turn on. I have replaced the Coolant Fan Sensor already and just recently located and checked out the relay. No problem with either. The fan works fine when bypassed, and currently I have a manual switch to the dash to trigger the relay thereby activating the fan. I'd like to not require a workaround- does this mean there is a broken wire between relay and CFS?

4. Brights- The brights don't flip on using the signal lever unless I tilt the wheel (and hold it) all the way down, then use the lever. Sometimes trying to turn them on turns all headlights out completely.

5. Chime- In an effort to drive me completely insane, the chime sound now remains on while my dash lights are on. I can turn it off by adjusting the lights **** so that there are no dash lights, and in this adjustment, dim to bright and reverse happens suddenly, rather than the gradiated dimming you'd expect. I pulled out the chime and all is well and quiet now, but what's up with that?


There are a handfull of other minor issues, but those are the most serious and mysterious. Any ideas from anyone would be much appreciated! Thanks in advance!
-Kevin

 

Here's my observations:

1:Windows- I think you are right to suspect the motors. I dunno if there's any thermal breakers in the system, but i'd take a good hard look at the motor.

2:Starter- Two options. Your starter is loose or somehow out of alignment, and the pinion won't allign with the flywheel teeth. it should be possible to adjust the mounting of the motor for better engagement.
Alternatively, the mechanism in the motor itself that moves the pinion in to engagement with the flywheel is worn out /broken. This requires replacement of the whole starter motor.

3: Cooling Fan- It sounds like a short to me, too. if you can, try to bypass that run of wire to see if you can get the relay to come on.

4:High-Beams- Sounds like a mechanical or a contact problem in the hi-beam switch itself. This will require getting inside the steering column and patiently observing the operation of the switch. I think something has come loose, and the lever doesn't make a good contact on the switch.

5:Chime- Your dash lights are switched by a relay attatched to the parking light circuit. The chime is controled by a relay attatched to the instrument light circuit. There is an other relay that opens the chime circuit when the keys are in, so the buzzer doesn't sound.
Somewhere in the distribution block or the dash is a relay that tells the chime to come on when the keys are removed when the lights are on. When the keys are in, the relay is held open and the chime won't sound.
I'd suspect this relay, though I have no idea where it is.

Good luck debugging. Now that I think about it, there's a bunch of little stuff on my car i've been meaning to look at 'one of those days' Maybe if it ever stops raining.........

 

1 Replace the window motor

2 replace the starter



4 Adjust the lever going to the switch, its under the steering column and is a bear to get to.

 

K-D,

1. The window motor hads a thermal breaker right in the end of the motor hosing. The motor is likely drawing too much current because the window is misaligned, the weather is cold, adn the guides no longer have adequate lubrication. This can be aggrevated by worn brushes in the motor, but a new motor may not solve your problem. You'll need to open the door trim to access the motor and repair or replace the motor and clean/lube/adjust the window regulator mechanism. This might help: Power Window Motor Repair
   
2. The overrunning clutch (Bendix) on the starter is either worn and spinning freely, or is not being engaged by the solenoid linkage (again, from wear). In either case, the starter needs to be removed for repair or replacement. The mechanism is very simple and straightforward. Once you get the solenoid removed, you should be able to identify the problem readily.
   
3. The fan relay is controlled by the ECM. The ECM will not operate teh fan until the coolant temperature is at 223°F or higher, or if the AC compressor is on and the high side system pressure is above 175 PSI. If you can cause the fan to operate bt grounding the dark green/white wire from the relay, the fan and relay are O.K., and you need to investigate the wiring harness, ECM, and ECM grounds. You should also test the CTS for accurate resistance at a known temperature.
   
4. The high beam lamp switch is located on the top of the steering column, near the firewall (just next to and above the ignition switch). It is controlled via linkage rods from the multifunction lever. Your situation is not uncommon, and can usually be solved by adjusting the position of the switch.
   
5. Your Z may or may not have the transistor switching module for the dash lights (as Firebirds do). In the driver's footwell, there is a swingout Convenience Center that mounts the chime, some relays, flasher, etc. Just above and to the right of that (toward the radio pedestal) is the switching module. Your symptoms sound like you have a failed transistor, which can easily be replaced with a Radio Shack part. If your car does NOT have the transistor switchin module, lights are controlled purely by the potentiometer in the light switch, and it would need either cleaning or replacement.

 

I own a 1991 and have the same problem #4.

My brights used to work fine as I pulled the the lever in, and my brights would work no problem. Now, all of a sudden, when you pull the lever in like normal, it just doesn't work. Nor does it click like it sounds like its working. I am not sure what this is, but I feel if I pull any harder on the lever its gonna break. I am not sure how I can fix this, but its weird how it all of a sudden stopped working on me.

 

Kevin,

For your fan
did you run the toggle strait off the battery or did you put in a fuse? Im curious as to how you did that ?

 

brights-

MY 90 RS did the EXACT same thing - if it's like my 90 RS, there is a switch at the bottom of the steering column that needs replaced. there are rods that run from the lever, through the column, and control this switch mounted to the column. have someone flik the lever while u are under with flashlight, and check into that. the switch is also positionable, so it may just need moved and tightened back down.

fan -

my 90 RS has a fan switch located under pass side, on the head i think. ECM doesn't control fan on a 90 - if the 91 is same, maybe u need a new fan switch.

 

First of all-
Thanks to everyone who replied! The fact that this community exists due to one car is amazing in itself, but even more amazing is the fact that there are so many active and brilliant members willing to help! Its great to have people familiar with your car who know exactly what goes where. Thanks again!

In response to posts:
1. The driver's window- I suspected the motor! Thanks Vader for the info and the news of the thermal breaker on the end of the motor. Makes perfect sense now.

2. Starter- doesn't sound TOO bad to fix. I think I'll wait until its nice and warm to crawl under my car though.

3. Fan- the bypass is good for now. Someone asked how I did it: First I bypassed it (in a pinch) by running + directly from the battery. I didn't need it on very often so that was okay, but required popping the hood to turn on/off. Now, I have some small gauge wire running to the dash and triggering the just the relay coil which in turn turns on the fan as it should.

I'm surprised to hear the ECM is involved in the process, if the ECM has its own temp sensor giving it a value, then why would I need a coolant fan switch located (as mentioned) on the passenger's side head between exhaust ports 3&4? I don't get it.

4. Brights- yea, I assumed it was the switch, but was hoping not to have to pull the column apart and mess with it. Oh well.

5. Chime- will check this again one of these days, but now that I ripped out the chime module, its not nearly as bothersome. This may have something to do with my keyless entry/alarm that is wired to the parking lights to signal arm/disarm modes, though the system has been working for months with no problems. I don't know what would trigger this.

Anyway, it will be a while till I get around to fixing this stuff, but thanks again for the help!
-Kevin

 

As for the temp switch on the pass side head, it is for the second fan on cars that have 2 radiator fans. I know the TPI 350 engs had it; not sure abt the others.

The first fan (and maybe the only fan on your car) is controlled by the ECM like Vader was saying.