OH MAN- What everyone fears from accident damage! A Short. And issues.

Got a short it seems. Dangit. Battery in the Roady would not keep a charge, despite me keeping it on a trickle charger, I kept having to jump the car to start it. Once started, it's fire right back up if shut off, but if left overnight the battery was flat.

Took the battery out, and it's 6-years old, and took a good hit when the deer got me, so Wally World tested it and said it had a bad cell. I bought a new battery, put it in yesterday, car fired right up. All seemed fine, gauges read fine...ok.

Decided to take a short drive to get the trans hot so I could re-check the level. Drove about a mile and all the sudden the radio and the climate control head went dark, then came back on (clock re-set when radio lost power), then both went dark again, then came back on, and even weirder when the radio came on the AUTO TONE changed from Pop to Rock to C/W all on it's own! SAY WHAT????

I shut the radio off and drove home. The car itself ran fine. Headlights didn't dim, volt gauge never jumped, no other issues.

SO I know this is about impossible to diagnose, especially online, but any ideas are appreciated. I am going to re-check the battery connections (they're clean, I know that) and the grounds for the wiring on the radiator support. I unplugged no wiring when doing the accident repairs, but all the harnesses on the front got moved and re-fed. And there are grounds on both sides of the radiator into the support. I'm going to unscrew those and sand some of the fresh paint off under them so hopefully that will create a better ground.

Couple of other things to add to the fun. I still had not seen the new engine fans come on, but had not let the car get really HOT yet, and since the a/c is not charged could not turn on the compressor to kick the fans on that way, so I read online to unplug the sensor at the water pump and that would kick the fans on. I did that and after a few seconds the passenger side fan came on, and then the driver's side followed. Good, they both work, but when I went to shut the car off, before re-plugging in the sensor, the Check Engine light was on. HA! I'm wondering, being a '96 OBDII car, if unplugging that sensor tripped the light. I HOPE that was it and that it's not related to the issue above.

LASTLY I think I overfilled the cooling system. The car did not come close to overheating, gauge never got above the halfway point, but I have coolant seeping out of the overflow bottle...looks like it's coming from around the cap on the bottle. Cap is new, and on tightly, but coolant seeps from around it onto the bottle and then drips down onto the (freshly-painted) front frame rail. I HOPE I just overfilled it. Is that how these are designed, if overfull to seep out like that?

Looks like I have some tinkering to do this weekend,

-Mike

I think it's likely that your CEL will go off when you reconnect your temp sensor.

When you filled the cooling system, did you bleed the trapped air, using the bleeder on the back of the thermostat housing?

paart wrote:

I think it's likely that your CEL will go off when you reconnect your temp sensor.

When you filled the cooling system, did you bleed the trapped air, using the bleeder on the back of the thermostat housing?

No I didn't open the bleeder. Just filled the cooling system and ran it with the cap off until the thermostat opened, and topped off from there and capped it off. I've run it quite a few times since then. Heater will fire pottery under the dash so I know it's not low. It's well above the COLD line on the bottle now though, so think I overfilled it.

Thanks for the reply. And yes I'm hoping the CEL goes back out now that the sensor is plugged back in.

The "reverse cooled" LT-1 traps air in the system when refilled, whether the thermostat is open or closed. That's why the bleeder was installed. The "bottle" is an integral part of the cooling system, not an overflow catch bottle, like most cars. The bottle will eventually remove all the air from the cooling system, although it may take a number of cycles or days to do so. At that time, you will find that the coolant level is low. Keep your eye on it.

paart wrote:

The "reverse cooled" LT-1 traps air in the system when refilled, whether the thermostat is open or closed. That's why the bleeder was installed. The "bottle" is an integral part of the cooling system, not an overflow catch bottle, like most cars. The bottle will eventually remove all the air from the cooling system, although it may take a number of cycles or days to do so. At that time, you will find that the coolant level is low. Keep your eye on it.

Thanks and will do!

-Mike

CEL's often dont go off immediately when the fault is corrected. Really need a code reader to be sure and to turn the CEL off if it's just not clearing the code itself.

MG Davis wrote:

CEL's often dont go off immediately when the fault is corrected.  Really need a code reader to be sure and to turn the CEL off if it's just not clearing the code itself.

I'm going to go all through everything electrical that I touched this weekend, then will drive the car again and cross me fingers. We shall see!

The CEL will go out immediately once reconnected if all you did was disconnect the sensor. It's a common test. I have done it many times to test them.

My 96 and 95 set a check engine light as soon as you disconnect the temperature sensor. The PCM will then start the fans. Takes a few seconds as you described. The check engine light goes out when it's re-connected. I have done this before long trips just to make sure they were working.

Car may or may not start with it disconnected. The PCM thinks it's about -40 degrees and puts a whole bunch of fuel in. The one time I tried it I could smell fuel and the car did not start. It was way too rich.

YMMV
-D

YachtDriver wrote:

Car may or may not start with it disconnected. The PCM thinks it's about -40 degrees and puts a whole bunch of fuel in. The one time I tried it I could smell fuel and the car did not start. It was way too rich.

YMMV
-D

Well that makes sense too! When I did go to start it, it cranked longer than normal before catching, exactly like if it was flooded. Once it caught it ran fine, but all I did was pull it back in the garage.

SO it seems the Check Engine light and Coolant overfill issues are simple. Just need to track down what caused the Climate Control and Radio to flicker while driving last night. Such fun.

Thanks All!

-Mike

I have no advice, but I too am suffering from phantom electrical problems following sombody doing a hit and run in the parking. My flashers just stopped working. No clicking, nothing. Sometimes I get one solid arrow (always right).

I feel your pain.

mike check the connection at the auxilliary post,.

Jason,. put a new flasher in it,.

The cooling system in these cars is easier to purge of air if you let it pressurize. If you run it with the cap off the air seems to never get pushed out. Let it reach temperature from cold with the cap on and then cool down. Refill as necessary and repeat. Also make use of the bleeder screw as noted here.

If you have a cooling system pressure tester, you can do pressure cycling with that. I did that the last time I had to drain and refill, and that made the process go faster for me. Burped out a lot of the air before I fired it up.

This is interresting, where exactly did you guys get damage on your cars?

I found the ground next to the battery that bolts too the fender was loose.  I thought that was it, but the radio was still acting up, so I replaced it.  

https://gmlongroof.4umer.com/t12679-i-think-the-delco-in-my-96-roady-is-dying

All good now!

-Mike