"slow down" light

It's PROBABLY malfunctioning which seems almost "normal" at this age. BUT it might be correctly showing an overheated Cat. You need to figure out which it is. One solution, if legal in your area, is to remove the cat and install a straight pipe. Then there is nothing to overheat/cause a fire. I did that on my 328, not because I wanted to get rid of the cat but because the slow down light was false alarming so basically I had a non-working warning system.

The control units are not available so there is no way to repair the system if it fails. You can cheek/clean all the electrical connections and with luck, that might fix the problem but the odds are pretty good that the control unit has failed.

 

I've had those lights go on on my '83 308.
Don't ignore them.
They are telling you the cat(s) are overheating. Note the side of the light.
It's also suggesting one bank is cutting out on you

Look at the easy stuff first -
Oil leaking from the cam seals into the distributor cap causing a short/misfire
All spark plug cables tight & secure at the plugs and then at the caps and coil.
is the coil OK?
How's the rotor?
Then also check the ECUs in the back boot & make sure they are connected, dry, and the ground is good.

 

I had the brake failure light go on once...scared me at first, but it was pretty obvious I still had brakes.

I'm wondering if the pads are getting low or something like that...not sure.

 

The front pads have a wear detector that turns the light on when the pads get thin and creates a ground connection through the hub.

When I rebuilt my suspension I found the wires for this system broken internally to the wire at the pad connector where the wire was flexing as the suspension moved. I disconnected it and coiled up the wiring and and tied it up out of the way of the front steering box and arms. I check my brakes often enough that I don't need a low pad/wear indicator and it wasn't working anyway.

Your front pads might be low... and the wire intermittently connecting. its worth a look at your pad thicknesses on the fronts.

 

I have had my car for a little over a year and I had the slow down light come on once.. completely my fault. I had *almost* reinstalled the plug wires correctly.

Lester

 

Agree with the above - it could be nothing, or it could be dangerous.

When I got mine, I didn't notice (or didn't know to look, is more like it) that the slow down light didn't come on for a few seconds like it is supposed to when you get in and start up.

"Someone" (we don't know who, so I won't make any accusations) had disconnected the thermocouple, and gone to the trouble of snipping the wires and pulling them through so that you couldn't tell without a close inspection. One could speculate that this was done to stop the light from going on all the time and complicating the sale... but that's just speculation.

I drove it for a while thinking it was running a little lumpy. When I brought it in to my mechanic, he showed me the problem, showed me that it must have been done deliberately, showed me the totally destroyed Cat, and marveled that the car hadn't gone up in a ball of flames on the way to his shop.

So, it may be just a simple loose or corroded connection. But in any case, be on the safe side and don't ignore it.

 

Don't ignore it. I had the same issue in the first week I owned my 328. Turned out to be the HT leads but it could have been worse. You'll regret it if your pride and joy goes up in flames.

 

I'm thinking that's it - I will check.

 

Sorry to hi-jack the OP's slowdown light question.
This should be in a separate thread.
Do a search for Brake light.
I don't believe 308s had the brake pad sensors. 328s I'm not sure.
check your brake fluid level. It's also not uncommon the fluid float gets stuck, esp if you inverted the cap while you last filled it.
Check the electrical connections at the brake balance junction on the firewall. water had gotten into mine.

 

+1 on not ignoring the Slow Down light.

When I replaced the fuel injectors on my QV, the Slow Down light would also occasionally come on. I failed smog miserably. Took it to my trusty mechanic and the mixture was too rich, the cats were overheating. 10 minutes of his time to readjust the mixture.

You may want to look for a mechanic in your area to check the fuel mixture. There are several threads about this adjustment. It is in the mechanical fuel distributor, a plug needs to be removed to access the Allen adjustment bolt.

 

My 1987 328 began doing that (slow down light coming on) several years ago. I drove it down the interstate a high revs then quickly ducked into a rest stop with an infrared thermometer in hand. The exterior of the cat was about 700 F, not too hot in my opinion as I have seen them glow on other cars which means 1200 F. So I ignored the light for many months and went on my merry way.

One day I decided to crudely check the oxygen sensor by removing it and and attaching it to a multimeter while using a propane torch to heat the business end. Mine was very sluggish and did not put out much voltage. I no longer recall what the voltage should be but knew then and it was insufficient, and as mentioned, sluggish in changing. What prompted me to do this was the sudden drop off in fuel mileage on another vehicle of mine. I tested its oxygen sensor and found it sluggish and putting out low voltages. Replacing it fixed the fuel mileage problem. That car has no slow down light.

So I replaced the sensor in the 328. After about 1/2 hour of driving the slow down light quite coming on and has not come on since other than the test phase when you first start the car. Your results may vary. Good luck.

 

My cats have been removed. I'm thinking about using the slow down lights for turn signal indicators. Maybe then I won't forget to turn them off.

 

Good one!