Cougar

Check the relay for the AC fan and see if the relay is bad or if something is turning the relay on.

There may be a problem with the coolant temperature sensor for the ECU. This is different than the one for the gauge. It may have two leads instead of one. The sensors can go bad and make the ECU think the engine is always running cold and the fuel will be too rich.

The code is for the sensor circuit, not the sensor. Check the wiring to the sensor for a faulty connection.

I recommend you get a test light probe to check for power. First make sure power is getting on both sides of the fusible links. If they are ok then check the power to the fuses by placing the probe tip in the little slots on top of the fuses.

The grounded jumper lead is used to replace any suspected bad ground point, which is the frame and body of the car usually. Subaru uses a switched ground to turn on lights usually. This means power is tied to the lights, sometimes via a relay, and the switch controlled by the driver makes contact to ground in order to turn on the lights. You would not want to tie a ground jumper to the fuse box area since that is the HOT side of the circuit and you would short out whatever you tied to. If there is a bad ground somewhere then by placing the ground jumper in the car body area that has the bad ground will usually correct the trouble and you then know were to look for the trouble. If your brakes lights are working ok then the grounding in the rear area is probably ok. Unforunately I do not have access to my service data right now to look over the taillight circuit and won't have them until Wednesday. The problem problem my be with the illumination module as Nipper suggested. If you haven't checked the fuses under the hood then check those for a bad fuse.

Very good on your method of finding the problem. The vibration test can find a lot of trouble areas.

There may be a grounding problem causing this trouble. To see if that is so you could make a ground jumper and tie one end to the negative side of the battery. Then place the other end of the jumper on suspected bad ground points. If the trouble clears you know the area to look for a bad ground. The trouble may be in the dash area.

Daeron, you may be looking for miniature incadescent lamps. Check out this link and do a search for T-1 and T-3/4 lamps. http://www.shokaifareast.com/images/Lamps/Incandescent/T%20Type/t1b.PDF

To Legacy92_wagon: The problem may be due to a bad connection in the connector under the dash. My info shows power should be on a red wire going to a 21 pin connector under the dash left of the steering column. If power is okay there then the switch may be the trouble. To Coroboto: Check the connector under the on the passenger side near the wheel wheel. There is a connector that has two rows of 4 pins each. A red/blue wire supplies power to the rear lights. Note: This info is from my '88 manual. Hopefully it is the same for your model years.

I thought that MPFI didn't come out until '88 but I could be mistaken. The problem does seem to be with the injector(s) and need to be checked, as was mentioned.

MilesFox may be on to something there about the timing marks. I would hold off pulling the disty since it wasn't pulled out. I think the disty is turned by the driver side cam so that should be ok if that is so. You could do a compression check to see what that shows you, especially the passenger side.

I think the part you are talking about is in the rear taillight area, on the driver side.

For the taillight problem check fuses 7 and 12 in the main panel under the hood to see if they are ok. If they are good then check the relay for them in the same panel. I suspect that the running lights are lighting up with the brake lights because there is a broken filament in one of the brake lights. A filament for the running lights is touching the brake light filament. Try replacing the lights in the rear to see if that corrects that trouble.

Welcome to the forum. Hope you like it. We have some good helpful folks that use this site. Check the brake switch near the pedal and see if you have voltage at that point. There should be voltage on one side of the switch while the pedal is not being stepped on. I think there will be voltage on both sides of the contacts when the pedal is pressed down. You could also try jumpering the switch with a clip lead to see if that makes the lights work. Don't confuse the brake switch with the cruise control switch if you have one.

The only thing I think you will need then is the thermostat switch. Hopefully the radiator has a spot for installing one. Then just add your relay and power supply circuit to it. You don't have to have an electronic control to turn it on.

From what you stated in your first post it seems to me that all you need to do is add a bypass circuit to the fans. This would just take a fuse, relay, and switch to turn on the fans manually. I may not fully understand what you are trying to do though.

I would recommend you just replace the alternator instead of fixing it. The time and money it takes to rebuild one as good as a remanufactured unit isn't worth it to me, plus if something goes wrong you have a warranty to fall back on with the rebuild. I recommend you replace the alternator ASAP since 17 volts isn't a good thing to have going on the 12 volt system, especially for the headlights.

The warning lights are in the alternator circuit. You may be able to a place like Autozone test the regulator to see how it is. If the wiring looks ok I would guess the regulator is bad. You're welcome for the help.

It sounds like the regulator may be the trouble. I think it is seperate from the alternator. Make sure the wire connections are good between the the units also.

By using your voltmeter you should be able to figure out what is what. The ground connections will be at zero volts with reference to ground. The power line will be about 12 volts. The signal line may vary between 2 to 5 volts but I'm not exactly sure on that one. I think that is a close estimate anyways.

If the O2 sensor has less than 40k miles on it then I would tend to say it is probably ok. It might be best to take the car in to a shop that can do an exhaust gas analysis and see what it shows. The MAF sensor may be causing this but I would want to be sure of that before replacing it due to the cost of a new one. This problem seems strange since you state it runs well. I would think that with gas mileage as poor as you state the engine would not be running smoothly. The problem looks more like there is a gas leak somewhere than a engine problem.

I would say if the plugs look good then replacing them and the wires aren't going to help much. Replacing the O2 sensor may be the next best step and then the MAF sensor if that doesn't help.

To check the sensor resistance you can place it in a shallow pan of near boiling water. You know that it will be close to 212 deg F. Then check the resistance of the sensor when it has heated up to the water temperature. Compare what the reading is to the chart and see if it is close. I would guess that it should be within about 5 to 10 ohms of the chart if it is ok. Can you tell me what the chart says the resistance should be when the temperature is around 195 degress?

Hopefully we can come up with a correct solution to the problem. The kicker here is the problem happened right after the other carb was installed.

The sensor for the ECU usually has two wires going to it, instead of one that is for the gauge. It may be located behind the throttle body on the passenger side of the engine.