20 Most Recent 1986 GMC K1500 - Page 6 Questions & Answers

I'm not sure exactly what your problem is. When you "click" your lights to low beam, your high beams should not work. But if your low beams work when you "click" them on, but your high beams don't work when you "click" them on, you either have a blown fuse, bad relay or high beam elements burned out on both lamps. (Not so unusual) Possibly a bad "dimmer" stalk switch or bad wiring, too, but a little less likely.

First thing to check is the cabin filter..The vehicle will tell you where the filter is ,,and how to change it..Also make sure there is no obstructions in the return..Usually under the glove box area or around the cowl which is outside underneath the wiper arm

Hi, Sounds like you may have a vacume leak and soap will just be sucked in to the motor.I would check for loose bolts on throttle body or rubber seals that are loose.Check for cracked rubber hoses also or loose hoses. Throttle body may have a split gasket as well.You can use a stethoscope that can be bought at auto parts to pin point noise or soft piece of paper. Thank Y for choosing FixYa.

you may check the amount of voltage by voltmeter at the blower motor connector with your ignation on ( car on idle) and AC running, you need to replace the motor if it reads 12V below. You may also try cleaning the air exhaust for that matter.

please explain in more detail. thanks.

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The 88 up to 2000 model of this truck utilizes 5 types of automatic transmissions with both 700r4 transmission and the 4L160E. They should bolt on together. Watch out for the lines that go with it including the ground connectors.

check the ecm fuses first. then check to see if a scan tool will communicate with the ECM. if not, then check to see if you have a sensor shorted out that is shutting off the 5 volt circuit of the ECM and not allowing to truck to start.

check the relays & fuses

if computer command truck with an ECM replace the engine's oil pressure sensor. It has 3 wires to it and one runs to the fuel pump to prime upon starting the engine. Once oil pressure is acheived the computer switches that senors wires circuit off and turns on the fuel pump relay to take over the fuel pumps operations till you shut the engine off

if fuel pump is working ? then your float or floats are stuck try softly tapping around carb with a rubber mallet while cranking. dont help floats could be bad, or float seat ****

may want to check the fuel pump relay. also the crossed out oil pressure switch is a safety feature to stall the engine if oil pressure drops. it is possible the oil sending unit is bad also.

Here how it looks like