Top 20 1989 GMC K1500 Questions & Answers

have the fault codes read first using a scan tool with GM protocol installed ( not all scanners are capable of reading GM codes there will be a code recorded doubt if it will be a pump problem but it could be a pressure regulator problem or an EVAP system problem

crawl under truck and on front diff unhook actuator put fuse in if your fuse doesn't blow id say actuator is bad my plow truck did same thing and I think my blower motor stopped too

Spark plugs are set at 0.035 inch. Ignition timing is set at 0 degrees BTDC. The computer then controls the timing from there. There will be a wire that you unplug before you set the timing, then once you have verified that the timing is at 0 degrees, then reconnect the wire and you're done.

get a haynes repair manuel, worth every penny, just do it

check to make sure you have no vacuum leaks. u can use a cheap can of carburator cleaner and spray around the vacuum lines of the truck, if your truck starts idling up and changing, you have a leak then just replace the line. Older GM vehicles rely on Vacuum advances for the transmission and will not shift properly nor downshift if there is a leak. a lot of vehicles rely on vacuum to support many functions, mainly driveability as well as smooth running. there should be a vacuum line that runs near the rear of the transmission. also might want to check transmission fluid for the no power, cause even though you may have power in 1st and 2nd, 3rd gear is your main drive gear unless you have a 700R4 with automatic overdrive and it could be suffering from not enough fluid getting to the bands from the pump. also one more thing, check the downshift linkage cable the runs from the carburator to the transmission, make sure it is working, sometimes you can have a broken cable in the line and not even know it. hope this helps

Try this --- https://www.youtube.com/watch?v=LM4YNSlgVDc

i assume you mean the starter solenoid its on the starter on the passenger side under exaust manifold

what have you checked so far ? will it start using starting fluid sprayed into the intake ?

Very common of the GM's, I've changed out many climate controls! You should be able to pick 1 up at most any salvage yard for a very reasonable price and it never hurts to check with the parts stores as well as they have started carrying them too! Hope this helps you.

Should be fairly easy. You disconnect the battery, release tension on the belt, and remove the alternator.

Sounds like your pump is having problems pumping fluid due to a plugged up transmission filter. Or it might be going bad.

I had a same problem on a Chevy. and it turned out to be vacuum I had to rebuilt the heads. As I drove it would run rough, as soon as I would check it out I would not find any vacuum.

You might have somebody press the pedal as you get down and check the clutch travel. Might have an adjustment on the clutch arm. Could have wrong pressure plate, did you match them. I would check the travel first.

Check to see if you have power going to the switch with a test light. Also do the turn signal lights light up on the dash as you lift the arm up or push it down. If so you have a bad flasher which will located under the dash towards the firewall.

Timing. Your probably not TDC.

fuel pump , fuel pump relay on fire wall, fuel filter, may all need replaced, pump in tank, inspect all wiring in this circuit, especially all grounds,, grounds get overlooked & that is sometimes the problem. I have a 1988 gmc 2500, I 'm talking from experience. can you hear if fuel pump runs for 2 seconds, when you turn key on ? if not, ground problem or pump problem. relay has a fuse in it, check that. check all fuses. NOW, spark ! coil ? plug wires ? distributor cap & rotor ? replace them if you haven't !!!!!!!!!! get to work, see how you do ! good luck !

See if this helps you out --- https://www.youtube.com/watch?v=LM4YNSlgVDc

If you take off the inside Door Panel. You should see a Belt that goes through the gears, check and see if it is broke. You probably need to replace it.

It should be on the right side of the column under the gear selector right behind the steering wheel. Its a little knob.

You could have weak engine control module or a pick-up coil. Have your module tested first.