1991 GMC K1500 - Page 4 - Answered Questions & Fixed issues

The fittings on the engine will come with the o-rings and plastic fastener Run to parts store and pick one up

overdrive servo/ solenoid is not operational , either from failed unit or wiring problem check transmission actuator for operation or adjustment as well

maybe your running hot, check your coolant to water ratio.

If the engine is trying to flood, it will kill the engine. If you have the spider fuel system, it is noted for problems. If it cranks good but won't start, have a helper crank it while you check for spark at the spark plugs. If spark everywhere, use a gage and check proper fuel pressure, also, check fuel injector pulse. I don't know if this may be a problem? below

maybe wiper arm mechanism on way out

Parts stores sell a Haynes trans manual for GM which should cover this.

Drive shaft carrier bearing.

Id guess shift linkages are messed up. or controls for the change to 4 by 4. Guess you got what you paid for? Drives in 2 wheel ok right? At least that part is good?

under hood fuse block If you need further help, I’m available over the phone at https://www.6ya.com/expert/mike_9693b5ad75773352

front hub may not be pushing gear into hub remove hub check spring and gear If you need further help, I’m available over the phone at https://www.6ya.com/expert/mike_9693b5ad75773352

Hope this helps.

What you can try doing is purchasing just a new connector that if you can still use the same actuator. They do sell them depending on the year of your truck. Or try a junk yard.

Try your dimmer switch, when they go bad we either have bright or dim.

I would make sure your fuel pump is fully operational and is pushing the recommended pressure of 35 psi. You will need a fuel pump pressure gauge (tester). I would start here and them move forward.

Need to check neutral safety switch on automatic trans.

When you cycle ignition to on position , you should hear fuel pump relay under hood buzz for a few seconds then it stops .

There's a routing diagram sticker under the hood. Look for it on the radiator support , the front shock tower or on the hood itself. type this on google and see what you get...gmc k1500 serpentine belt routing diagram

Fuel pressure reading will give you the answer.but O2 sensor,engine temp,trottle position sensor,poor combustion like cylinder compression spark plugs, valve timing As you can see there a lot of things that can change the rich and poor fuel metering. hope it helps

If you are talking about the brake pedal being stiff and too hard to push, then working easily again - it sounds like you temporarily lost the power assist. This will happen again and it is not safe to drive until properly repaired. Many decades ago cars had no power assist and took much more foot pressure and much longer distance to stop. So your brakes were working, just not the assist. The power assist is provided by a vacuum line from the engine. The likely causes of the failure are: stalling or stopped engine, leak in hose from engine to brake assist booster or leak in the diaphragm inside the brake booster. There are also other much less likely causes from brake fluid lines and the master cylinder. Regardless, don't drive knowing the brakes are likely to fail.

If It has fuel injection it can be the fuel pressure valve, that hold the fuel pressure on the reel with the injectors. you can check it bi clamping the fuel return line so it can not flow (to see if the fuel is just going around back to the tank with out making pressure), and se if it can run but it is just to check it out, the valve can be stuck after the fuel filter was full and pass some dirt thru the system. but i don't know this type of car, just passing some ideas