20 Most Recent 1993 GMC Sierra K1500 Questions & Answers

fuel pump died replaced it truck ran poorly afterwards. Had a prussuer test done pump determend pump was no good. Put in another ran good for 2 days started running poorly hard to start no power. 2nd fuel pump. So i figure another bad new fuel pump wow changed it put in a third brand new fuel pump. Still will not eve start now. I had it tuned up 2 months ago new plugs rotor, cap, etc. put in a new fuel filter made sure it is on proper checked all connections for leaks. this cannot be a fuel pump problem now. no problem with the elctrical i figure i have great spark on ignition tester. I can hear the fuel pump prime when i turn the key. but when i went and checked the fuel port i had no pressure. When it is being cranked gas sews out of the test port. Also i dont if this is comon cause i used to turn my keyand go. but when i have someone turn the key and i listen at the gas tank whn the key is shut off i hear gs spraying back into the gas tank. So i am open for opinions.

first u must put the engine to the top dead center by lining up the marks on the front pully of the crankshaft also make sure the marks are on the intake stroke and not the exhaust stroke by taking out the number one spark plug and putting a small piece of rag in the hole . not all the way in leave some hanging out. now rotate the crank by 5/8 socket and breaker bar clockwise until you hear a pop as the number one piston blows out the rag from the plug hole signaling that the piston is on the intake stroke .check marks on the pully for exact timing .next get the distributor and drop in the hole making sure to point the rotor to the direction of the number one piston also making sure to seat the distributor all the way down leaving the keeper loose to align rotor to the number one spark plug wire on the cap . install wires to spark plugs .next have someone crank the engine while you are turning the distributor slightly til you hear the motor start this might take a few times to get correctand a timing light will be needed for final adjustment.

first check bulbs under the bumper twist and pull out the wires leading to the light if bulb is kinda silver and black inside the bulb is blown if the parking lights work its most likly the bulb

check fuel pressure and if good clean mass air flow sensor also check spark plug gap

check shift linkage

Check at injector wire with a test anoid light blinking while cranking engine if there is a signal to the injectors. The + signal is from a FUSE. and the - signal is from the ECM. If it's an ECM problem, before changing it. Check all positive and ground at ECM pinout check. Hope it helps.

You have to remove the two tubes and change 2 o'ring or seal. Warning; before removing the bolt you need to release R-134a pressure. Refill with 1onces of A/C oil compressor and fill with the specifications of R-134a. Hope it helps.

Need to change valves steam seal. There is a leak of engine oil during cool down of the engine. So when you start the cold engine it is burning oil that leak inside the combustion chamber. Hope it helps.

your fuse panel is either under the dash by the drivers left knee or on the side of the dash where it meets the door. the radio fuse should be the second from the top right side of the fuse panel. its a 10 amp fuse. the power for the switch should be a 16 gauge wire run from the passenger firewall (under hood.) behind a plastic cover where a lot of wires are bolted to posts. that red wire feeds power to almost everything in the cab. it runs behind the glove box and has a disconnect there. if the fuse is not bad and the wire looks good, check the ground on the passenger door "open switch" (the one that is supposed to turn on the dome light. that is where the whole system is grounded for the int. lights lights

Does it shift rough due to the idle speed of the engine? If I had to make a guess, it sound like the distributor cap has water in it or has melted a bit. Check into that. Could be a bad spark plug or wire too.

Does it miss at idle or going down the road, maybe both? Any applicable trouble codes? If you have that spider fuel system, I usually suspect that first. That system is noted for problems. You could try a cylinder balance test, engine idling, you could kill the cylinders one at a time, quickly. If you kill a cylinder that has no effect on the idle, the cylinder is dead. Then you have to decide if problem is spark--fuel--compression on that cylinder.

I'm assuming "white" smoke and not "black" since you didn't mention. If white smoke, it's coolant or oil leaking into the cylinder heads while it is not running. If oil and from leaking valve guide seals, it's not a serious thing and basically a nuisance. Just keep your motor oil level topped off until you have new seals installed or dispose of vehicle. If coolant, it's a much more serious problem. The liquid in the head will do two things. One, foul the spark plug and possibly cause hydraulic lock (fluids cannot be compressed and cylinder locks up) Check you oil level and if keeps going down a quart every few hundred miles, it's the valve seals. Check your coolant. If down, it's possibly a head gasket leak, which is not uncommon for vintage and make. If coolant keeps going down and not leaking on ground, that's a smoking gun, not to make a bad pun, for a leaking head gasket. At this point, it's prudent to first invest $10 on Barr's Leak Copper (looks like liquid copper in a jar) and add to your coolant system. Follow manufacturer's instructions and then see if problem either persists or abates. If it abates, go and buy a lottery ticket since you're very lucky and solved a serious problem with an inexpensive fix. Good Luck

The fuel level gage sending unit is defective, very common problem. The sending unit comes with a new fuel pump and is referred to as a module, also make darn sure you replace the fuel pump connector at the fuel tank, solder and shrink tube the new connector on, DO NOT USE CRIMP CONNECTORS.

it indicates injector problems leaking injector seal /s dirty injectors you can try moving no 4 injector to another cylinder and if the misfire moves as well , replace that injector it it doesn't move the misfire , it is coils or ECM problems

I need to know , do you frequently run the fuel level to below 1/8 of a tank?
Has it been giving you any signs?
We need to know if there is fuel presure
Is there Spark at all 8
has it been in heavy driving through puddles

That is not a radio. That is a control head. The 7 wires carry data to the radio brain which on this trucks is a silver box located directly above the gas pedal. These trucks also had an optional cassette player/ cassette and eq unit that was mounted in the center of the dash that also connected to the radio brain as well.

I have 1993 gmc 4.3 vortec v6 turns over but want start. replaced fuel pump, fuel pump regulator ,ecm, tps, coil

Sounds as if the clutch is no good or is engaged constantly. Possible clutch worn out or throwout bearing is seized on input shaft

I'm going way back into my alcohol erased memory on this one, but check your oil level sender. I ran into this problem many years ago and it seems like that was the culprit.