1991 GMC K1500 - Page 3 - Answered Questions & Fixed issues

try replacing the glow plug switch on the backside of the engine behind throttle body, my truck did the same thing. part costs about 40.00 at the dealer.

Go to your local auto parts store and look for a book, Haynes Diesel Engine Repair Manual, Part number 10330. It has your wiring diagram and a lot more. I got mine at Canadian Tire.

Check your cruise control fuse or relay. It will be in your owners manual. If fuse is good than the cruise itself may be faulty. Check continuity on cruise controler itself. If there is power, than the controller itself is bad and need to be replaced. If there is no power than it may be a faulty switch.

adjust brake switch on drake pedal for cruise .

is ther fire cming out of the coil if u got an old plug hook it to the coil wire and use it to check for spark if not try a control module if that dosent work im not sure i had an early 90s ford that did similar stuff and i put a crank sensor in it and it fired up not sure if chevys have those hope this helped n good luck

Sounds like the fan motor is hitting on somthing.

Take some chalk and coat the outside of the fan blade. Install it back into the truck and turn it on for a second. Take it out and see where the chalk like is inside the fan housing. make adjustments to anything it is hitting and/or replace fan if it is bent/damaged.

Your throttle valve on the transmisson is probley not adjusted to spec on this vehicle it runs from carb to right side of trans.


hope this helps

U may have a dirty valve body passage, have u changed the trans fluid and filter in the last 60,000 miles,. if no do and use the new GM Dexron VI trans fluid, it has greatly improved shift characteristic's and has the best detergent property out there to keep the trans clean. I have personnel experience with this fluid in my 96, I was amazed.

fuel pump

Make sure you have number one cylinder at top dead center, do this by removing the spark plug and puttin a screw driver in it, when it gets to the top stop, you turn the motor by using a socket on the crank shaft, if you do not get the cylinder to top dead center this will cause the problem, how ever this means you have to remove the chain again and realign every thing.

go to autozone.com

click on repair guide, then on specs, it tells you the gap in the specs.

No. Same Computer, different programming.

-JC

everything will bolt up the same the only difference between the two is the bore the 350 is the better engine of the two

sounds like a worn out distributor. fairly common on this type of vehicle good luck

I would look for harness damage under the bed since the brake and tails are seperate circuits.

Someone please call me 3365179318 I have a 1992 gmc topkick 366 engine and I noticed when I turn the key the fuel pump is not coming on. So I’m trying to find the fuse or relay for it to see if it’s maybe bad because the fuel pump ain’t even a year old. Someone please help me lol

top of intake must be removed and fuel pressure regulator is on fuel injection spiderremove small clip and pull out regulator then o ring and then fuel screen replacement is oppsite of removal

replace master cylinder

i replace alot of these at work some times as many as 10 a week.can you tell me your problem. if inside handle dont work remove door panel then you have to drill out rivet in handle then slide foward then disconect lock rod and door latch rod .your ready to replace handle if that your problem.if not you can let me know with a response.also you will need a rivit and a rivet gun to replace the rivet your going to drill out.any questions let me know

There should be a digital ratio adapter controller (DRAC) between the speed sensor and the instrument cluster (IP) that may be faulty (or the IP itself is faulty). Try replacing the DRAC (should be installed on the ECM bracket under the dash). Be sure to disconnect the battery before doing this.