20 Most Recent 1988 Chevrolet G30 Questions & Answers

Engine control module

Have you put a spark plug fire tester on the plug wire and verified there is no fire at the plugs or do you just figure because it is getting gas if must be an issue with the fire. I ask this because the age of the truck it may have a plugged converter or muffler on the truck and if one of them are plugged it won't allow the engine to pull the fuel into the cylinders and fire. You can remove the 02 sensor ahead of the cat and the truck will start if one of them is plugged up. The truck will not run well but it will start and run ruff. Hope this helps.

defrost is the defalt mode look for a damaged vacuum line going ti the control head

The ignition module or HEI module commonly goes out on those. It's about a $30-50 part and is under the rotor button on the distributor. The reluctor wheel on the distributor could also not be reading correctly...only fix for that would be a new distributor which would probably come with an ignition module.

weak fuel pump

The canister for the vent for the fuel,and tank,needs to be replaced,and clean the carburetor out.

It sounds like the alternator is not properly lined up. You had the belt on right the first time. Put it back on and before you start the truck check the alignment on the belt. From the side of the truck look down thw belt to the fan pulley and see if you notice a slight bend, or use a straight edge to do the same thing. Also sight down the belt to the crank for the same thing. Yoiu may have to shim out the alternator brackets to get the belt in line with the other pulleys. Hope this helps.

No problem.... Some harnesses use an adapter harness, if you need one get it from the dealer or remove all wires from the new plug and put them into the old harness end. (draw a picture for reference so you don't mix them up) Hope yours matches up!!

My sincere apologies for the delayed response.
I am personally going back to answer your unanswered questions.

I do not know if you still need this information, but I am going ahead and answering it anyway. You may want to Print the Diagrams for future use.

CLICK on the following LINK. It has the Belt Diagrams you will need.
If you would: Before Clicking: Let me know if this helped you, or if you have any additional information or questions. Feel Free to contact me at FixYa.com!
Again my apologies...
http://www.2carpros.com/car_repair_information/year/1988/make/chevrolet/model/step_van/1988_chevrolet_step_van_drive_belt_routing_diagram.htm

You want at least 850 cold cranking amps for a diesel.

on the left and right sides up by the dash on the box there is a latch and on the bottom of the box at the floor there are 2 bolts that come out ,sometimes the cover sticks due to the gasket,after you undue the latches and bolts it should slide out.

Check the fuel system. Check the distributor cap and wires. Try turning it over and holding the accelerater down at the same time. if it fires up you should check your fuel filter or pump. that usually means your not getting enough gas.

go to a salvage yard they may have one on a car.

Tail light bulbs can blow fuses when they fail. Remove the bulbs and test them with a meter, or with a piece of wire to the battery terminals. Check the grounds and connectors that are near the rear lights. Check underneath for cut or broken wires. The dash lights are more of a puzzle. A corroded or loose connector is the most likely. Older vehicles do have small capless bulbs in the dash. ..

Go to gm.com/support. Likely you won't find it. Motor homes are a special breed and even an RV dealer would have trouble and end up doing it in house.

It's most likely a wheel speed sensor at fault. Check the connectors and wires behind each wheel. Sometimes corrosion builds up in the connectors or sometimes wires break...and sometimes the sensors just plain fail. Your brakes will work just fine but you've prolly lost ABS function. If you can lock up your brakes, ABS is disabled until the signal is restored.