Why does my C3500’s check engine light come on when I start it?

It's okay if your check engine light comes on when you first start your vehicle. This is just your C3500 testing its circuits. The light should go off shortly. Bring your vehicle in if it doesn't.

Are GMC C3500 engine noises bad?

Unusual noises can signal a problem with your GMC C3500 engine. Tapping or knocking could mean you need an oil change. A high-pitched whistle could signal an intake leak or misaligned belt. Squealing may be caused by a loose fan belt, and grinding might be coming from the brakes, not the engine.

What could damage my GMC C3500 engine?

Certain driving habits can hurt your engine. These habits include driving on an empty fuel tank, revving your engine while the vehicle is in Park, or pushing 'the pedal to the metal' before the engine has warmed up. Help sustain your engine’s performance and efficiency by staying miles away from these bad driving practices.

Can I put water in my GMC C3500 radiator?

Only in emergencies. A 50/50 mix of coolant and water (or a pre-mixed) coolant is recommended. However, if you must keep driving when you're out of coolant, it's better to drive with water in your coolant reservoir than nothing.

Why did my C3500 engine suddenly stop?

There are different reasons your C3500 vehicle engine could suddenly stop. You may be looking at a lack of fuel, faulty sensors, issues with the ignition system, engine overheating, electrical problems, or mechanical troubles.

Who fixes GMC C3500 engines?

For GMC C3500 engine repair, trust your local Firestone Complete Auto Care. You can make an appointment today at any of our thousands of locations across the U.S.

Engine Repairs for Your 1991 GMC C3500

Learn about

1991 GMC C3500 Trim Options

Select your GMC C3500 trim level to learn more about GMC-recommended engine repair. Use the following chart to find information.

V8/5.7L

V8/6.2L

V8/7.4L

Repairs for Your 1991 GMC C3500

Nothing lasts forever. Even your GMC C3500’s engine parts and components will change. We’re here to help when something stops working. Click on a repair below to learn more about 1991 GMC C3500 repairs.

We’re Trained to Care for GMC C3500 Engines

The GMC C3500 is respected for its reliability. You probably thought about that when you got it. However, even your trustworthy engine is subject to wear and tear. Sometimes plans go sideways. If they do, you’ll have to find a dependable 1991 GMC service center — quick! That's when it's time to head to Firestone Complete Auto Care. We've serviced more than 500 million vehicles since 1926, and our technicians know GMC C3500 engines. Schedule a courtesy inspection at the first sign of engine trouble. Firestone Complete Auto Care offers both trustworthy and affordable engine repairs.

My 1991 GMC C3500 Check Engine Light Is On

As soon as your C3500 check engine light turns on, it’s time to get an expert’s opinion. A steady or flashing check engine light could signal a serious issue with your or emission system, and it won’t go away by ignoring it. Potential causes may include a faulty oxygen sensor, damaged spark plug, a clogged catalytic converter, or a leak in the engine vacuum, but that's only a few of the possible causes. Bring your C3500 to Firestone Complete Auto Care to get computerized diagnostics and we’ll figure out why that check engine light is giving you grief. engine rattling, burning smells, or engine misfiring.

1991 C3500 Engine Services

If your 1991 GMC C3500 needs engine repair, our expert techs will let you know what needs to be done and why before they get started. We don't start working until we have your approval. If a service can wait, we’ll make sure you know. But if immediate repairs are necessary for your safety, we’ll make sure that's clear, too. We want to provide you with the information you need to make an informed engine repair decision. By choosing Firestone Complete Auto Care for C3500 engine repairs and you can feel confident knowing that we use GMC-approved parts and components like the timing chain or belt, motor oil seal, ignition coil, or another part.

Questions About 1991 GMC C3500 Engines

Why does my C3500’s check engine light come on when I start it? It's okay if your check engine light comes on when you first start your vehicle. This is just your C3500 testing its circuits. The light should go off shortly. Bring your vehicle in if it doesn't.
Are GMC C3500 engine noises bad? Unusual noises can signal a problem with your GMC C3500 engine. Tapping or knocking could mean you need an oil change. A high-pitched whistle could signal an intake leak or misaligned belt. Squealing may be caused by a loose fan belt, and grinding might be coming from the brakes, not the engine.
What could damage my GMC C3500 engine? Certain driving habits can hurt your engine. These habits include driving on an empty fuel tank, revving your engine while the vehicle is in Park, or pushing 'the pedal to the metal' before the engine has warmed up. Help sustain your engine’s performance and efficiency by staying miles away from these bad driving practices.
Can I put water in my GMC C3500 radiator? Only in emergencies. A 50/50 mix of coolant and water (or a pre-mixed) coolant is recommended. However, if you must keep driving when you're out of coolant, it's better to drive with water in your coolant reservoir than nothing.
Why did my C3500 engine suddenly stop? There are different reasons your C3500 vehicle engine could suddenly stop. You may be looking at a lack of fuel, faulty sensors, issues with the ignition system, engine overheating, electrical problems, or mechanical troubles.
Who fixes GMC C3500 engines? For GMC C3500 engine repair, trust your local Firestone Complete Auto Care. You can make an appointment today at any of our thousands of locations across the U.S.