Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1991 Suzuki Samurai JSFACTORY OEM SERVICE PROCEDURE
Fails Emission Test
- Check for clogged air filter.
- Check for engine not at normal operating temperature.
- Check for fuel leakage from injectors.
- Check for fuel pressure out of specification.
- Check for faulty coolant (water) temperature sensor.
- Check for faulty air temperature sensor (if equipped).
- Check for faulty ECM.
- Check for faulty EGR system (if equipped).
- Check for improper ignition timing.
- Check for lead contamination in catalytic converter.
- Check for malfunctioning ignition system.
- Check for misrouted vacuum hoses.
- Check for poor compression.
- Check for vacuum leaks.
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
Comes to youSame-day available12-month warranty
Get a Free QuoteNo obligation. See pricing before you book.