Why is my check engine light on but my car is running fine?

These problems can range from faults within the electrical system, the engine, fluid levels or to problems within the car’s emissions system. The problem can even be as simple as forgetting to tighten your gas cap – in fact, this is the most common reason why check engine lights appear in the first place.

Are AutoZone diagnostics accurate?

Autozone’s free diagnostic check is not extremely reliable. What they refer to as a “diagnostic check” is just having a code scanner hooked up to the vehicle’s computer. The scanner reads through and finds out what error codes the computer system has registered.

What are the common problems with small engines?

Rough idle, reduced power, poor fuel consumption, excessive vibration, possible change in emissions (heavy exhaust), loss of power, continual backfiring (pop), continual misfiring (sputter). SOLUTION For most of us, we’ve just stepped into “technician” territory. Diagnosing the problem is just the first step.

When does a boat run fine then loses power?

Last year at the end of the season the boat started running bad after running it for about 30 min. I could shut the boat off and let it sit for 5 min and it would run again fine for about 5 min. then it would lose power again and would backfire when I tried opening the throttle.

Why does my car run when the engine is not on?

If the battery is not grounded to the frame, the car WILL run, but will have issues starting and tends to cause some lights to come on even though those are not real problems. (Such as air bag light, and gas light with full tank, etc.) Plus, if you have electric locks and windows, they may have some glitches.

What kind of car has trouble starting when the engine is cold?

My car runs fine, but has trouble starting when engine is cold. My car takes between 3 and 10 seconds to turn over when you try to start it. Once it starts, it runs perfectly. The car is a 2008 Nissan Versa with 120,000 miles on it. The alternator, battery and starter have all been checked twice and are perfectly fine.

What should I do if I have an engine problem?

Below is a chart of common Engine problems and some easy troubleshooting to fix the problem you may be experiencing. This chart is to be used as a guideline for troubleshooting engine problems. For specific engine tuning or recommendations consult your owner’s manual. Battery lead connections are loose. Battery charge low or discharged.

Can a weak ignition system cause an engine to misfire?

For an engine to start and run properly, the energy must arc the plug and keep that arc going until all of the combustible mixture is consumed. Anything less and the engine will be weak, run rough, stall, and misfire. Weak ignition is often confused with a fuel problem since the two systems are codependent.

What causes a small engine to run out of fuel?

Spark plug loose. Low or no compression. Spark plug gap incorrect. Engine not properly warmed up. Running out of fuel. Low idle set too low (Below 1000 RPM). Low idle fuel setting too lean. Electric clutch dragging. Parasitic load on PTO shafts. Crankshaft end play zeroed drive. Water contaminated fuel. Running out of fuel.