Skip the auto shop - Our mechanics make house calls

How Engine Timing Works

engine timing

Your car engine consists of a number of rapidly moving parts, including a crankshaft, camshaft, pistons, engine valves, rods and pulleys. As the piston moves up and down, the valves move correspondingly, in and out. The crankshaft spins, and the connecting rods pull and push. All of this has to work in perfect harmony.

Different types of timing

There are two kinds of timing, cam timing and ignition timing. The cam timing regulates the valves and pistons, and the whole process is controlled by the timing chain or belt. If the motor timing is off, damage can occur. In some engines, called “interference engines,” the consequences can be especially bad. With this type of engine, the engine valves and pistons actually occupy the same space in the cylinder, but at different times. Since the intervals between the time when the piston owns the space, and the time when the valve owns the space can be less than a second, you can probably imagine the consequences if the timing is off. You could end up having to have your engine rebuilt, or even replaced.

If your cam timing is off, chances are you’ll know because your car will not be running well, if it’s running at all. Your ignition timing, on the other hand, can be harder to identify, but it’s easy to adjust. Ignition timing has to do with the four cycles of your car’s engine. The four cycles are:

  • Air gets sucked in by means of the intake valve, while the injectors deliver fuel.
  • The fuel mixture is compressed.
  • The spark plug fires the fuel mixture, pushing the piston down.
  • The exhaust valve opens to let out the burnt fuel gases (the exhaust).

The most important thing is that the spark happens on time. If it doesn’t, you can end up with choppy idle, no power, or an engine that just won’t work.

You should never ignore engine timing problems, since if the timing is off, serious engine problems can be the result. If your car displays any of the symptoms of bad motor timing, consult a professional mechanic.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
How to Get a Louisiana Driver's Permit
s licensing program. The first step in this program is to obtain...


Related questions

Q: Misfires 3 cylinders stalls

Hello there, thank you for asking about your BMW 760Li. I don't know what year your BMW is, but there was a technical service bulletin (TSB) on some models regarding the fuel injectors. Although I can't seem to locate the...

Q: Whining noise when accelerate and then let go of pedal

The whining is in the CVT transmission and depending on the noise, it may be a normal noise from the transmission. The noise is the transmission CVT belt changing pitch as you drive faster. Sometime the noise will get...

Q: Car won't start after sitting for a year.

If a vehicle has not been started for a year, then you may have a failed fuel pump and the fuel inside the tank may be degraded and can cause problems like a clogged fuel injector. The recommendation I would...