Exam 48: Diagnosing Engine Performance Problems

Sometimes an engine starts and runs but one cylinder has a dead misfire.

What three events should occur in order for an engine to start running properly?

Which of the following is the LEAST-Likely cause of a compression leak?

A collapsed laminated (two-layer) exhaust pipe will often cause a stripe of discoloration on the outside of the pipe at the point of restriction.

All of the following statements are true EXCEPT:

The spark created by the ignition system must be delivered to the correct spark plug at a specified point after top dead center (TDC).

Above idle speed, symptoms of a leaking manifold diminish but still show up on the vacuum gauge.

A(n) ____________________ is a popular machine used to locate vacuum, oil, cooling, and exhaust leaks.

A gummy deposit buildup behind the throttle plate can be caused by poor quality fuel, blowby, and exhaust gas recirculation (EGR) gases.

The item that can MOST-Likely cause an engine to have increased compression, which can cause fuel to detonate in the cylinder is:

Running compression should MOST-Likely be about:

All of the following statements are true EXCEPT:

A traditional ____________________ test measures how well a cylinder is sealed by the cylinder head gasket, piston rings, and valves.

Sometimes, a V-type engine can have a vacuum leak between the underside of the intake manifold and the crankcase. Describe one way to test for this.

The ____ can pinpoint causes of combustion chamber leakage.

Which of the following is LEAST-Likely an advantage of a leakage test over a compression test?

A fast way of locating a weak cylinder is with a cylinder power balance test. Then a ____________________ or leakage test can be performed to further pinpoint the cause of the problem.

How would you perform a wet compression test?

Low compression can result from engine breathing problems and ____________________.

How would you test for a restricted exhaust?