Tailpipe Emission Gas Training
Select from the list below
Screen Shots (Click to enlarge):
• 1: This is a graph of a Chevy 7.4 with a hard hot restart. Note the yellow trace hits 5098 PPM. This shows that too much fuel has entered the combustion process. Note the purple Lambda trace is .8694 showing this is a fuel injection problem. Two injectors were leaking fuel.
• 3: This Cadillac had three shorted injectors. Each rise in the graph shows when a cylinder was killed. Note the yellow HC trace. There are three humps that are lower that the others. These are the cylinders with the bad injectors.
• 5: This vehicle had a no start condition. The yellow HC trace hit 228.4 PPM. The red CO trace hit .02372%. The purple Lambda trace hit 23.74. This engine had no fuel or spark.
• 7: This sample was taken at crank. Note the yellow HC hit 30080 PPM, the red CO hit .02844%, and the purple Lambda hit .7625. This shows there was no spark. When this coil was tested it was good. The spark plugs were removed and were wet with coolant.
• 2: This is a graph of a Chevy 7.4 with two new injectors. Note the yellow trace hits 646.1 PPM. Note the purple Lambda hits 1.1.
• 4: This vehicle had a no start. Before the hood was opened a gas sample was taken. Note the red CO trace only hit .01863%. This shows there was a lack of fuel present during combustion. The fuel pressure was then taken and the reading was only 5 PSI. The fuel pump was no good.
• 6: This gas sample was taken when the engine was cranking. Note the yellow HC hit 23640 PPM, the red CO hit .4441%, and the purple Lambda hit .8237. This vehicle was flooded.