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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.
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.
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.
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.
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.
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.
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.