Doggy Daddy
"Junior Member"?? OUCH!!
If you watch the Oil Temp PID get it at least to about 180*F (better still make it 200*) so that it won't cool off during the test. You can run the engine at a fast idle (2000 RPM should do it) to warm the oil.
To get the most from the test observe how the engine reacts to each cylinder being cancelled. On the OBS trucks you can feel the cylinders being cancelled just like the old days with a gasser when each plug wire is pulled. If there is a weak cylinder you can feel it making less difference in the way the truck shakes. The test is pretty generous about how bad a cylinder is misfiring before it sets a code (meaning it has to be pretty bad or the test will result in "System Passed").
Get the truck into OD/Lockup at about 45 MPH (RPM should be about 1400-1500) and gently roll the accelerator on and see if you feel a rythmic vibration that increases with moderate load (not so much that it kicks down) but goes away when the accelerator is lifted to cruise condition or slight decel. That will tell you if it is misfiring all the time or just at idle.
To get the most from the test observe how the engine reacts to each cylinder being cancelled. On the OBS trucks you can feel the cylinders being cancelled just like the old days with a gasser when each plug wire is pulled. If there is a weak cylinder you can feel it making less difference in the way the truck shakes. The test is pretty generous about how bad a cylinder is misfiring before it sets a code (meaning it has to be pretty bad or the test will result in "System Passed").
Get the truck into OD/Lockup at about 45 MPH (RPM should be about 1400-1500) and gently roll the accelerator on and see if you feel a rythmic vibration that increases with moderate load (not so much that it kicks down) but goes away when the accelerator is lifted to cruise condition or slight decel. That will tell you if it is misfiring all the time or just at idle.
