How do I setup HP Scan to diagnose a low rpm, high load misfire?

[Lil'John]

I've got the HP Pro interface and I'm wondering what items I should setup to help diagnose a low rpm, high load misfire. The engine is a LQ4 out of a 2004 Silverado that was swapped into a 71 Land Cruiser. It originally had a 4l80e but I swapped it out for an NV4500 with a custom tune created for it.

The misfire doesn't always happen at low rpm with heavy pedal but often enough. I've tried different grades of gas with no luck.

I've got a few suspicions but I want to be able to narrow it down before throwing money at the wrong place. It could be a loose spark plug, a bad wire, a leaky header, or even a bad tune.

So what datapoints are going to help me most?

Thanks in advance for any help.

[wreckwriter]

There are parameters, at least on my car, available for misfires on each individual cylinder. I would start the and maybe change plug and/or wire on offending cylinder(s)

[sarg]

John I had a similar issue that drove me nuts once. Turned out a coil pack was only getting 1/2 charge so it would only appear in high load situations or when boost went over a certain amount. If you can isolate a cylinder as the culptit, maybe try swapping around coil packs and see if it follows.

[gagliano7]

Check your temp with a temp gun at each exhaust port.If one is off by alot that is your bad cylinder. That is how i found a bad coil.

[Lil'John]

Thanks for the hints so far... I may break down and get a temp gun.

There are parameters, at least on my car, available for misfires on each individual cylinder. I would start the and maybe change plug and/or wire on offending cylinder(s)

Where would I find the parameter for measuring individual cylinder misfire? I tried looking through the list and didn't see it jumping out at me(maybe buried further in somewhere)

[5_Liter_Eater]

PID list, engine diagnostics, misfires. Add all current and history.