Wolfguy03

Hello folks. Have a 02 MDX that I have been having problems with. Boggs/hesitate bad when driving. Goes away. Sometimes CEL comes on, others it does not. Codes show "multiple cylinder misfire (2,3,4,5,6) and "random cylinder misfire". Mechanic resets codes and car runs fine for them. Get car back in my hands and boom--misfiring again. Mechanic (3 now) must think I'm nuts but I don't know what to do. Plugs aren't old, correct ones as well. Swapped out coils 4/5 a few months back as that was the issue then. Mechanic says egr, o2 sensors are good and no leaks. Any ideas? It's freakishly scary to have the car bog like that especially on the highway. Thank you

Legend2TL

First thought that comes to mind is a electrical wire/connector/harness problem. Perhaps a bad ground somewhere on the engine harness or ECU harness, Could be something as simple as some copper oxide (blue stuff) that gets on brass connectors occasionally (like the battery terminals or ground lug on a wire harness. If it is that they are extremely hard to track down, one suggestion is to go throughout the engine bay and disconnect and reconnect the electrical connectors (look for any oxide or damage to the pins and sockets in the connectors). That sometimes can clear out a bad or intermitten connection. There's also some electrical connection spray (available at auto-part stores or Walmart) that can clear and lubricate the connectors as well. Good luck!

gnuts

iTrader: (1)

I would start by replacing the rest of the coil packs. Those symptoms seem like a bad coil.

JoJoB3

Also remember to check your EGR system (from the top down to the EGR valve), consider also replacing the PCV.. 01 and 02's it was common for this egr system to clog and bring on the multiple misfire code (also at times accompanied with VTM-4 light). to do a regular EGR system check and cleaning.