1996 Infiniti Q45 Showing a mis-fire on cylinder 7

[Skibane]

Quote »PO15 Engine Collant Temp Circuit Malfunction (Not sure what that is)[/quote]It means the engine computer isn't getting a valid signal from the engine coolant temperature sensor - and thus doesn't have any idea what the engine temperature is!

It can make your engine run like crap - and needs to be fixed. Check for a loose connector on the coolant temperature sensor - perhaps you disturbed it while swapping plugs or coil packs?

[maxnix]

When you change both plug and soil pack, you lose a degree of control so will have to perorm one more switch to isolate. At least you didn't change the injector also!

Read the article on ohming the injectors.