Engine Misfire code 2000 4runner

[Wasatch Rebel]

Hi. I have been having a problem with a check engine light manifesting as code P0300 through P0305. My mechanic was unable to detect any misfires, but after several months of this, my runner needed to be inspected according to state of Utah law and it failed because the CEL was on. The codes read the same so I took it to the mechanic again and they decided that it was one or more of the fuel injectors, so I had them replace all of them. They also replaced the intake manifold gasket. The CEL was off for a couple of days but is now back on. I need to get this solved in order to get it to pass inspection and legally drive it--even though from all appearances, there's nothing wrong with the vehicle. Any help would be appreciated.

 

[aontkos]

Hi. I have been having a problem with a check engine light manifesting as code P0300 through P0305. My mechanic was unable to detect any misfires, but after several months of this, my runner needed to be inspected according to state of Utah law and it failed because the CEL was on. The codes read the same so I took it to the mechanic again and they decided that it was one or more of the fuel injectors, so I had them replace all of them. They also replaced the intake manifold gasket. The CEL was off for a couple of days but is now back on. I need to get this solved in order to get it to pass inspection and legally drive it--even though from all appearances, there's nothing wrong with the vehicle. Any help would be appreciated.

Well, after a quick Google search, a P0300 is a misfire code that is not cylinder specific. P0305 is a misfire in cylinder #5. You said that the CEL is back on, so go have the code read and see what it says.

If you replaced EVERY injector and your plugs/wires are good, then I'd put money on a bad coil. It could be as simple as a bad connection between the coil boot and the plug. Easy fix.

 

[octanejunkie]

A new coil fixed the same issue for me about a year ago

 

[Wasatch Rebel]

Well, after a quick Google search, a P0300 is a misfire code that is not cylinder specific. P0305 is a misfire in cylinder #5. You said that the CEL is back on, so go have the code read and see what it says.

If you replaced EVERY injector and your plugs/wires are good, then I'd put money on a bad coil. It could be as simple as a bad connection between the coil boot and the plug. Easy fix.

I'll give that a try next. Thanks!

 

[kolelt]

Try swapping #5 with a different coil. Clear the code and see if it reappears on the other cylinder. If so it's a bad coil pack.

 

[Wasatch Rebel]

Try swapping #5 with a different coil. Clear the code and see if it reappears on the other cylinder. If so it's a bad coil pack.

Thanks. I assume the coil packs are all the same, correct?