Q: P0300 code, misfiring on a '06 Hmamer H3

asked by on

06 Hammer H3, 87,000 miles, inline 5 engine. Got the P0300, multiple misifres. I've changed the sparkplug, coil pack, VVT solenoid, cleaned the throttle body and MAF. I don't know what else to do. Any ideas?

Those things are notorious for having fuel injection problems. GM made them with cheap plastic and the fuel injection parts, so when they get to be older, after 10 years old, the plastic cracks, leaks, and gets multiple misfires. That’s a typical problem with that.

It can be hard to diagnose the P0300 code yourself. It can easily be the injection system and that is a very complex system. You don’t want to take the whole engine apart yourself, which you’d have to do to get to the injection system. My recommendation would be to have a professional technician, diagnose Check Engine Light for you and make the necessary repairs.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. P0300 code, misfiring on a '06 Hmamer H3

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: i need a alternator

Hello, thank you for writing in. You are correct in thinking that your charging system has failed. This is very likely the situation at hand. With that being said, you should still have your battery tested. Typically this is a...

Q: Q: Engine sludge?

If you have excessive sludge in the engine, then the oil that you pour into the engine may not be able to drain down into the oil pan. You should change the oil and filter using 6 quarts of 0w30...

Q: I have a jerking ticking and popping noise when I accelerate what is it

Would need more information on the car and engine you have but the problem sounds like a misfire from the ignition system or carburetor problems.

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...