2003 Mitsubishi Galant Code P0300

jacobpaulsen · 2022-09-15T17:19:18+00:00

I messed with the ignition coils now car starts then shakes. Then when put in drive moves 50 feet then shuts off.

STRAILER

✓Experienced Mechanic
55,051 POSTS

Yep, this is a random engine misfire code, which can be one of two things, either you have a weal fuel pump or the MAF sensor is going out. Let's start with the fuel pressure which you get rent a gauge for at the auto parts store. This guide can help you see how to do the job with diagrams below to help as well:

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Fuel pressure

ITEMS .................... STANDARD VALUE

Vacuum hose disconnected .................... 330 - 350 kPa (47 - 50 psi) at curb idle
Vacuum hose connected .................... Approximately 270 kPa (38 psi) at curb idle

Check out the images (below). Please let us know what you find.

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Sep 16, 2022 at 4:08 AM

JACOBPAULSEN

MEMBER
64 POSTS

The car worked fine until I pulled the ignition coils out and put them back in. So, you don't think that the code has anything to do with that.

Sep 16, 2022 at 5:55 AM

JACOBPAULSEN

MEMBER
64 POSTS

Also, the car runs super rich.

Sep 17, 2022 at 3:07 AM

STRAILER

✓Experienced Mechanic
55,051 POSTS

Yes, it could take apart the coils again and looks for bad connections. Also, if you can upload a short video of how the engine runs, I can tell you what's going on. Try to unplug the MAF sensor to see if it changes.

Sep 19, 2022 at 8:31 AM

JACOBPAULSEN

MEMBER
64 POSTS

i got it btw.

Nov 7, 2022 at 3:51 AM

STRAILER

✓Experienced Mechanic
55,051 POSTS

Nice work. Can I ask what the problem was?

Nov 8, 2022 at 2:04 AM

Code p0300?