Thread: Flashing check engine light (beginner)

Hey guys!! Sorry it's been so long since I've last replied, I've been extremely busy, and a little disheartened after I did all of that work and nothing came of it . I finally found some time to take my grand prix over to autozone to not only get the scan done but actually have the receipt printed out for me!

Slowna06 I will definitely try those things you've said, thanks for all that information.

Here is what they printed out for me.

Troubleshooting: p0300

Oem Brand: Domestic

Definition: Cylinder misfire detected.-random cylinders

Explanation:

The powertrain control module monitors the crankshaft speed and has detected a misfire condition.

Probable cause

1. Ignition system fault-spark plugs ignition wires, coil (I've changed all of those!)

2. Vacuum leak

3. Injector fault

4. High or low fuel pressure.

Thank you all for your help so far! I'm hoping I can get more so that I can understand what this all means and what to do next. I'm kind of excited and re motivated to work on the car and get it fixed so I can finally drive my baby again.

Oh and the guy at autozone told me to spray brake cleaner (or fluid? can't remember) on the vacuum hose while the engine was running, and if the car died, than the problem is the vacuum leak. Does this sound right to you?

First double check that all the plugwires are pused all the way on the plugs, and that they are all going to the right cylinder. Not questioning your abilities, but its best to start with the easy stuff. Also check all your wiring to make sure it is not rubbed through anywhere.

Brake Cleaner - It will change the idle, might cause it to rev up instead of dieing down. Also spray around the intake to check for a leak there. Avoide plugwires, coils, and exhaust manifolds- we dont want a fire.

P0300 - More then likely if it was an injector(or coil) this code would have a buddy code- saying what clylinder(s) have the misfire

Low fuel pressure can cause this code - hard to test without a gage.

A crank position sensor can cause this issue when it starts going bad - common problem on these engins

Also an ignition control module(the thing the coil packs sit on) can cause this code.

Originally Posted by Brian99SE

Xander, Im in Kentucky. Im a few hours away But I could help, Im over in Cadiz... Just West of hopkinsville.

Hi, I appreciate the offer, but I might have figured it out! Not sure yet though so I'm going to test my theories here. If it turns out I'm wrong I'll definitely take advantage of your gracious offer.

I remembered last week that this problem started after my car was low on gas, so naturally I went to fill it up. I never read the owners manual so I never read about how you should use premium gas with this car. I had been using regular gas for over a month. Today I figured what the heck might as well buy some stp fuel cleaner and carburetor injector cleaner. I used both and at the same time and filled up with premium gas. WOW! It felt like a lot of vitality was restored but it is still slightly rough on acceleration. Not nearly as bad as when the problem first occurred but no where near the smooth instantaneous acceleration as before the problem came up. I miss that version of my car. My oil hasn't been changed in a while, could that be why it's still a little rough on acceleration?

Or have I done so much damage that it will never be restored? Is the problem fixed or is it normal for your car to run like that after these additives are added, even if your car still has problems wrong with it? One other thing I did was park the car and check what rpms it started getting rough at by throttling it ever so slightly and then all the way up to full throttle. It didn't seem too bad (this was after the gas and additives) but it didn't go past 4200 rpms while in park at full throttle. It started chugging a little when it got there and wouldn't go any further (didn't die the meter just wouldn't go further) is that normal?

You guys are awesome, I never thought I would learn so much about cars, and never thought I would find it this interesting!

I understand that I has been almost 2 years since this all went down for you, but do you remember if your car had horrifically bad gas mileage during these issues? I seem to be in a similar situation, and I'm getting about 7 miles per gallon

It's a 2006 with a 3.8L Supercharged, 145k miles. I was planning for a tune up some time after the new year, but this all sprung out of nowhere